JD 850 yanmar Engine Crankshaft

DallasA · Jul 15, 2009

I am in need of a crankshaft or engine for a John deere 850 with a Yanmar Diesel engine. John Deere has told me that it is no longer available thru them. Can anybody help me? The engine is a 3T80J 605-881-3300 Dallas

Ron D. · Jul 15, 2009

Is it broken, or can it be machined? If it can be machined I would take it to an engine machine shop.

If it's broken, I would contact Hoye Tractor, a frequent contributor to this site and great people. They might be able to point you in the right direction. Others that might be able to help are LMTC and Tractor Ernie, all are knowledgeable.

Good luck, let us know what happens.

DallasA · Jul 16, 2009

It is not broken. However I took it to a machine shop and they cannot grind the journal within specs. They would have to take 040 off in order to finish it. Bearings are not available for that amount. I will contact Hoye Thank you. Dallas

cowboy357 · Jul 16, 2009

I,m not Posative but I beleive the right shop could weld up the Journal & regrind it back to specs . I,m Pretty sure someone here said it could be done, But I cant find the post. Best of luck. Bob

LMTC · Jul 16, 2009

DallasA, check your messages on this forum.

cyberflyrg · Jul 16, 2009

Crankshaft welding is a common technique in the racing business, we screw up cranks all the time with spun bearings, blown engines, broken rods, etc.
Id check with your local speed shops, maybe NAPA, or a crankshaft rebuilder. It takes a special welder and crank grinder to do this, the welding is actually done underwater and with an eccentric machine that can follow the crankshaft as it rotates around. I had a chevy 454 crank done last year and had all for the journals done for $355 and had them brought back to std. size. That crank can rev at 7000+ RPMs and works perfectly. Hope this helps.. ron.

cowboy357 · Jul 16, 2009

Thanks Ron , for verifying it can be done . Bob

Petrena Engine Builders · May 9, 2012

If you buy a crankshaft,New or used you should take the shaft to a Machine shop and have it check for size,cracks,and straightness.You other crank can be welded ,or check salvage yards in South Georga (pavo)they have a huge inventory. The block also need to have the Linebore check if it is stright. I have been a Machinist for twenty Eight years,serviced and repaired many engines. God Bless.

Don