Super A-V clutch joint, noise and poor release action

[ccaissie]

Back for more punishment...

OK, so there was one bolt missing on the clutch drive joint. Lock washer failed to lock after 67 years, and nut came off. Impossible to repair in place, so I broke it at the tranny. Replaced the transmission input seal, and gasket while I was in there. Replaced the rubber washers, and used Grade 8 top lock nuts on the joint to make sure the parts don't ever loosen at least in my lifetime.

Went together well. No banging. Now I'm back to a previous problem, clutch sticking and having trouble engaging/ disengaging.

I had sprayed brake solvent onto the clutch drive shaft and disk splines, and that took care of the problem before I repaired the joint. Shifted fine, almost no spin-down time shifting...all good.

Now, after fixing the clutch joint, it's back and I can't make a difference by freeplay adjustment, more solvent, some WD-40, rapping and banging with a rod on the splines and clutch hub....nada.

So, again, here are the symptoms. It won't go into gear except with a quick hard throw which grinds and just is not right. In neutral, clutch pedal depressed, I can hear the gears in the tranny spinning erratically, some grunting noises as the clutch semi engages...kinda off and on. Actually, once in a while it WILL GO INTO GEAR, smiles appear, then it won't.

When I shut engine off, I put it in gear, and restart it, clutch pedal depressed, it's perfect... FOR ABOUT 2 SECONDS, then it resumes it's noisy intermittent grunting and the tractor creeps. Releasing the clutch...... the grinding noise worsens for a moment as the clutch grabs more, then it's perfect, no noises, driving ahead like normal. Can catch it into reverse if rolling back, etc. BUT, throw the clutch pedal down, and it's still trying to creep forward, and now making the noises.

So, clutch disk is dragging on the flywheel, or the pressure plate, or the pilot bushing is seized, and I can't seem to free it. I'm hoping it's just a binding of the disk hub on the splines, but expect that to improve, now that there's some solvent on it, and it worked before. It may loosen in time. For now, farmer Brown is going to use it, doing his longest rows, restarting the engine with the tranny already in gear and all that.

Is the disk coming apart? delaminating/ rivets falling out and getting caught? Seizing on the disk splines? Pilot bushing?

So, break it apart, eh?....I did notice that the clutch fingers were not all showing the same action with the clutch being depressed. It looked like one of the fingers had slight clearance ((1/32") and a bit of slack a the TOB, while the other two fingers were already contacting the TOB. I adjusted it a couple of turns in both directions, and saw no change in the action there or in the grinding symptoms. I'll review the bench clutch adjustment procedure, but I'm pretty convinced that it's clutch time.

Any words of encouragement? Is this interesting? OR NOT.

 

[andymd]

could be the pilot bushing is wore out and the side of the disc is dragging on the side of the flywheel

 

[ccaissie]

Yeah, that makes sense. Still have to break tractor...

 

[Janicholson]

I agree. Two more potential issues. 1} spline wear on the clutch shaft can cause the disk to be pushed toward the FW causing drag. 2} The disk can be bent at the hub from the shaft being out of concentricity (bolt issue). If the splines have some wear, using a dremel tool to remove 1/16" of the teeth on the clutch hub can allow freedom to release. Jim

 

[ccaissie]

Great replies, thanks.

The missing bolt/clutch joint issue made the shaft wobble, so the idea that the hub could be bent makes sense. It wouldn't take much, as it was already binding and was freed with lube. Now it's pretty chronic, and not willing to behave. Will run it for a while and see if it improves/frees/wears itself in.

Important to side dress the immense cabbage crop now, so Farmer Brown will have to limp along for a while before we split the ol' girl.

Thanks,
C

 

[Andy Martin]

It may be as simple as the clutch lining coming off the clutch and getting caught around the edge of the flywheel. Large areas of missing material could also make the fingers show different heights.

 

[ccaissie]

Yeah, could be disintegrating. Will yank it when I can.

Thanks,
C

p.s. will issue full report/photos when I fix it.

 

[Curt Cooke]

Break it in two again. Since it's such a lot of work to do so and I wouldn't want to do it again, I would replace the clutch disk and pressure plate and have the flywheel resurfaced. Adjust the release fingers according to the specs given in an IT or other manual. That adjustment is critical but even more critical is that they are all set at the SAME distance. Examine the pilot bushing and input shaft relationship and if bad, replace the bushing. Look carefully at the end of your input shaft and at the bore of the crankshaft and see if there is any evidence that the two surfaces have come in to contact with each other. If the length of the input shaft has changed, that is made longer, or the crankshaft has been replaced at one time, it could be that friction exists between the end of the input shaft and the bore in the crank. This will cause the input shaft to continue to spin even with a perfect clutch disengaged. Seen this happen when I had to have a power unit crank bored for an input shaft and the bore was not quite deep enough. The slightest contact will make for trouble.