4020 PTO spinning again

[Dweitzel]

Had my transmission leak fixed on my '65 Powershift 4020. The tractor would leak from the bell housing area anytime I ran the PTO, but not running or pulling equipment without PTO operation.

Repairman found what he described as a cracked plate in the 1st clutch pack letting fluid press against a seal?. Leak is gone, but within about 20 hours of use with 15' bushhog and round baler, the pto is spinning again while off. Until I had the tractor split, the PTO was rock solid as I had the brake lining repaired about 5 years ago. I always use an over run clutch on the pto.

I did NOT look at the PTO for movement when I got it back to the farm. I always turn the tractor off to hook up the PTO and hydraulics. I checked under the steering wheel and the linkage is all in good shape, tight and free of debris. The PTO check plug reads out 150 psi when the PTO lever is engaged and 0 psi when turned off.

When I got the tractor back, I drained and refilled the transmission with 15 gallons of Hyguard fluid. Filters looked good and screen had very minimal debris on it. Nothing I would worry about and no metal shavings I could see in the drained fluid.

I do remember shifting from 7 to 8th gear on the road after changing the fluid and I heard what sounded like the 3 point arms clacking against the wear plates behind me. Again, I did not look at the PTO, but I do think I had it running when I was test driving the tractor.

Any ideas? Would splitting the tractor to the 1st clutch pack affect anything with the PTO? Would I have damaged anything shifting from 7 to 8th gear with the PTO running?

Thanks for any advice you could offer.

 

[Dweitzel]

Another thought, if I run the RPMs below 800 or so, the PTO will slow down and come to a stop. The PTO will NOT turn if I hook an implement to the PTO and I can stop the PTO with a 2x4 and some pressure, but not at higher than 1000 RPMs. The PTO will look like it wants to slow and stop if I operate the 3 point lift arms up and down, but it only hesitates for a second or two and then continues to spin.

Also when I start the tractor, the PTO usually does not spin until I place it in gear for the first time.

 

[wore out]

(quoted from post at 08:11:59 06/24/21) Another thought, if I run the RPMs below 800 or so, the PTO will slow down and come to a stop. The PTO will NOT turn if I hook an implement to the PTO and I can stop the PTO with a 2x4 and some pressure, but not at higher than 1000 RPMs. The PTO will look like it wants to slow and stop if I operate the 3 point lift arms up and down, but it only hesitates for a second or two and then continues to spin.

Also when I start the tractor, the PTO usually does not spin until I place it in gear for the first time.

Verify that PTO linkage from lever to clutch valve is properly adjusted and not binding on debris down inside the steering pedestal on top of the clutch housing.

Check PTO clutch and brake pressures at the test ports in the clutch valve. There should be NO pressure at the PTO clutch test port when the PTO is "off".

The C1 and C2 clutches and the PTO clutch are all "stacked" together and there's a number of ways that pressurized oil can leak to where it's not supposed to be, one place is the sealing rings (4 used, Key #6) on the transmission pump "manifold" (Key #Eight), also at the gasket between the pump haves, or at the pump mounting gasket, or gaskets or other issues in the valve body..

 

[Dweitzel]

Thank you for the diagram. I'm assuming this is the C1 clutch pack? Any other trouble places that the oil can leak past other than the #6 seals mentioned? Thanks. Just trying to get a better idea of what to replace when this is split again (for the 4th time).