We have to remove the engine from a John Deere 750C dozer with the powertech 6068. Can anyone tell me which bolts need removing to seperate the transmission from the engine? We have the JD service manual but it really doesn’t say anything about the procedure or identify which bolts. AI mentions removing a plate on bell housing to access coupler bolts. What coupler bolts are they referring to? Help is much appreciated.
Do you have the cab / ROPS jacked over? If you do remove the 12 bolts around the outer edge connecting what would be considered the clutch housing to the flywheel housing. There should be (8) 3/8X1.25 and (4) 3/8X2.5 . You can support the pumps by putting a 4X4 or piece of angle iron across the platform and holding them up with a ratchet strap. If the cab / ROPS is not tilted over be very careful in doing so. The procedure should be on a decal inside the right rear access door.
Thank you for your reply. Yes the cab is tilted over. We did put a come along around the pump at the cross brace thats situated above it. Will another be required a bit farther forward? I’ll try getting some pictures of the situation. But is what you are calling the clutch housing include the two bosses going out to the side frames then bolted with quite heavy bolts straight up abd down? I would have thought that piece stayed wuth the engine, but I sure could be wrong.
The rear engine mounts are bolted to the sides of the flywheel housing ( closest to the engine block ) and you can remove the two large up and down bolts. That housing stays with the engine. Are you replacing the engine?
Yes, need to remove the engine to have the crankshaft journals ground, or to replace it. Theres some main journals that are scored pretty good. Thats what I expected, for the flywheel housing to stay with the engine. Im not seeing what you might consider to be a clutch housing though, unless Im just not seeing the parting line in the flywheel housing? I do see 4 or so big bolts, probably 3/4” or 19mm size. And a few smaller bolts that look like theyd go all the way to the block. Then a nut on each side of the pump where its bolted to the plate at the rear of the flywheel housing. I’ll work on getting pictures.
Remove bolt #'s 8 and 11 ( 12 bolts total ) Don't remove bolts #11 holding the pumps to item #9.
Thats excellent help and much appreciated Sir.
So that Im understanding correctly, just the 3/8 bolts around tge rim come out? Then pull the 4 motor mount bolts and slide them apart?
Yes, that should be it, don't get rough with it in case I'm forgetting something. It looks really clean. I've worked on lots of 750 and 850C's. I had been working at a Deere dealership for around 10 years when they went into production. It was quite a learning curve after working on the hydrostatic crawlers built before the C's. The C's are easier to work on mechanically but can have some really tough transmission problems to figure out but the earlier ones can as well. Post again if you need some help, I had to give up the repair side of the business about a year ago and just didn't think I could handle an inside job. Good luck, I'm glad to help.