3pt not working, I broke something

[marklbota]

B2710 with HST, I was using post hole digger and tractor was really laboring, our soil is really rocky. I heard/felt a loud bang so I stopped. Here's the situation:
* 3pt arms won't raise. they dropped to the ground freely and I can raise them by hand, but the hydraulics won't lift them.
* PTO shaft turns, but I can't put a load on it so I don't know if it really works.
* The tractor will move but it makes a bad noise like there are parts clanging around in the transmission.
* I have the proper shear bolts on the auger, neither of them failed but were very bent. The bolts on the PTO shaft did not shear either.

Trying to decide how to proceed, it seems almost certain something broke in the rear PTO section of the transmission. I also think the clutch may have been slipping while this failure occurred. I noticed after the loud bang when I looked the other direction that there was smoke coming from under the tractor. The wind was carrying it in the opposite direction I was looking when things broke, so I'm not sure how long that was going on. The noise when I drive it might be some broken part that ended up in the transmission where it shouldn't be. I'm reluctant to drive it given the noise it makes, it's only a few hundred yards from the shop so maybe I can tow/shove it into the shop.

Any advice on diagnosing this before I tear into it is welcome.

 

[whitetiger]

I would start by removing the 3 point cover over the rear differential to see if the linkage broke and dropped a piece in with the ring gear. That would explain the lack of lift and noise.

 

[marklbota]

Thanks, I've been staring at parts diagrams and the service manual. After I tow it into the shop I'll see if I can get that cover off.

 

[Russell King]

I don’t think I would try to drive or pull it. Maybe get a wrecker to put it on dolly and then tow it into the shop. I would be worried about breaking a gear tooth.

The smoke was probably the clutch plate slipping on the flywheel since the pto was locked up?

 

[marklbota]

When I try to tow it, the rear wheels move a bit then lock up and skid, same going backwards. I tried it with the HST lever in neutral and in each gear, same behavior. Pushing clutch in doesn't help. I decided to put it in low gear and go slow. It makes a repetitive noise that sounds like something grinding, but it's not too loud and I only had to go 100 yards. So it's in the shop now.

 

[marklbota]

I don’t think I would try to drive or pull it. Maybe get a wrecker to put it on dolly and then tow it into the shop. I would be worried about breaking a gear tooth.

The smoke was probably the clutch plate slipping on the flywheel since the pto was locked up?

I didn't have any choice where it was located, I couldn't get a wrecker in there. I think you might be right about the clutch.
Anyway, it's in the shop now, I wish I didn't have another project I have to stay on, I'd love to start working on this because it's bugging me.

 

[marklbota]

Got the cover off the 3pt area, here's the photos. Looks like the initial failure was the arm on the rockshaft that the piston presses against, the casting broke in half. Also damage to one tooth on the ring gear and the cage for the pinion gears, probably from the broken casting that fell onto it. So the only good news is it looks like all the damage can be fixed from the back and I won't have to split the tractor. Can't tell if there's any damage to PTO drive because the shaft just passes through this area and wasn't involved. The gears for the PTO are further forward in the transmission. I did try the PTO when the tractor was running, so hopefully it's OK.

 

[hagrid]

Oh my...

 

[rbargeron]

Got the cover off the 3pt area, here's the photos.

may not be critical - control valve lost a chunk - need to find it? Best luck with all the wrenching.