D6 9U Dry Clutch Flying Apart

[d7doug]

Purchased the 9U last summer, worked it a little, the dry clutch keeps flying apart. Some parts came through the bell housing, yikes.

My questions: Can I do a complete rebuild of clutch, and are all parts
available?
Can I change it to a (wet clutch) or a complete (updated
dry clutch?)

Should I just use it for a parts cat for my other 9U that has
a wet clutch?

Thanks for any and all input D7 Doug

[gemdozer]

If you change your dry cluch for wet you will have to changed all the belhousing ass. and some linkage you could check before your cluch and am still have some use parts.

[Old Magnet]

Pretty sure all the usual wear parts are still available from Cat and some aftermarket. Last rebuild I followed was about a year ago.

Changing to wet clutch means changing flywheel and the transmission input shaft as well as the parts that make up wet clutch assembly itself.

[First Cat]

I rebuilt mine last fall and only had to go to CAt for 1 part.

[edb]

Hi d7doug,
be aware that early S/No tractors require that the engine to the clutch be aligned with shims under the front and rear engine mounts or failure of the links etc. will occur. It could also stem from bent and/or twisted frame rails, or badly worn engine front support bearing.
My Serviceman's Reference Book is too water damaged to get clear scans to post for you so I hope someone else can help out here.
Hope this helps.
Cheers EddieB.

[Billy D7 4T]

Radial and axial alignment per the serviceman's reference book, if the engine has been out, and the same shims are not used, or for some other reason it's out, you can also check the condition of the pilot bearing on the clutch shaft, if that bearing is toast, it can and will wallow out the driven plate, cause excessive vibration, and about 10-15 hours of run time + or - the heavy woven drive links will eventually fail. They seem to tolerate quite some abuse, and are very strong, unless age can weaken them, or they have been installed backwards, but if that bearing is out, won't take long, definitely need to grease that one on time, you should be able to remove that clutch in a few hours, check the friction materials on the clutch plates, and clutch brake, good time to have those relined if thin, SRB covers it pretty good.

[OzDozer]

Here are better scans of the alignment process listed in the D6 Servicemans Reference Book, as previously posted by EddieB ..

Page 1 .. http://img246.imageshack.us/img246/3...alignment1.jpg

Page 2 .. http://img246.imageshack.us/img246/5...alignment2.jpg

[Old Magnet]

Billy,
The D6 dry clutch does not have a crankshaft pilot bearing.
Does have a bearing in the center plate.

[Billy D7 4T]

Uhhh..... your right, well but ummmmm....... my bad with the terminology . I was looking in a parts catalog for the previous series, within the military tech manual TM5-3100 dated August 14, 1943 covering tractors 4R680 & up, 5R903 & up, 1B4368 ( bearing assembly w/roller 1B4369, race 1B4370) 6B9148 is the shaft, with the sleeve 6B9104 that acts as an inner race, for that bearing in the plate assembly 5B2717. I know the release mechanism changed within these tractors, but figured the dry clutch is about the same for the 8U/9U series.

That is one fitting to remember to grease correctly ( also don't want excess flinging around in there) after seeing the mess it makes of this type of clutch assembly, the sleeve must be hardened, as it protects the shaft, but does a number on the driven plate where the bearing is, when the bearing fails, and you keep running it, vibration also makes the fenders on the tractor flap, and all sorts of things come loose, it's very noticeable from what I saw on my D7. I think once you first start to notice this vibration and those links start to rub on the bell housing, you know it's time to get in there, and it does seem, to give you enough run time to get the tractor where it needs to be to work on it, I was amazed at what those links actually could tolerate, especially with 60+ years of age, as this one never saw much use, or any grease in that bearing long before I got it. Eventually those links came apart and unwoven, looked like a big ole mouse nest, well this had been going on, mice had taken those drive link scraps into the intake, they came out the exhaust and were smoldering when I first got this one, thought it sucked a rag through or something, turned out to be drive link material that was now bits of string.

[chinookhawk]

I have a D6 9U that was still running when I got it with a "weak" clutch. Tore it apart and 2 of the 5 drive links were attached and one of the shackles was nearly ripped off. The Clutch Plate Assembly 5B2717 has a crack through half of it and the bearing probably went out 15 years ago. Bearing $267 at CAT Aftermarket links $36 a piece. Does anybody have any advice or guidance on where to acquire the best parts for the best price?

Mike