Re: 93 octane?

Posted by the tractor vet on October 29, 2007 at 07:23:07 from (75.19.120.169):

In Reply to: 93 octane? posted by ggg7lazy77 on October 28, 2007 at 22:48:44:

Now lets get this stright here (1) I never said anything about burning valves with out using 93 octain . The 93 octain is REQUIRED on the later high compression gasser being it a 4 cylinder or a 6 cylinder And that is the lowest RECOMMENED FUEL REQ. for these engine as per the Factory OPERATING MANUAL. WHAT burns the exhaust valves on these tractors the lack of using the low ash oil . The 93 octain gas burns cooler and longer . The 87 burns HOT and fast and can and will cause the tops of the pistons to swell under hard loads and they can and will swell over .020 and can swell way ove that and cause the top of the piston to seeze to the sleeves or just plum melt the piston . Guys i have been down the pike way tomany times , i have first hand knolage as to what happens when ya don't fallow the game plan . Like i said a long time ago setting on my desk is a brand new Case I H piston that came out of a C291 that had around 35 hours on a total overhaul . Every pice of that engine was hand fitted by the book and ran like a swiss watch Till the fuel guy brought the wrong gas and how were we suppose to know that . Well the tractor was filled with gas drive to the field Plow was dropped in the ground and before it got to the other end she lost power and locked up . When i pulled the engine down all 6 holes were scored , all the damage was ABOVE the top ring . The pistons tops swelled over .025 , there was .004 skirt to wall clearance and the ring area of the pistons ranged from .019-.021 smaller then the skirt area . First off the pistons of today ARE NOT FORGED THE ARE CHEEP CAST alum. and can not disapate the heat off the tops as fast as the forged can . Second off when these tractors were new gas of the day plain old reg gas was 95 octain and cheep stuff was 92-93 and the cheep stuff would not run well in a old 6 cylinder chebby. When i saw what had happened in this engine from my years of working on engines i knew something was wrong with the fuel . That is when we started looking for a lab to test the gas well after looking around and many phone calls we found one and had to hand deliver a gallon of gas out of the fuel tank at the farm in a new and clean can .ANd after spending more money they told us everything we needed to know and showed us what had happened . We had paid for hightest as that is what we have always used as per the owner manual but the fuel supplier brought 87 . We never told the lab WHO's gas it was or the octain content they told us who's gas it was and what the octain level was and the chemist plum told us that that gas is not blended for a industrial engine working under extream loads. and that combustion peak heat is wa off the scale for emmission and that the gas contained MTB and that made it's owen oxygen and cause the fuel mix to lean out and anybody that has ever raced knowes that there is a fine line between leaning out a mixture for power and then going one littel step over the line and melt down. Now back to the valve issue I H had a ton of problems with the burning of Exhaust valves on the new 4-6 cylinder engines and they found that it was littel deposits of ash that came from the oil and would torch a neat little Vee in the valve and they,here again will do this in a heart beat. another lession learned the hard way As we were hard headed about oils for a long time . Now that we play the game we have not had any problems with valves by using the low ash oil yea it costs more but i don't have to be pullen heads off and doing valve jobs. We work the snot out of our gas tractors and they run like a swiss watch , they are fed 93 octain gas get the 30 weight low ash oil and reg. oil changes on time with in a couple hours and we get good service out of them. The tractors are paid for and to replace them with something newer it may be nice but since we have not hit the LOTTO and we know what we have and just going out to a sale and finding something newer your buyen something you know nothing about. ANd the last thing i need is to get the exp. of removing every nut and bolt out of one to make it what we want. I try and give GOOD info from my years of working on this stuff and help all of you get the most out of your toys .

Replies:

Add a Reply Name: E-Mail: Subject: Comments: Optional Link URL: Link Title: Optional Image URL: Optional Video Title: Optional Video URL: Email Notification: If you check this box, email will be sent to you whenever someone replies to this message. Your email address must be entered above to receive notification. This notification will be cancelled automatically after 2 weeks.

TRACTOR PARTS	TRACTOR MANUALS

We sell tractor parts!  We have the parts you need to repair your tractor - the right parts. Our low prices and years of research make us your best choice when you need parts. Shop Online Today. [ About Us ]