93 octane gas question to Tractor Vet and others that know

I just got back from my only known source of 93 octane 100% gas. They have been out for 2 weeks! When I asked the lady that owns the station when they would have some more she said they had stopped making it! This is Sunocco brand{hope I spelled that right} I have no other source for 93 octane real gas that I am aware of. There is a place that sells racing/avation gas about 25 miles away. Can I mix the racing gas and 89 octane real gas and get something that will take care of my tractors? What about octane boosters? It is not my intent to start an argument here. Run what you want in your tractors. I have a gas 560 that saves me when everything else fails and I want to take care of it. I also have a super M that will fire right up after it sits 6 months. The M will run for 5 minutes after you turn it off on any other gas. I learned my lesson in the 70s with a 351 cleveland. If I bought gas from a shady station that sold regular out of its high test pumps I found myself pulling the intake to replace pushrods. It took me twice to learn. I may not learn quick but I want to take care of my tractors. Thanks for any help. Lee

I think you're wasting your time and money. A 560 and older are low compression engines, unlike a 351 cleveland. It's like feeding your dog steak when dogfood is all it needs. If you turn off the gas and let your tractor run till its all burnt when you're shutting down you won't have a problem with "new" gas clogging up your carb.

You need to remember these old tractor where built back when gas was not near what it is today. Many where built back in the war yeas so good gas never made it to the farms it was all the worst a guy could get because the good stuff went to fight the war. I have too many tractor and they all run on the cheap gas. Ya if left sitting a long time it can and will evaporate but the old gas did that also. So in other words your wasting your $$. Now ya if you where running it in a lawn mower with plastic parts you need non-alcohol gas

Both of your tractors should run just fine on the 89 octane. If you are working those tractors to full capacity every time they are started up, then you need the 93 octane.

I run the E10 in my old Farmalls. They have sat up to one full year, and still started right up and ran perfect.

Read your manual. 93 octane was the rating suggested when the tractor was new and octane was measured using the Research Octane Number(RON). Todays fuels are rated using the AVERAGE of the Research Octane Number (RON) and the Motor Octane Number (MON) which usually arrives at it's octane number 8 to 12 octane lower than RON. If you have 93 RON + 81 MON the average is 87 octane - and it will say it on the pump (R+M)/2 and refer to it as the "anti knock index". We ran a gas 656 over 20k hours on 87 pump fuel with no fuel issues and have run every other gas tractor on our farm with the same fuel 87 octane with no issue. If you have issues with knock while using 87 octane you might have a carb or timing problem - but its not your fuel.

im kinda lost on the part about pulling the intake to replace pushrods.

And your M was lucky to 81 octane RON when it was new. You can't even buy fuel with that low of octane today (that I know of).

The only source would be a custom blend of Av-gas at a local airport or some Marinas carry a custom blend for high HP boats.
Either would be very expensive.
Phillips / Conoco is the only one I have seen that "allegedly" has no ethanol. I believe if you start researching the subject, you will find most fuel companies are producing all "advertised" octane levels to include a percentage of ethanol. Here in Texas it is no longer a requirement for stations to identify fuels containing ethanol. Even though most still have the "10%" stickers from before.
You might ne able to find the highest octane gas, but I would bet it will still contain ethanol.

I lived in Knoxville going to the University of Tn at the time. I lived out Alcoa highway and generally to pull onto the road you had to accelerate pretty quickly. When you did this with regular gas sometimes you would bend a pushrod. To change a pushrod on that engine if I remember corectly I had to pull the intake. If that isnt correct I must have had to replace a lifter too. Anyway I had to pull the intake twice over it and I had bought what supposed to be high test. This was in the 70s during some of the gas shortages. I talked to some of the locals and finnaly found out who you could trust when buying gas.

I have eleven restored tractors anywhere from a H all the way to a 1456 . Fuels are Gas, Propane, Diesel.
These are all show tractors With a little farm work.
No matter what octane pump gas I used I always had Carb problems even if I ran them out on shut down.
Understand these engines are all rebuilt with Electronic Ignitions and professional rebuild Carbs.
Three years ago I drained all gas tanks and switched to 100% Aviation-gas, my problems disappeared these tractors can sit a year and are off and running immediately with no smoke, stink, or coughing.
The propane's and diesel I have had no problems.
I purchased a hundred Gallon tank mounted on a pallet and once every other year go to our local small airport and fill up. I understand Av gas has a 10 year shelf life.
Just IMHO,
Tony

Listen to dhermesc's post. HE is correct. The Tractor Vet is almost always correct, but not on this subject! (sorry to disagree) but valve stem coking issues and stuck valves are related to the lack of stem seals, not fuel. Ethanol fuel has not been an issue unless it is a first time use in a system that is fowled by residue from evaporated (probably leaded) varnish. Jim

Bent push rods is never likely to be caused by a gas problem. Sticking valves or timing being way off yes. That is why back then many companies recommended an upper lube be used from time to time

(quoted from post at 13:15:29 01/09/16) . . . generally to pull onto the road you had to accelerate pretty quickly. When you did this with regular gas sometimes you would bend a pushrod. . . .

Click to expand...

Unless you have sticking valves, bent pushrods are almost always the result of floating the valves by over-reving. In the scenario you describe, I will bet on the over-reving. Rather than chasing down a different brand of gas, you would have done yourself more good by adding a rev limiter.

(quoted from post at 11:45:17 01/09/16) . . . Can I mix the racing gas and 89 octane real gas and get something that will take care of my tractors? What about octane boosters? . . .

Click to expand...

But back to your original questions, sure you can mix regular gas, racing gas and avgas in any proportions you want and the result will be OK in your tractors. Your resulting octane rating will never fall below the lowest grade fuel you mix in. Most products sold as "octane boosters" have little effect on octane rating, may up it a little. Note that most products sold as "lead substitute" are valve lubricant and may actually reduce octane (just like adding motor oil to gasoline).

As far as Octane considerations ONLY theres no need to use higher then 87 octane in old low compression low RPM gas tractor engine. SURE if you have built one up to high compression then you need higher octane gas to prevent pre ignition spark knock. Higher octane was designed and used for HIGH COMPRESSION which most stock old farm tractors certainly DO NOT HAVE.

HOWEVER a person is free to use any gas they like if it makes them feel good. Any person is entitled to their own opinion but NOT to their own facts lol. However if higher octane also has other additives that can help an engine then fine but talking ONLY octane higher is NOT required (to stop pre ignition) unless you HAVE HIGH CIOMPRESSION..........

Remember I'm ONLY talkin about higher octane being required for higher compression NOT other additives or lead or ethanol or anything else or better quality so don't anyone have a calf or take more then what I said...... AND USE WHAT YOU LIKE NOT WHAT ANYONE HERE SAYS LOL

John T

Yep i know we have the same problem here as the best we can get now is 90 Octane . And yep we now not only have one 706 down with a melted piston but two . And some of you guys had best set down and reread you org. factory manual again. And yes they will run on 87 but you can not work them on 87 due to the fact that it BURNS HOTTER and faster then the 93 did. And the 93 rating was THE LOWEST you were SUPPOSE TO RUN . Now take in the fact that hey these tractors are now OLD and have been rebuilt how many times and how many times have the heads been shaved dow to remove warpage and what about the block how many time has that block had the deck milled to flaten them out and the contour bores been recut ?????? did ya ever thing of that and each time you do one or both this raises the compression ratio Then you add in the LACK of a FORGED piston and you now are having major heat problems that qwill happen so fast and NEVER show up on the temp gauge even if it is working because of the time it takes to heat the coolant to show on the gauge . Now as to your 560 yep they did requier 89 octane MINIUM and here again how many times has that head been trued up ?? Now someplace i am sure that there is a spec. on the minium thickness of the head but neither myself , nor my old friend that ran one of the best machine shops with the latest and greatest equipment this side of the Mississippi and even the guy i use now since My long time Buddy Dick W had his heart problems stopped doing machine work. and has now since passed away we have never found that spec. Am i sure that the ing timing is correct on these tractors , yep they are dead on as to Mfg. spec.'s and i am one of those old farts that still know how to run a dist. strobe and set up a dist. Something i have been doing since 1964 . Now as to blending av gas and what ever you can get well i am NOT a Chemical engineer so i am not going there . But i know of a place in Columbus Ohio that we have used back when we first had the problem that probable tell you . At the time all i knew was that we had a problem with the gas when we had the first melt down . They required a sample of the onfarm gas delivered in person in a new clean one gallon container and they would test it and tell us what all was going on . at that time they were also testing gas samples from several Mercadies (sp) dealer that were experiencing engine failures also due to the wrong fuel used in them , guess what they were MELTING pistons also . What they told us was the gas that was delivered to the farm was NOT the 93 octane that was ordered and it was infact 87 and that the gas we took down to them was from Ashland refining ( we never told them whos gas it was they told us) . The head Chemist explained to me as to what was going on with the socalled todays reg. gas and how it reacted on the BURN and what happens at peak combustion with todays gas. In as simple terms as he could explain it to me is that at peak combustion the heat is from the burn is so fast and so super hot that it almost off the scale and with the 93 it was a longer slower burn that makes more power and burn cooler . And you guy probable have never delt with the older cars and trucks of my era . And yes most gas back them had lead it it , all but Ammaco it was lead free back then and yep they had a reg. gas that the Ma and Pa grocery getter ran and it was 95 octane and there hightest was about 107 for the cars with 4 Bbl. carbs and more and big trucks of the day yes i am talking about the BIG gas burners that roamed the roads . First big truck i learned to drive on was B60 Mack with a huge 6 cylinder Mack engine that had a four bbl carb along with a five and four transmission that pulled a fifty ton lowboy that we moved heavy equipment with and yep ya got 3 MPG and it reguiered nothing less then 105 . Every car i have owned all required hightest from back then my 56 Ford with the 292 with the dual 4bbls and isky cam and the Headman headers and the Mallory dual point ing. needed 105 and feed it the same gas as the Mack got from the same fuel stop that cost me a whoppen 14.9 cents A GALLON and on up thru my 71 Duster 340 the last car i have ever owned . Then came the pick ups my 1973 Ford F250 4X4 stayed stock for about 6 thousand miles then the junky 360 was pulled and one of the last Factory 428 S/SJ from the factory racing days was added into it and yep it needed 105+ and Sunoco 250 ran well in it The mid sixtys thru the mid seventys was the hayday for the gassers and by 75 the end was apon us and the gas tractors were gone along with the fuel that they needed . Ammaco was one of the last to hold on to there hightest and the 95 octane reg along with Clark Oil . With the onset of the EPA and unleaded gas MFGer.s were cutting compression and cam timing along with ing timing to meet the reg.'s and so the decline of octane . Now today the modren gas engine has percice fuel delivery electronic ing. anti knock detectors cam sencors this and that where as the not so perfect OLD tractor engine does not have all of this and even if you have the carb totally rebuilt and the dist done deqad nuts on and the timing set as close as humanally posable it is still not getting the job done with this new formular gas . Your car or pick up for the most part is not WORKING hard dragging your donky down the road , but that old tractor is working anywhere from 65% to 100% of it's total capabilitys and it gets HOT FAST , a lot hotter then a diesel does . And so we come to this why can't we get NEW gas tractors today?? one probably because they could NEVEr get the End of prosprous Amercia to approve them due to emissions and who would they sell them to ?? Around here we still have a bunch of WORKING gas tractors on the farms that are not a weekend play toy , the run dow as to working gas tractors just in a two mile square is (20 460's ) (3-400's), (4S/MTA's) (1-450, (6 706 gassers from 1964 thru 1967 ) , (1-1850) about a dozen John deeres ab out a dozen M's and super M's a bunch of Fords and yes we are having problems with them also . Most of the probelms are with the later high RPM engines up past the 400's and 450's witch all were built in the sixtys and up. Then thre is Vernon S/MTA it has been on the same farm since 1955 one of the last S/MTa's sold as his grand father bought it for a couple hundred bucks less then the new 400 and it has had five rebuilds since new , been burnt under a picker once and rebuilt . Now that one may hve to be rebuilt once again due to the fact that with the pistons we used on the last rebuld are now to high of compression for the gas we now get as we used the pistons for above 8500 ft. alt. and a Stock 450 gas head along with a stock 450 gas maifold and Blue printed cam . yes it makes some seirous hp. and will run the New holland Grinder mixer almost as well as my 806 D. does. And better then Eugenes 706 does WHEn it is running . Now keep in mind here guys that i do have a lot more years at building engines then maybe a varyfew have , remember i said BUILDING not just rebuilding . I like working on tractors and making them go , lot easier working on a tractor then working on cars unless your doing something inthe cab of a newer tractor or under it then it is as bad . what turned me off on the car thing was the 67-69 Mustangs with the big blocks and i worked on a buch of them as i was the head performance Mechanic/ Tech what ever the today title is . For a large Ford dealer ship and i also worked on the OLD heavy duty Ford trucks with the BIG old gas burners . So yes i have seen all sorts of problems with gas burnning equipment from 1962 to date . I have come up with some cures on my own and worked with engineers on other . Solved the vapor locking of my 56 Ford on my owne and not with clothes pins or insulation wrap or tin foil , helped solve the same problem on the 68 MoPars with my idea that the factory engineers liked and made a small inprovement and was brought out as a infield fix . I try my best to HELP with your problems as i can with setting here reading what your problems are and SOME of you are as bad as the girl that would bring in her fancy mustang or Toreno and explain her problem . Yep i probably make some of you mad But i am and never will be P/C .

The biggest issue using ethanol for the first time is a dirty fuel system starts to clean up by sending all the "crap" (varnish, gum and sludge) down stream - eventually ending up in the carb and combustion chamber. If it makes it through the carb you're fine - but a lot of times you'll end up with a clogged jet or more.

If you hardly burn a tank of fuel every season you do need to add a fuel stabilizer - wouldn't be a bad idea with "real" gas either. It's not like dirty carbs or water in the gas are something new.

Agreed - you should read your manual and but you should also know what it is telling you.

Here in central Iowa the place where I buy my gas has ethanol blend and two grades of non ethanol. I always buy the cheapest non ethanol grade for my tractors small engines and antique cars. I believe it is 87 octane. I use it in my farmalls john Deere 60 and 51 8n ford. I have not had one bit of trouble, they always start and run great. When winter comes and they sit for several months I add Sea Foam to the gas. One time I had some gas go bad because I let the vehicle sit for four years.

I know what it is telling me and yes i can read even though i went to a little school and i never went to a fancy collage . But i have gone thru a whole bunch of schooling in engine transmission and rear end . both gas and diesel and standard and automatic including Powershift . So here is something for you to think about , Try and run a org built car engine from the time frame of when these tractors were made on what we have for gas today . Will it run yea it will start and run on it so will a briggs and Stratton But stick your hoof into it and tell me what is happening . we are not talking about a 10 to one engine we are talking about Ma and pa's engine at a 9 to 1 or a old plum wore out chebby 235 6 yep you will hear the pre ing rattle or ping as you wish . On the old V8's even the 93 would carry on . and like i said before the 93 was the minium and the 95 was the common for reg. gas. Now if and when you find a expert with the degree in the field that can show me that this stuff will work in the old engines that are working at a constant load of 65% and above and not melt pistons and show me a cure that will work i will stick to my own findings that i see with my two eyes. as i have already gave that Lab enough of my money to see and hear what they have already told me . And oh yes according to the ORG 706 operators manual that i HAD that went with one of the last 706's that i sold it DID state R+M=2 of a min of 93 was to be used . Now as long as i can remember that has been the standard for this area.

An engine with fuel mixed into the air that relies on a spark plug to ignite the flame front makes the best most efficient power when it is on the edge of spark knock. Not rattling like 5 BBs in a Folgers can (before plastic). That difficult timing-fuel-compression triple point is set in today's engines by the use of computers and detonation sensors that continuously "listen" to the combustion process. The computer then memorizes the triple point data so it can predict the curve needed from cold start up to full load summer running. In my opinion and from experience, setting a non computerized old tractor to assure it does not melt pistons, is mandatory. A slow turning engine is more prone to harmful detonation than that same engine running at higher speeds. As the flame front travels from the spark plug to the extremes of the chamber, the pressure and as a result of the pressure, the temperature also rises. If the resulting temperature reaches the ignition temperature of a portion of the fuel air mixture, it will detonate as an explosion rather than burn across its volume. If the engine is turning 2000rpm the travel time of the flame front is rapid enough to capture this portion, resulting in serious knock. That same timing at 3000rpm will not produce knock. If knock is happening (beyond a tiny amount) the timing is too advanced. My experience speaking as well as toyota/Ford/Nissan/IHtruck/Datson/Honda/and an associates degree from Vincennes University. Jim

Well if you did in fact run a 656 gas for 20000 hours then i am 100% sure that it has been overhauled no less then 6 times Now if it only ran 2000 hours and it was new then the gas you had when it was new was NOT 87 octane . And the oil that Came in it was also the LOW ASH . +

I operate (daily) a 1957 Jeep CJ3B with stock engine and stock timing. It never detonates on 87 pump gas. I have a 1951 GMC 3/4 ton stock (original engine 270inch never apart. I can drive it up a hill in 4th from Idle by stomping it to the floor 87 pump gas; it just torques its way up. I was raised driving 216 Chevys in trucks and cars. as well as 292,312, Y block Fords. I wrenched my way through schools and have been a successful service manager. I feel my credibility is reasonable. Jim

And when these newer I H engines are working just where are they working at in the 2000 to 2400 RPM range and even with the ing timing as dead nuts on as humanly posable and the lack of the forged piston they plum Melt down . I have run the dist.s on the strobe and have them dead on as per I H specs at the given RPMs and the total advance set and they will heat and expand so fast it will make your head spin , The first sign is a Miss then a sputter and sometimes a knock and then a seeze up and then a no start due to seezed piston or pistons . Let it cool down and it will start sometimes you will not notice anything for a little while till you pull the dip stick and find that oh my where did the oil go , then other times you will have a knocking . You never hear the pre ing and yes the carbs are done and done correctly . Once we moved up to the 93 Like we Found in the manual we had no problems even under heay load for extended time frames like plowing a 15 to twenty acre field on a warm day . Even running the haybine that is a John Deere 1219 9 Foot cut in first crop will work the snot out of a 706 and at times have a hard time maintaining 540 on the pto on our humps and bumps , Now that they have done away with the straight 93 i do not know what they are pushing that they call 93 but they say that it is 90 with something added to Makle it the 93 well it has eaten two pistons on two differant tractors as todate that i have yet get tore down. . One of these days you and i will have to chat on the phone .

No point in arguing with you is there? Nobody else is the expert you are, and nobody else has done more than you have, have they?

According to the Nebraska test report for the gas version of the 706 it was run on M=84, R=92.8 which equates to today's 88 octane with the (R=M)/2 formula.

I think this is the most I have ever seen Jim Nicholson cranked up.

I do not see any need to run 93 octane unless it is a very high compression engine being worked near the HP limit. The OP who had an issue with run on, probably had his idle speed set too high. The higher octane does help that, but not needed if it was set correctly. I am running 91 octane in my MH44 EFI while I am doing the dyno tuning, and have not heard any pinging at all.

I am curious if the rebuild kits have forged pistons in them.

I have mixed race gas with pump gas with out any problems.

NOPE

I believe perhaps the rebuild kits we have available now contain pistons that were designed & manufactured much differently than the originals. I would like to see a detailed comparison on the vintage pistons ability to dissipate & control heat caused by today's faster burning fuels, compared to the many aluminum replacements we have now.
I worked for Cummins engines for years, and their solution for the use of aluminum pistons was a coolant nozzle for each piston that bathed the bottom of each piston with engine oil.
Many of the old girl's pumps would be turned up ( buttons & shims) BUT you certainly had to keep an eye on your Pyrometer ( exhaust gas temp) during a hard pull, I have seen many melted down. Perhaps a bit of this technology can be adapted to Gas engines using the new aluminum replacements to prevent over- heating & swelling of the piston in the bore using these "modern" cheaper to produce fuels.
Can anyone offer metallurgy studies of modern pistons compared to the originals ?

don't know . Lets just say what i have Learned over the course of time . Now If someone can show me then i will take heed . Am i good well that is what the people that know me personally keep telling me . do i know everything not hardly . I'll let ya know when i do . Now think of this how MANY TIMES have i had to asked how to fix or what could the problem be ?? I think twice on something that i have never run into on a non Red tractor. are there things i have never worked on on a red tractor yep , i don't do hydro's i do not know much about the PFC hyd systems i do not know the transmission of the 88 "s . If i am missing something on the gassers that i may have over looked or never thought about the i am all ears. Do we want to just scrap the gasser we have around here , not hardly . I have said it before if i was a computer wizz and knew how to scan and post the lab report from the place that did the lab work on the gas that caused the first melt down i would gladly show it to you and i do believe even jim would make heads or tails out of it .

Nascar has been working with various configurations of combustion chamber " squish" . This began in the fifties & sixties, designing & implementing piston & matching cylinder head configuration to develop more horsepower on "pump" gas without raising compression ratios. Basically a greater area of flat surface to flat surface area matched in the piston face to combustion chamber ( head) to improve & control the air/fuel mixture at the top of the compression stroke.
Since these were high rev engines compared to Farmalls, I wonder if any such improvements could help control detonation, and heat build up at high outputs on such low rev engines.

Probably. Are you running cold plugs in those that ate pistons? If so I would probably back the timing 3 degrees fro total advance. It might be interesting to put a car distributor on one with centrifugal and vacuum advance. Jim

well at one time had had a lengthy talk with Clevitte tech center an a couple guys when we first had this problem and they told me that one one uses these old tractors anymore for work and that there was no need for the forged pistons and due to the cost of making the Org. piston and time required to do so they went with the fast esy way and that they SHOULD hold up for what they called normal work for a gas tractor today . as far as the oil cooling jets to the bottom of the pistons I H came out with that when they brought out the D361 back in 63 as the D361 had one on each piston When they went to the DT 361 it had two on each piston. All the damage is done above the top ring . The piston dia. a is between .019 to .021 smaller then the skirt on the ones we have installed sofar . The skirt to wall clearance we have been using is .004 skirt to wall , the book calls for .0035to .0045 we have been going middle of the road with .004 . and when one of these does swell they swell at the vary top down to the top ring so they swell .025-.026-7 . Ing timing is correct to the book both stacitCarbs a and centrif. If we did a upgrade from C263 to a C291 then the carb is changed or we find one from a C291 and the dist is changed as there are not the same on timing curve. . why do i make a change , because of not being able to get the correct fit on the sleeves , so we bore the block to take the change over sleeves and then it is more of a one size fits all. I do not care where you by the rebuild kit even if you go to Case I H they are the same piston it is that when you buy from case I H or what ever they are today the ONLY difference is that they stamp the Org. part # on the top of the piston BUT the piston casting #'s are all the same , just the price is different . So do you want to spend 75 bucks a hole more for a stamped part # or save that money and get it from the jobber at a reduced cost. And like i said in another post over the years how much has the compression been raised due to milling of the head and block. Do they warp you beatya , how much varys on the light side .006 and on a bad one i have seen it take .030 to get it cleaned up . If you worked on Cummins then you should know that there heads have a min. thickness to be dressed to , now on these I H gasser heads there has to be one someplace but we have never found it . so over the years god only knows how many times the heade and or block as been done and with each dressing the compression ratio goes up when they were new they were advertised as NEW HIGH compression engines more then the 460-560 and a lot more then the 400-450's Shorter stroke higher RPMs shorter time between the power stroke .

Yep we done played the plug thing The best plug we found that gave the least problems are the C86 A C's ing timing for the C291 is 18 degrees full advance on the C263 it runs 23 Degrees these are set at full rated high ideal or in other word wide open . I am telling ya the only thing that kept them running with no problems was the 93 gas . The big thing i had to learn was the difference between going down the quarter mile to dragging a four bottom plow down a field.The tractor is running at WOT and the gov. is usually working the butterfly in the carb someplace between 3/4 to wide open so the engine is putting out darn near 100% down to 75% of max . Eugenes 706 ate a piston on the haybine on first crop and it was a heavy crop of hay . When it went down and before it put a rod out the block we parked it and put my 806 on the haybine . It was working the 806 . we knew that they had dropped the octane coming down the pipe to the fuel rack as our supplier told us this before hand . It was my buddys choice , well we gambled and lost . Then last fall my other buddy's boy used his 1967 706 with the factory C291 to draga big load of silage back fro and away field with that 706 . These are big wagons with tandem gears and can weigh over 30000 lbs . There are three hills that will even suck the life out of Vernon's 2255 and the 1066 . well on one of those hills Andy pulled the 706 down to hard and she locked up . How he was able to hold the load on the hill i have no idea . He called me as i was packing and i got Aron to drop his wagon and go get him with the 2255 . Ny the time Aron got back there Andy had the 706 running but it now had blow by and had a slight knock on #4 He was not able to break the wagon off the hill with the 706 missing so it was a chain drag up and over to the flat and switch out tractors . The only thing i can think of is the design of the head and or location of the plug along with all the times the heads and blocks were dressed and the cheap pistons along and yes i am going to say the gas.

Don't know ???? but with all the new stuff today and computer programs and if ya had a real geek that knew how to do all of tis and explain it to us OLD GUYs . then anything is posable . IMHOP on these engines I H could have made them a lot better . One they could have used more head bolts and i believe helped or stopped the warppage of the heads and stopped the blowen head gskt. , two they could have used a seven main bearing block. , Three stayed with a longer stroke and a bit bigger bore and had better torque longer engine life . You will not see the high RPM 4 cyl. and 6 cyl. engines last as long as the old H - M- 400-450 I also wonder what they would be like with electronic computer fuel injecton , now here i am deffently out of my class.

To answer your question; yes you can mix 89 octane gasoline with a higher octane gasoline to obtain 93 octane for the mixture. Octane increases by simple proportion....for gasoline that does not contain lead. For example: a 50-50 mixture of 89 octane with 97 octane should yield 93 octane for the mixture.

Note, many race fuels contain ethanol which, you stated you did not want, so be sure to read the label. In addition race fuels can contain lead and aviation fuel typically contains lead. Mixing leaded fuel with a non-leaded fuel results in a higher octane for the mixture than simple proportion would predict. Since the lead sensitivity of various gasolines is unknown to the consumer, the actual mixture octane can not be predicted. However, it will be higher than if non-leaded gasolines are mixed.

BTW - All my Fords run great on any gasoline I put in them...sorry could not resist.

Vet is right on this gas deal. In the 70s I had 69 Cougar convertible with a 351m (pre Windsor). City boys wanted to know how I could get 140 mph out of small block stock 300 hp 2 barrel ford. Dad taught me how to get everything a gasser plow tractor to give and then some, without melting it down, hopefully. Family had 2 656 and 2 706 gassers. We burnt up more exhaust valves than pistons.

To Tractor Vet. We recently tore down a 318 engine from a 1987 Dodge pickup. It had just one piston with scoring & burning above the top ring. Ring was not broken. Engine had a knock when it got warmed up to normal. This is all we found. Crank mikes out good, & none of the bearings show signs of a knock. Cylinders show 3 to 4 thousands wear at the top ring travel. Any ideas?

I know what I'm going to say may sound a little off subject, but the youngins bought a YZ80 2 stroke motorcycle that would scorch a piston every time you held it wide open a little too long,tried every suggestion and supposed fix without any success they got to where when they pulled the head and jug and found it had only stuck the rings they would unstick the rings and go at it again,come to find out the problem was a bad crankcase seal, at high speed it would suck air past it leaning out the fuel mixture causing the lean burn problems which do damage to a piston as described in earlier post, also had 2-250 chevy engines that had developed a knock right after being replaced,dropped the pan and could see a black streak on the inside of the piston skirt,after removal it was evident that the piston was to tight on the wrist pin,carried then back to the machine shop and asked what cause them to tighten up after being run approximately 60 miles or less, he when to the shelf and picked up a box that had a TRW piston in it and sit that piston next to the ones out of a TRW kit box and asked if that answered my question, a blind man could tell the difference,the kit pistons at that time came from Mexico and were a poor sight compared to the true TRW piston ,we decided to remove the pistons from the rods and line hone them to the proper clearance and see what would happen, reinstalled them and they worked fine, I use to run a service truck for a construction company and the shop would put the coldest heat range plugs they could get in a truck or unit engine because they had the mindset that you would burn a hole in a piston if they were to hot,these engines were 331 to 1085 cid,due to the cold plugs fouling out there is no telling how many hundreds I changed to the hottest range I could get my hands own and NEVER seen a burnt piston from them, I don't think that the octane rating is all that is cooking pistons as mentioned in the previous post.

well we talked about this with the fuel supplier . Now here is the real kit in the pants . Lets say we burn around 300-350 gallon of gas a year between the 706 and the john deere A And the difference between the 87 and the 93 WHEN we could get it was up to twenty cents a gallon more then the 87 that came out to some place between 60-80 bucks a year more to run them . The old John deere A could care less what you fed it since the most work it gets is maybe running the rake and it run the elevator when we pick corn and it may pull a few loads of hay IF we make idiot cubes . Now at the time we taked about doing the BLENDING of av gas and 87-90 there is a long way between that .20 cents and the cost of 100LL like about 4.90 a gallon . Now the other kinck in the pants come with we would have to take no less the 250 gallon . He tried to just get us two or three fiftyfive gallon drums . No we do not need C12 VP racing fuel that was for the old M M U and god only knows how much that stuff has gone up. Sorry iam OLd and glad i enjoyed my youth and buying SUNOCO 260 or one click past for no more then 28 or 29 cents a gallon and being able to run 13.5 to one compression ratio on the street . so as to just what we are going to do with these tractors it is still up in the air . Do we go and throw more money into them and have then go down again or do we do like we have been doing to all of vernon's olivers and do a cummins transplant and put them back to work. The olivers are a piece of cake to do the Farmall well not sure i have heard of it being done bt i have never seen one or talked to anyone that has done it.

Could be skirt slap , could be a wrist pin , The 87 was still a carb engine . If one hole was getting lean then it might have been sucking air past the maifold gskt. like i said might . been a long time since i was in a small block Mo par . But i am just about to get reeducated on them as i am going to do a rebuild on the 03 Durango as it now is close to 220000and the transmission has and issue with one of the solenoids ,so pull engine and trans and go thru both and put a new chain in the transfer case and what ever else it needs and run it .

Sounds like you were over revving a straight stick.

Pistons all mike out good. Piston slap would be worse when cold. Pins feel good too. I will be looking at the manifold & gaskets. It was on #3. thanks & good luck on your project.

I'm not a scientist, and even though I've built a few "hot" car motors back in the '70's, I'm not an expert by any means.

The issues brought up seem to me to point to there being three problems: lower octane gas AND aluminum pistons, with the third factor being shaved heads/blocks which up compression. Add in a tendency for rebuilders to go with the "high altitude kit", which boosts HP (and compression), and you have an engine that can be operating well beyond design parameters.

From what I'm seeing here, the 30's, 40's and 50's equipment, as originally built can handle 87 octane without problems. It's the 60's and 70's gassers, when manufacturers were taking existing engines and tweaking them for more and more HP, both higher compression and higher RPM, that the octane HAD to be higher, and it was readily available. Not so much anymore, though there are a few stations in the area now that have a no-ethanol 91 premium, at a very premium price of about $1 above 87.

I've been using just regular 87 octane gas for the 3 gassers on the farm. I've run a 9' haybine behind my '44 H, with no problems at all, even on a late, very thick first cutting. My poor old '51 SA has compression that ranges from 25# to 85#, and it's run IH 46 and JD 24T balers. As far as I can tell, both tractor engines are still original. I had the head off the SA a few years ago to replace a head gasket leaking oil on the distributor side, and it's still a 3" bore, and has flat top pistons. (The block was badly freeze-cracked before I got it, and isn't worth rebuilding.) The H engine looks to have never been apart, or it's been decades since it last was. Makes me wonder if I should just re-ring and re-sleeve if my old iron has forged pistons? Or if wrist pins holes are worn, to have them bushed and bored? Is the problem exacerbated by cheap aluminum pistons? Or are there other issues at play, like intake leaks or timing or fuel flow problems at high RPM's that make a lean mixture?

The low compression and low RPM of my old iron may not ever show a problem with low octane gas. Maybe I've just been lucky so far.

Not wanting to ruffle feathers but if the timing specs were made with the older or high octane fuel, could you just retard the timing a hair to allow a later ignition therefore reducing knock and hopefully piston melting?

Wondering what would be a safe amount of horsepower to run a 706 at without melting it down. I've been thinking about one for a chore/light duty tractor. Probably use it like a 50 hp tractor 90% of the time. Mostly looking at a gas 706 because they are plentiful and reasonably cheap.

I have found this discussion very interesting and it jarred some memories from my childhood. When my grandfather was involved on the farm he was scared to death of diesel engines. He purchased one of the very first 806 Farmalls in the area with a gasoline engine. It was the "big horse" on the farm until the early 1970's, when he purchased a 1965 John Deere 4020 gasoline tractor. Both tractors were used as the big horses until the 806 was traded off in 1976. I do recall the engine on the 806 was problematic. By the time it was traded off, the block had been bored to the limit and in that last re-build, it had gone to a specialty shop where is was balanced and blueprinted (as I recall the story from my dad). I do recall the need to purchase high octane premium gasoline for the 806 and then dad found a Conklin product that was added to the gasoline for the 806. Both tractors were used for plowing and other heavy loads, until the diesel tractors started to show up on the farm in 1976. My question to you is if that 806 had a higher compression ratio engine, necessitating the higher octane fuel, as compared to the 4020? The 4020, as I recall, seemed to hold up better, and was less fussy about the fuel it burned, as compared to the 806. The 4020 is still on the farm today, but obviously not being used for high horsepower work either.

Seems there may be some co-relation with fuel / air mixture at high demand, engine timing, octane ratings, modern piston metallurgy, existing higher compression, all contributing to high combustion chamber temperatures at prolonged full load conditions causing pre-mature failure.

As I understand it, in the USA, pump gasoline octane ratings are Research method (RON) + Motor method (MON) and divide that figure by 2. There isn't a direct correlation for grades of gasoline between the two figures. Heptane has both a MON and RON of 0, and Iso-octane has both a MON and RON of 100. (Methane has a 120 RON and MON.) With gasoline, depending on it's composition, it's RON is generally 8-12 points higher than it's MON. For example, gasoline that is sold as 87 octane may have a RON of about 92 and a MON of about 82. You would have to do your own research or check with your supplier for figures on any specific fuel.

IH had form GSSX-5016, dated Nov./1968, which was a "GUIDE TO LONGER GASOLINE ENGINE LIFE". It is not really a service manual, more like a compiled update bulletin for their gasoline engines, most of which applied to the 6-cylinder gas engines. In it, IH states that the minimum octane for gasoline engines is 93 (RON).

Taken from the guide (underlines are in the guide), it states: "A [u:cf5861e288]common fallacy[/u:cf5861e288] is that High Octane gasolines are [u:cf5861e288]"High Test" or "Hotter" fuels, this could not be further from the facts.[/u:cf5861e288] The volatility or distillation characteristics of premium and regular grades of gasoline are practically identical, both changing slightly with the Season of use to insure easy starting in cold weather and to prevent rapid evaporation in hot weather." "Should fuels below the minimum octane number be used in gasoline engines, a noticeable drop in performance may occur."

Other fuel specifications, along with figures and recommendations for seasonal fuels and lubricants are given. IH Low Ash oil may not have been available when this was printed. Use of a low ash oil was recommended for LPG engines, but no mention of IH Low Ash oil is in the guide.

Also, this guide states that most, if not all spark plug recommendations were changed, lists the "new" chrome oil regulating piston rings for C-221 and C-263 engines, eliminates exhaust valve stem seals for the 6-cyl C-___ gas engines, updates the manifold gaskets and hardware on the same, modifies oil filter bases and updates by-pass valves, and advises not to smack a paper air filter around to clean it. A few other recommendations and part updates are shown.

The guide states: "[u:cf5861e288]It has been conclusively proven that exhaust valve burning and piston scoring are, in most cases, the result of hot spark plugs and/or ignition timing advanced beyond specifications.[/u:cf5861e288]" and that failing to follow IH's recommendations on plugs and timing will void any applicable warranty. Also, as far as voiding any warranty was concerned, "The same is true if carburetor jets are altered, displaced manifold service gasket 69752R1 is used, high altitude pistons and sleeves are installed at altitudes below 4000 feet, and any other local modification is used." It also states "... the distributor advance mechanism is frequently
neglected when the engine is overhauled."

AG

Cousins 656 (was my grandpa's new) has been
errand and auger tractor for 20 years on marathon
89 octane gas with no issues. But no plowing or
other field work either. We didn't even pull grain
wagons with it, everything else on farm had power
brakes. But having run that particular tractor since
being 8 years old (it was outfitted with duals at one
time) I would not attempt to field work it on today's
unleaded gas.

So this proves vet is right. The ih gas engines,
especially those in the 06 series running at higher
rpm were prone to piston scoring and/or burnt
exhaust valves unless every little detail by ih was
followed and then still possible failure. You also
have to consider the times. These tractors were
replacing Ms and Hs and were being sold as high
performance plow tractors. The 5 bottom ih sold
with the 706 pulled the living snot out of it. When
cousin and uncle retired the 706 and 656 in 1978
they bought new 886 diesels and kept the same
plows.

I do not make this stuff up. when i come across something that i can not figure out on my own i go looking for answer from someone older that has done more . Like with the low ash oil Myself and the guy that did my machine work he and i go way back to around 1962 , we did everything we could think of to stop the valve burning with no lock. My one buddy i will call john boy still has the 460 his dad bought brand new in 1959as the main big tractor with a 4 bottom plow The tractor was not two weeks old when it ate the first valve and did it twice more while plowing and each year they had that tractor back at the Solona Supply doing the valves . Well in 64 Everybody around here was either buying a 4020 or and 806 . back then i worked construction . The man that owned the company also had two of the nicest farms around He bought the vary first 806 in the area , yes i got to drive it . The following weekend my uncle bought the first one in this county now this was 1963 Old GF's 806 got a turbo installed when it was three days old , my uncles got one stuffed on the second week while it was raining . Both my uncle and G.F. got new 5 bottom plows and new 18 ft. disc. and duals . That really started the buying arond here . Well i have done two valve jobs on John Boy's 460 till i got him to change and we did four total on Eugene's 706 till we switched to thew low ash oil and a guy from Marion In. was the one that explained the valve proplem to me . He and his brothers use to be and old I H dealer ship and they did everything in house including crank grinding . Now myself i have been using 706 gasser since 1983 . I was broke just got out of the big truck and lost my donkey on the sale just to get rid of it and i bought a Rag 706 gasser with fast hitch and a narrow ft. gave 900 bucks for it and found a old 540 4 bottom for 200 and a rough old 13 foot 370 disc and i bought a cream puff 1240 John Deere plateless planter off a buddy for 650 and rented 110 acres . plus i was just getting started on the tractor repair . Well i never gave much thought to it as to gas or the oil thing and since i was so hi tech i have a 55 gallon drum in the back of my pickup and i ran yep you guessed it hightest in my 78 Ford F250 4X4 because it really was NOT Factory stock as it had a 1971 460 on it that sported a 11 to 1 compression ratio and it was really fussy about what you fed it . So when i would go fill the pick up i would fill the drum with the good stuff and fed the rag the good stuff . Now oil well i was running Castrol 20-50 in the summer and 10-40 for winter and that is what the 706 got . Two qt's a day when working it and a pint a day if it sat. I was a good running tractor for the most part under the plow in our ground pulling 4x16's at 8-10 inches deep in sod i could run 4 th low and in corn ground 1st high .i ran a cold Motor craft plug back then , now don't ask me the plug # i have long forgotten and the distributor that handled them has since changed to Autolites. autolites are ok but i have found that the C86 A C runs better . how many times have you seen me tell people that ing. timing is vary important on these ?? And like i have said i am one of those old Farts that knows how to do a Dist. Been curving dist. since 1964 when i bought my own Sun 505 Dist. strobe machine along with a 1020 Sun scope so i could do my own tuning on my car that i ran on the strip. I do not even set the timing on a H or M with out (1) first checking the dist on the machine to make sure the advance is correct and set to the new spec.'s for gasoline (2) it is set with a light not by ear. when and H or M-300-450 are set correct they sound like they are laboring , yep you can crank them up to smooth them out but do you know how far advanced you are when you THINK you have it set. it would scare you. I try my best to help guys out , but some just can't get a grip and they are so cheap that they think they are saving money by being CHEAP The difference between buying 87 and buying the good stuff if you can find it amounts to around 65-80 buck if you burn what we burn per 706 per year and that ranges between 300 and 350 gallon to make over 100 acres of hay there to four times and plant between 30 to 45 acres of corn. But really i don't care what they do with there tractors as they are the ones who will be back on here complaining my tractor does not run. with me ok so tractor broken we fix it and we go back to work . Or like now do i really want to put 6 kits in it and have it do this all over again, now that is throwing good money after bad. So the 706's are DOWN and until i can come up with a way to solve this problem they will set.

I can not answer you on the 4020 gas engine as i am no expert on them . Like i said again and agin back when these tractors were made most reg gas at the pumps HERE was 95 octane and hightest ranged from 105 on up . Sunoco had the highest with there 260 as there 240 was the same as the rest , they also had one more CLICK on the pump past 260 and that is what i ran in my 61 Ford rag top with a 390 tri power that was built to the hilt and running Jahns 13.5 to 1 pistons and the lateset in Cam tech. a Crowler double roller cam and lifters and rocker arms . Gas started down hill after 1976 slowly as the no lead gas was being forced onto us . But engines started being derated with the onset of the 1972 model year . And kept falling down along with gas mileage I think 1975 was the last year for gas tractor but don't hold me to that one may have been 76 . I know you could get a 766 with a gas engine in it .

I have 6 old tractors that run on the cheapest gas in town. Brought home in plastic 5 gallon jugs. It is 89 octane and I run Champion d21 plugs and never had an issue with starting, carb trouble, with any of them because of carb problems. Now, I have rebuilt the one on my Cub and H because of issues not pertaining to gas. In fact had the 1938 Allis Chalmers B hand cranker out last weekend for the grandkids to ride and she started on the 4th or 5th crank and purred like a kitten. She hadn't been started since September. My H is the work horse around my place and runs on the cheap gas. Now I do add a can of SEAFOAM every other tank just because I feel it is a persnonoal thing a buddy works for seafoam and he gets me samples . I have a M that has been (helped ) high dome pistons and was a former puller and I run the same gas in her and problems. She will pull 3 14"s in 3rd gear on the Cheap gas. Just my 2 cents worth..........................Kenny

(quoted from post at 20:54:45 01/10/16) So the 706's are DOWN and until i can come up with a way to solve this problem[b:5aa08c5346] they will set[/b:5aa08c5346].

Click to expand...

So are you giving up on the gas engines entirely? Would a gas 706 still be ok for light duty? Or should they just be considered a ticking time bomb?

We can still get 93 octane non-oxygenated fuel here, but it costs $0.50 to $0.75 more per gallon than 87 octane with 10% ethanol.

The older tractors , now i am talking 450 and BACk do not have this problem as long as you do not have them really built . 87 -89 great just make sure your ing timing is set correctly , Now if you have done what we did on one S/MTA where we installed the 8500 ft. high Alt. pistons and a 450 gas head ( not the propane one ) and done other things to really push the compression way up there is no problem . The 89 will work fine in the 460-560 tractors UNLESS someone put a 706 kit in a 560 or they swapped out the engine to a later combine engine .

The RON number will be (as described above) maybe 10 points higher than the MON #. They are now expressed as an average of the two. thus a number on the pump of R+M/2 of 87 will end up being about 5 points higher to be expressed in the same terms as the manual and supplements from the original documents. Jim

(quoted from post at 01:05:38 01/11/16) So this proves vet is right.

Click to expand...

I'm abstaining from participating in the great tractor vet debate.


IH, dealers, and farmers all may have tried to get more out of bastardized 6-cyl. gasoline truck engines that were put into agricultural and industrial equipment than they should of.

Many of us have explained that 87 or at most 89 octane pump gas should be adequate to meet and/or exceed IH's requirement of 93 ROM. Check with your fuel supplier to be certain.

Improper fuel and/or lubricants, timing, spark plugs, distributor advance mechanism, or improper function of the correct distributor advance mechanism, and other issues listed in that guide will contribute to or cause engine failure.

These engines also tend to rust and sludge up after decades. Coolant flow can be restricted in areas of the block and contribute to engine failure.

AG

(quoted from post at 17:15:36 01/11/16)

Many of us have explained that 87 or at most 89 octane pump gas should be adequate to meet and/or exceed IH's requirement of 93 ROM. Check with your fuel supplier to be certain.

Click to expand...

I meant 93 RON.

AG

BTDT i have covered all the bases , NOW WHAT ?? you have any ideas ?? i am at a loss . As we can no longer get true 93 and the Al-KI- Hol laced gas they are pedaling is NOT doing the job . Now is it the fact that the Al-Ki-Hol is evaporating out to fast and lowering the octane rating while it sets in the fuel tank that sets up on legs in the sun and heats from the sun or what i myself would love to know. So if you have any ideas please tell me .

Did you just read the same post I read?


---------------------------
The guide states: "It has been conclusively proven that exhaust valve burning and piston scoring are, in most cases, the result of hot spark plugs and/or ignition timing advanced beyond specifications." and that failing to follow IH's recommendations on plugs and timing will void any applicable warranty. Also, as far as voiding any warranty was concerned, "The same is true if carburetor jets are altered, displaced manifold service gasket 69752R1 is used, high altitude pistons and sleeves are installed at altitudes below 4000 feet, and any other local modification is used." It also states "... the distributor advance mechanism is frequently neglected when the engine is overhauled."


----------------------------


I seem to recall pointing that out a while back. But telling an owner he used "cheap gas" is a lot cheaper than having to go back rebuild an engine that wasn't timed correctly after an overhaul.

That tractor went 4000 to 5000 between overhauls using pump fuel. The oil that used in it was Skelly Tagolene from day one to the early 1980s when Skelly went of business. Archer oil was used until the engine was replaced back in 2000. If it had only run 2000 hrs between overhauls both operator and the rebuilder would have had their arses kicked.

till we switched to thew low ash oil and [b:66207883cb]a guy from Marion In.[/b:66207883cb] was the one that explained the valve proplem to me . He and his brothers use to be and old I H dealer ship

Click to expand...

Tractor Vet, The man you mentioned is Bill Kriegbaum, he's still alive and kickin' . The man is one sharp individual and I've learned a lot from him over the years. Bill always has time to share information and is free with his knowledge if you're deserving of it and as would be expected is still eager to learn. Well, except for computerized stuff, he leaves that stuff to us "young fellas" (I'm 60).

Yep on the spark plugs Book Calls for a D15Y crosses over to autolite 3116 , Autolite 375 or the A/C C86 that we have been using . Next ing timing , yep set at FACTORY spec.'s Centrifugal advance here again WORKING as Per MFG spec.'s checked on a distributor machine in the factory spec.'s at givern RPM's . Oil used Case I H 30 weight Low Ash . Cooling systems all cleaned out New cores in rad. NOT and import replacement NEW CORES . Blocks and heads were Hot tanked in the old stuff , the stuff that makes the EPA's hair stand on end . Manifolds taken apart and all the crud down in the heat riser area cleaned out one heat riser replaced and the new butterfly tacked into the correct position , heat riser spring pin replaced and new spring installed as per the book. New style manifold gskt used and face of the intake and exhaust ground to make sure they are all flat and true . 263 carb brought up to 291 Spec.'s . Both cams rebuilt to factory spec.s . Yep the block was dressed at the time of the out of chassis rebuild .007 was trimed off the top . On the first valve job done on that tractor it took around .009 to clean it up So yes that raised up the compression Then when we did the rebuild another cut was make on the head . So again that brought up the compression . No we did not put higher compression pistons in it and the first set came from Case I H at around 176 bucks a hole and they had the I H part # stamped in the top of the dome . It ren fine at the shop under varing loads on the dyno for 8 hours of run time . The oil was changed before it went back to the farm . It ran fine all winter long moving hay bales hauling manure but no feed grinding We ground feed with my S/MTA . When spring came we put it on the plow and i made the final check changed the oil and put the plow on it . It ran fine the first day all day . The second day Eugene filled the tank from the Farm tank , the gas he ran the first day came from the little station down the road from his place . He filled the tank with OH Guess what High test . The fuel supplier did not make it to the farm till late in the afternoon while he was plowing and HE was suppose to bring HIGHTEST . Sunday after Curch Eugene changed cloths and filled the tractor with the gas that was now in the tank. He did not make a round when it seezed up and died . He calls me and tells me what happened . Told him let it cool and get it out of the field and down to the shop After it cooled down it restarted BUT NOW IT is knocking . All six new pistons with less then 40 hours of run time are toast. Called my machinest up and he come down with his ridgid hone and we were able to save the sleeves . The .004 clearence that we built into the engine was now .0045 on all holes so instead of going to Case I H for new pistons and rings i ordered in from one of my jobber supply houses that sell nothing but engine parts at a greatly reduced price . This is when i found out that they all come from the same place as ALL casting # were the same just missing the I H part # stamped on the dome . This is when we took the gas and had it tested at a lab in Columbus Ohio . we DID NOT tell them who's gas it was , they told us . We did not get the gas that Eugene paid for as he paid for premium and got 87 . The fuel supplier Cheated him . This same guy caused a lot of problems with other farmers over the years . He would not drain the hose from one fuel deliver to the next , he would not clean out comparments and put gas in onto of diesel or the other way around . So say you ordered 200 gallons of gas and he dumped 150 gallon of gas in ontop of fifty gallon of diesel or home heating oil and then after filling your tractor it would not start because of fouled plugs. Been down that road more then we want to talk about. Oor you order three hundred gallons of diesel and he dumps 250 gallon of diesel on top of fifty gallon of gas , who is that going to work out for you . So we stopped using him and switched fuel suppliers . Tractor ran great doing everything we needed to do with it Till our fuel supplier hired a NEW driver amd they told him to take a load of GAS out to Eugene's Yep he did he brough 87 , yep the 706 locked up only two pistons this time and the sleeves cleaned up with light honing . They bought that engine job . And again the 706 was running just fine till a year ago , now this has been going on now since 1998 when we did the major out of Chassis . So IF the plugs are correct , the timing issue is correct the oil is correct the carb and manifold is correct and system is good . Guess that leaves only the stuff the pistons are made from NOW and the GAS , NEXT

(quoted from post at 11:30:06 01/11/16) BTDT i have covered all the bases , NOW WHAT ?? you have any ideas ?? i am at a loss . As we can no longer get true 93 and the Al-KI- Hol laced gas they are pedaling is NOT doing the job . Now is it the fact that the Al-Ki-Hol is evaporating out to fast and lowering the octane rating while it sets in the fuel tank that sets up on legs in the sun and heats from the sun or what i myself would love to know. So if you have any ideas please tell me .

Click to expand...

Storage tanks should not be exposed to the sun. This was good practice long before there was ethanol added to gasoline. Gasoline will evaporate at room temperature - much more so when heated by the sun. All my gasoline storage containers are completely sealed to eliminate evaporation. I do not buy gasoline by the 100s of gallons however, I see no reason why a large elevated storage tank can not have a valve installed on the vent to prevent evaporation during storage. I believe if you check with your fuel supplier he/she will indicate you are losing octane as the gasoline evaporates.

As for ethanol evaporating first: the boiling point of ethanol is 173 degrees F. This is well above that of the lighter components of gasoline.

And some how i have lost his phone # over the years.

Well lets see here why do we buy 100's of gallons of fuel // First off the closest gas station is just six miles away , Now we could just drive the tractor to town and fill up everyday then drive 18 miles to the away fields or we could fill lots of five gallon cans and stand with one foot on the frame rail and one on a truck bed spilling gas everywhere or having the wind blowing it everywhere . as for not having a vent tank now that would get interesting . EPA will not allow you to use and inground tank anymore unless you follow all the rules and any inground tank must be removed according to EPA guide lines . Shame on you if you have a inground tank . These tractors are not just weekend play toys they were worked everyday to some degree or the other . Now as far as AL-KY-HOl evaporating slower then gas Here i am not sure on that as i think it is the other way around But not 100% on it I'll have to see . Also why do we BUY over 600 gallon of diesel at a time when we could just run to town and buy it at the pump . Well for one it is a lot easier getting to our tank when we have the dual on and hooked to a piece of equipment 14 foot wide and with the duals on you could not get close enough to the pump for the hose to reach. And the other factor here is how about when the power goes out in town and the whole area and we have to run the generator for say three or four days non stop if the power is down in town guess what you don't get any gas or diesel BUT we can as we have it on hand .That is why we buy 100's of gallons of fuel at a time because we use it when we need it.

Well if you know him and he is close if you would have a chat with him about this . I am at a total loss on where to go next .

I just came across your reply referring to the guide to gasoline engine life. I have that pamphlet also. It was given to us while in Hickory Hills training center in the fall of 1969. About one year later or maybe two, IH put out a lot more information when they went to low ash oil and the rubber perfect circle valve seals on the intake valves and back to the umbrella seal on exhaust valve. (was hard to keep up on seals as they kept changing their minds on both gas and diesel engines). The intake valve guide was changed but you could use old when you machined the guide. They provided a service tool for doing that. I machined a whole lot of guides over them years. Perfect circle, of course, had been using the Teflon lined seal and guide machining tools for years already and I had done a lot of the older tractors using those tools and seals. IH put together a engine upgrading kit, pistons, sleeves, valves, seats , guides, seals, manifold bolts, washers & gaskets and a new distributor. Installed several of those. Made a lot more reliable engine. Original 706 distributor was a 25 degree advance BUT, you were supposed to set the timeing at 22 at full throttle. New dist was 22. Another thing, most every head I pulled, (once I caught on) the valve seats were not tight in head. You could tap them right out. I installed a whole lot of oversize seats. Learned that lesson on in-laws Chevrolet. Local machinist had put in valve seats and that engine burned valves like popsicles. Seats never fell out but you could tap them right out. If that seat does not transfer heat quickly, overheated valve is result. Also, before low ash oil recommendations for gasoline engines, I had a customer torch a valve in a 706, very low hours. Did regular valve job, torched it again shortly. Seat was loose, replaced just that one seat with oversize and it took care of the problem. Easy to test for loose seat. Just a very light tap with tool like screw driver through port and if it moves, you are done. Also, loose seats will often show a slight pitting around the edge of head.

(quoted from post at 19:02:50 01/11/16) Well if you know him and he is close if you would have a chat with him about this . I am at a total loss on where to go next .

Click to expand...

Shoot me an e-mail to [email protected] and I'll send you Bill's contact info.

Thank you for sharing your experience and wisdom with us all, Tractor Vet. Although I spend more time on another "color" forum, I do check in on this forum as well simply because in my assembly of tractors, I do have a 53 Super M, a 49 H, and an 86 Hydro (diesel). I have a few more green tractors, but I do have a genuine fondness of the classic Farmalls from the 1940's and 1950's right up through the 350/450 models. The first tractor I learned to drive was actually a 3010 JD gas tractor and subsequently the 3020 and 4020 gas tractors that are still on the farm. My dad never let me go solo on the 806, but I did spend a lot of time on a 706 gas tractor in my teens and early 20's. One does not learn important information, such as you have shared, unless one is willing to read and even ask questions, thus the reasoning behind my question. Thank you for your honest and candid response to my questioning. I did some looking "on-line" and found there was no huge difference in the compression ratio on the 4020 versus the 806 with those numbers being 7.5 to 1 versus 7.7 to 1 respectively. The other key factor I found was the 806 was a 301 cubic inch engine, while the early 4020 was 340 cubic inches and the later ones (1969 and later) were 362 cubic inches. Both versions provided the same 7.5 to 1 compression ratio. The 4020 was given its power rating at 2200 rpm, while the 806 rating was at 2400 rpm. When both were on the farm in the early to mid 1970's, I remember my dad telling me there was not a nickel's worth of difference in gasoline consumed as they burned about 8 gallons of gasoline per hour pulling 5-16 semi-mounted plows. Back in the day, dad talked about someone from the State who went to farmers to review or audit their farm fuel tickets to try and determine if the subjects of these audits were burning farm gas in their vehicles. I even remember my grandfather mentioning something about it once or twice. They both shared with me the man from the State did not dig very deep or request a whole lot of information from them when he was told they farmed with the 806 gas and 4020 gas tractors! They also had 3 other gas powered tractors at the time before the first diesel tractor showed up in 1976.

I got shut out of my hoy mail account because i never did the pass code thing as i have not ude my E/mail accout much since my friend passed away so i got locked out .Best i have i guess is my face book thing ,

(quoted from post at 19:43:16 01/12/16) I just came across your reply referring to the guide to gasoline engine life. I have that pamphlet also. It was given to us while in Hickory Hills training center in the fall of 1969. About one year later or maybe two, IH put out a lot more information when they went to low ash oil and the rubber perfect circle valve seals on the intake valves and back to the umbrella seal on exhaust valve. (was hard to keep up on seals as they kept changing their minds on both gas and diesel engines). The intake valve guide was changed but you could use old when you machined the guide. They provided a service tool for doing that. I machined a whole lot of guides over them years. Perfect circle, of course, had been using the Teflon lined seal and guide machining tools for years already and I had done a lot of the older tractors using those tools and seals. IH put together a engine upgrading kit, pistons, sleeves, valves, seats , guides, seals, manifold bolts, washers & gaskets and a new distributor. Installed several of those. Made a lot more reliable engine. Original 706 distributor was a 25 degree advance BUT, you were supposed to set the timeing at 22 at full throttle. New dist was 22. Another thing, most every head I pulled, (once I caught on) the valve seats were not tight in head. You could tap them right out. I installed a whole lot of oversize seats. Learned that lesson on in-laws Chevrolet. Local machinist had put in valve seats and that engine burned valves like popsicles. Seats never fell out but you could tap them right out. If that seat does not transfer heat quickly, overheated valve is result. Also, before low ash oil recommendations for gasoline engines, I had a customer torch a valve in a 706, very low hours. Did regular valve job, torched it again shortly. Seat was loose, replaced just that one seat with oversize and it took care of the problem. Easy to test for loose seat. Just a very light tap with tool like screw driver through port and if it moves, you are done. Also, loose seats will often show a slight pitting around the edge of head.

Click to expand...

Alot of good information in that post.

I understand that that "guide" is dated. When taking a look through what literature I have-- a couple of different service manuals, some service bulletins, and parts books, it's not hard to see alot was changed (and change was almost constant). I'm not totally sure how complete or up to date my literature is.

One could not possibly explain all of the updates/improvements/alterations to this series of LPG and gasoline engines or the variations between engines and their various applicaitons here. As far as octane demands, no info I have shows any figure other than using gasoline with a minimum Research Octane Number of 93 . I couldn't find the newest service manual I have, but in 1968, compression ratios are all below 8:1, so there's nothing that I would call "high performance" about these engines when "stock". Some were closing in on 3000 rpm's, though.

In 1961 there was a guide of "acceptable" engine oils published. I'd guess it's about 40 pages. In 1964 they changed the oil change intervals to every 100 hours and filter change intervals to every 200 hours for 706 and 806 gasoline powered tractors. 250 hours on an oil change wasn't cutting it. Later IH came out with their "Low Ash" oil, and it seemed to cure or help minimize some of the issues that plagued these engines.

Service bulletins show that the valves, guides, and valve seals were changed several times. Almost looks like valve train roulette, try to standardize this, update that, see if this helps, and try to keep improving. Stellite parts got used in the LPG engines first, and gasoline engines later on. Some of the valve levers were made incorrectly and had to be reworked. Changes were made to piston design, tolerances, and fitting procedure, rings, rings, and some different rings, valve cover breathers were eliminated during 460/560 production, and alot of other changes and tweaks, some large, some small are in the service bulletins.

Parts books show that some of the internal engine parts or assemblies were updated several times. Some of the C-263 sleeve assembly and ring set part numbers are at -R98 and -R99 today.

Over the lifetime of this series of engines, dozens of different distributors/distributor packages were used from at least 3 manufacturers. Distributors, engine timing, and carburetors appear to be pretty much application-specific. Many of the tractor applications had at least one distributor package and timing spec. change at some point. Carb guts got changed on many applications as time went by. Single venturi packages were offered to stop icing and decreased performance when those issues were encountered with a carb with a double venturi. Fuel shut-off solenoids (when used) went through a couple of changes in rapid fashion.

AG

(quoted from post at 06:13:34 01/14/16)

Parts books show that some of the internal engine parts or assemblies were updated several times. Some of the C-263 sleeve assemblies part numbers are at -R98 and -R99 today.

AG

Click to expand...

Should read sleeve assemblies for some of the C-263 engines are at -R99. Parts book calls a it a sleeve assembly or package, a CIH dealer website calls some a "ring set" and some are up to -R99. I was looking at descriptions and not reference numbers in the picture.

AG

I have a 706 gas. As with any low compression engine it doesn't need the higher octane. My dad was an engineer at the Rock Island Farmall plant from the mid '60's til they closed in '84. I ran this by him and he is in agreement. He has a 560 that was used as a brake in the experimental department, he uses regular pump gas and even ethanol in it.
With all due respect Tractorvet, although the owners manual for the 706 does recommend 93 octane on pages 10 and 12, page 13 tells how much to retard the timing setting for lower octane fuels. For every octane point less than 93 retard the timing 1 degree. In other words if you're running 87 octane fuel, 22 degrees minus 6 degrees = 16 degrees BTDC (fully advanced). done this in plenty of automotive engines with 9-9.5:1 compression over the years without any problems too. The higher octane fuels back in the day had more lead in them for the valves, seats and guides. Fuels today don't even contain any lead as hardened valve seats etc have been the norm since the mid '70's.
Heads that have rebuilt over the years will likely have modern hardened valve seats, etc. and not need the extra additives for the top end. If you think your machine has the original head and the seats haven't been upgraded then you can run a lead substitute additive in the fuel for extra top end lubricant if you like...even then, most of these machines don't see enough use where this is even a big issue.