1997 B21 Rear Diff

[Jason1981]

Hey all new to the forum and i realy need help, trying to build a garage and my trator B21/1997 decided to start acting up. Here`s the issue, there is a very loud knoking sound comming from under the seat when the tractor is under load and i can feel the rear wheel (binding ???) even if i take it out of gear and i puch myself around with the backhoe it still does the same sound, both wheels off teh ground and the diff lock engaged same sound, no diff lock one wheel on the ground same issue, i'm thinking it's a problem with the rear diff but i am at a loss at how to get in there and check, can anyone point me in the right dirrection ???


thanks for your help

Jason

 

[DJ54]

Not how to check, but may have somewhat of an idea what the problem may be. Most operator manuals tell you NOT to engage the diff. lock, while the wheels are spinning, but, rather stop, engage the lock, then go. If you engaged when spinning, it may have damaged the part that engages it internally. On a Massey-Ferguson 180 IO had, the piece that engages the lock was made of like a pot metal/cast aluminum, making it the weak link, having it break before anything else.

However, years ago, a buddy of mine turned his John Deere 4020 over to some younger fellows that had helped them in the past, to disk crop ground, while he took a break to eat. There was a muddy spot in the field, and he told the guy to lock the differential, before getting to that spot. Apparently he forgot, and engaged it when it started spinning. After doing it more than several times, it cleaned the ring & pinion, and the tractor was down for 4-5 weeks, waiting his turn to get into the mechanics time schedule, and getting parts, plus repair time.

Could be you broke a tooth of either the ring, or pinion gear, and the knocking noise may be one gear jumping over the broken off tooth. Purely speculation, from past experience of someone else.

 

[Jason1981]

That's what i am thinking also, even if i try not to engage the diff lock when the tractor is spinning, is there an easy way to verify if the rng and pinnion and broke or am i going to have to split teh tractor and work my way back to the Diff ????

 

[DJ54]

I'm not familiar with that tractor at all, but, your going to have to remove the top cover of the diffy, to have a look inside.

 

[Jason1981]

I'm not familiar with that tractor at all, but, your going to have to remove the top cover of the diffy, to have a look inside.

Well I tore into not today all day and it is the rack and pinion on the rear diff that are all chewed up ... nice little job splitting the tractor and getting in there. Anyways I was able to get the rack out but I don't know how to remove the pinion any ideas ... I guess I cod post a couple pictures tomorrow morning to show where I'm at with the disassembly.

 

[dfkrug]

Have you separated the final drive case from the main transmission case?

Where is "entrelacs"?

My 1998 B21 had a bad ring and pinion gearset, too:
http://www.tractorbynet.com/forums/...complete-driveline.html?highlight=b21+rebuild

I think post #18 shows the diff.

 

[DJ54]

Ouch....