JD 970 PTO clutch

[JC-jetro]

Rojo,

With the engine OFF, pto coupler (lever) engaged along with clutch pedal fully pushed in all the way, then one can try to loosen the pto stuck clutch by getting a pipe wrench on the pto shaft and rotating it back and forth. in condition above the pto shaft should not rotate if clutch is stuck.

Again I emphasize " engine off" ..I never touch any part of PTO with the engine on other than engaging it from the tractor seat.

JC,

 

[Keoke]

JC, the pto drive line is designed to free-wheel when driven from the pto end in one direction. This is to prevent mower blade inertia from driving the engine rpm when slowing down engine. Also, turning pto shaft while engaged will simply turn the engine over and is not likely to break loose a frozen up clutch disc unless you find some way to lock engine flywheel or crankshaft up while turning shaft.

take care,
keoke

 

[RoyJackson]

It's possible rigging a cutter to the machine and popping the clutch (tranny in neutral) might do something. That's pretty safe and it might be enough of a shock load to break the plates free. If you try this, just let that cutter stop rotating (betwen the times the clutch is popped) for maximum effect.
I'm suggesting using a cutter as those heavy blades will provide the most inertia of any PTO driven implement I can think of.
Good luck!

 

[zzvyb6]

When this happened on my 1070, I put the 8' mower on and drove into a thick clump of grass + anthill. With the clutch in, it didn't take very long to overload the clutch rust.

This means you have to start the machine + mower combo together, but I'm sure you can figure it out....

 

[Keoke]

ZZvy, very good idea for heavy loading and breaking free the frozen pto clutch plate.
Roy, the pto drive line has a "sprag" unit built in. This allows the engine to turn the pto shaft but does not allow the pto shaft to turn the engine.
This the same sort of unit (over-running clutch) that you find in starter drive gears (eg. starter can turn engine but engine can't turn starter).

take care,

 

[JC-jetro]

JC, the pto drive line is designed to free-wheel when driven from the pto end in one direction. This is to prevent mower blade inertia from driving the engine rpm when slowing down engine. Also, turning pto shaft while engaged will simply turn the engine over and is not likely to break loose a frozen up clutch disc unless you find some way to lock engine flywheel or crankshaft up while turning shaft.

take care,

keoke

Keoke,

Yes.. I do realize the one way clutch operation. I was hoping in one direction the force to break sticking plate loose is less than torque required to turn the engine and if the engine turned!! so be it as long as the gear is in neutral as Roy suggested. I don't think you can turn the flywheel fast enough to get the engine started. Using a brush hug is a good idea too.. I would make sure to disengage the pto coupler, hook on a brush hog, start the engine and raise the the implement, go where I want to test the procedure, lower the brush hog on some stand/logs or what ever, turn the engine off, engage the pto coupler and start the tractor. At that point I start the tractor and brush hog at the same time. I then move to a safe place and lower the brush hog on to some bush or low sapling hoping for the shock load the break the disk free while pushing the clutch plate all the way down. Wouldn't you think that may work?

JC<

 

[rojo]

I tried adjusting the clutch and that did not help. Next I tried the pipe wrench on the PTO shaft Like JC suggested and that did not help either. I was thinking I would hook up the brush hog and go cut brush, but I ran out of time. When I got in, I see the same suggestion was made here so next weekend I will be trying that. Thanks for all the help, will let you know what happens next.

 

[zzvyb6]

You don't want a shock load to break a clutch free. That may break the clutch material. All you want to do is gradually overload the friction surfaces that are engaged. Its not the entire clutch pack. Probably just a few square inches or less of surface. Then you want to feather the clutch when it cuts loose so you don't rip up the clutch plates or scratch the metal surface(s).

 

[rojo]

I tried brush hogging today and several times I backed into heavy brush with the clutch pushed all the way down and it never released. So I guess I will have to break the tractor in half and see what is going on. Probly will wait a little while longer and maybe try using the post hole auger first.

 

[Keoke]

Rojo, there is a lot of kinetic energy (inertia) stored in those rotating Bush Hog blades. Soo, in heavy brush, try bringing the engine speed down to idle and while going forward (down-hill) into the heavy stuff, with clutch fully down, run the engine up to full throttle real quick. This should put a accelerative sheer load on the pto clutch.
Let's hope you get lucky. Hey' it's no fun splitting that tractor.

take care,