thinking about a 706G

I have been thinking of picking up a 706G to do some bigger jobs that would be better then my 606. I would go the diesel route but I know pump parts are getting hard to get and costly. I have looked into most of the maintenance issues with these. what my question is about the gas engines having issues with fuel/octane. I am just trying to get a better understanding of what is the actual engine failures. I understand from most posts if it is going to be working hard 93 octane/ alcohol free is the best.


When they fail is it piston/ sleeve scoring, holes in pistons, burnt valves?

What happens is the piston will super heat and swell , when this happens it will expand larger then the skirt of the piston that will have some place between .0035 to .0045 clearance and score the sleeves and trash out the piston .myself i have run 706 gassers since 1983 and go along just fine with them till they started messen with the gas. We have several guys around here even with 4-560 gasser having problems with the same thing that were running the reg. , but can get by on the socalled 93 as those tractors were to run 89 when new . Yep there will be those that will tell ya i don't know what i am talking about , hey i only work on tractors for a living and have also built many lets go play engines over the last 55 years . So when and engine problem does happen i know what caused it . YEp i loved the 706's and i have owned bought and sold more 706 gasser then all four I H dealers ever did while they were in business. During my days of the buy sell and running across three states buying i bought a lot of them from the dead rows and brought them back to life and sold them with some going to my close friends that gave many years of good service till the issue of the gas . The ones i sold went to small dairy operations for a good reliable start in any weather to do what ever came up . MOst of the ones i bought did not run and had T/a's out . 99% of the time the reason they did not run was due to dead batterys and a non working charging system along wit a bad T/a . The chqarging systems were rebuilt , new battey , T/A's were replaced with a Hy Capacity Std duty T/A along with all new bearings IDPOT input shaft seals and bearing . MCV was rebuilt with a NEW MCV pump . Hyd. system's were tested and if needed a NEW pump , PTo unitys were pulled and checked and if Ifyy they were rebuilt , What ever they needed they got and OH i gave Warranty on all that sold local . We all got along just fine with them doing what they were built for . Myself all my Hobby farming was done with a 706 gas i pulled a 710 4x16 plow a 370 13.5 foot disc and a four row 1240 John Deere plateless planter with mine . I have worked on so many 706's i do not need to look ion the books for the spec. i know what tools i need for what job i am doing on one and it is a one stop at the tool box for that job. Our problem with the gas really hit us hard here on the last change on the gas as we had two go down a day apart on two different farms and i am NOT fighting it anymore . Now i am fighting the idea of doing something way off the wall and taking my one friends and pulling that engine that had a ton of work done to it and putting in either a 6.9 or a 7.3 and re badging it a 7068 . I am now looking for a mock up engine so i can do some figuring .

The alcohol free is not important. The fuel should be 92 93 R+M/2. Make sure the valves get adjusted. Run low ash oil to avoid valve head deposits. Jim

Got one.
I burn only 91 or highest octane gas I can find.
Use low ash oil.
Pulls like a mad badger and really wraps up!

The 310 german with it's German Bosch pump is spendy to fix,with many pump parts becoming obsolete. The 'American. D282 with RooseMaster pump is common as hens teeth.Costs about $1000 to have one rebuilt.

My FIL bought a 706G brand new and used it as his main field tractor until the new 966 showed up in
the early 70's. Since then it still gets frequent use as the only loader tractor on the farm.
He's always gotten along fine on regular (87 octane) fuel, including E10 in the recent years. For
Nebraska test #957 this tractor used gasoline recorded as "Motor 84, Research 92.2" which would be
88.1 octane using today's (R+M)/2 rating method.