PTO slip clutch adjustment

[brohloff]

All good comments but still no progress on opening or adjusting this SC. Can't see that the nuts do anything as they are 3/16" away from the plate through which they protrude.
That outer plate can only move inward(if it moves at all) as every other side slot has an indented edge acting as a retainer to keep it inside. Viewing through the slots there does
appear to be 2 disk materials or plates but nothing is even pryable…It's solid.
This pto shaft is likely about 12 yrs old and it's possible if it's never been opened or maintained it's all frozen up.
I flushed the nuts back to the studs and rapped on them with a hammer and nothing seems to move - solid. Those are deep 13mm nuts and perhaps that is why the are there. For
rapping to unfreeze (maintain?) the interfaces…… A thought anyway.
Anyway, at this point, unless I have some great revelation, I'm back to keeping the original shear bolt OEM pro shaft…. I "get" how that thing works !!!! Though maybe a SC would be an upgrade.
Back to KISS.

 

[brain55]

There is no adjustment on the clutch. The nuts can be tightened down to compress the Belleville springs so you can bend the housing back out of the way and remove the discs and springs. Once removed you can remove the nuts and disassemble discs and clean off whatever rust or dirt there is and then reassemble in the reverse order. I usually use a pipe wrench adjusted to the right distance to grab the side of the housing and the dimpled in portion and bend it back out far enough to clear the disc assembly.

Brian

 

[greg_g]

Agreed, it probably uses Belleville springs rather than the more common compression coils. Four nuts are sufficient to distribute pressure on a Belleville. Agree as well, that the reason you're at an impasse - even with the nuts loosened - is that the disc and plates are likely frozen. Again, I suggest you mount the tiller, connect the PTO shaft at both ends, keep the nuts loose, and use horsepower to try and break them free

//greg//

 

[bigtiller]

I had a JD 450 tiller for several years, here is how I adjusted the clutch.

Loosen the 4 nuts. Then hand tighten them finger tight. With a deep set socket and short extension, tighten all 4 nuts 1 revolution at a time. Keep track of the number of revolutions and keep all 4 equal. Connect the pto shaft to the tractor and engage the pto {engine OFF) and try to move the tines. When you can't move them any more you are close. Tighten the 4 nuts another revolution.

Write the number down so you can do it again next time a little faster.

Put the tiller in the ground and watch the tiller working, looking for smoke from the clutch. After about 20 feet check the clutch housing for heat. Keep checking it every few minutes.

You may even want to place a 3 ft. 2x4 in the tines to replicate a root or rock to see how slow the clutch slips. You want it to slip just enough to not kill the engine, giving you about 2 seconds to react and shut the pto off when tilling.

If you tighten the nuts too much, you will in effect, lock the clutch tight enough that it won't slip. If you use a second tractor with more or less horse power, you may need to adjust the clutch for it.