PTO Problems (Help)

[DLJester]

Hey Ya'll.
I have a 2012 T4.75 Powerstar with 1150 hours. I bought a 12 foot bat wing shredder that is rated for a minimum of 40 HP. My NH PTO will not run it at idle, it takes about 1800 rpm's (way to high) to engage and stay engaged (if not it kills my tractor in dramatic fashion) once it's engaged it runs it fine until I shut the PTO off (manual not electronic) and then the PTO remains engaged. I have to kill the tractor and let it sit till the oil cools (deductive reasoning) then I can move the PTO to the brake (off) position and it will disengage. The clutch brake holds when the oil is cool but will not hold once it has been run awhile. I've changed the hyd oil and filters and there is no change. I had an 8 foot shredder last year and it did the same with it. Any ideas would be appreciated, hyd pump, wrong oil (I used a GL4 recommended by NH, from NAPA), oil flow restriction, I am at a loss. Thanks
DJ

 

[JC-jetro]

Not familiar with your rig. Do you know if you have " live" or " independent " PTO? if independent then do you know if you have a "wet clutch pack" for your pto? if the latter is correct, you might have put much load and stress on the clutch and as it slips then it sure could destroy the clutch pack. How is your PTO clutch activated? mechanical? hydraulically? or electric over hydraulic?

JC,

 

[DLJester]

JC
It's a fully independent wet clutch PTO. It is mechanically engaged by a lever. Once it gets hot the lever can be moved to the off position but the PTO light will remain on. Tractor must be shut down and once it cools I can reengage the PTO and then move it to the off position and the light will go out, and the tractor can be started again. I'm not sure if its the the clutch pack, the brake band, weak hydraulic pump, clogged line, or what.

 

[Roadworthy]

A PTO over run clutch might help your situation.

 

[kthompson]

A PTO over run clutch might help your situation.

How could that help? Have never used an external overrunning pto clutch.

DL, have you verified the lever is moving the linkage to release the pto? Look for stick or something else interfering with the linkage or being rusted.

 

[JC-jetro]

JC
It's a fully independent wet clutch PTO. It is mechanically engaged by a lever. Once it gets hot the lever can be moved to the off position but the PTO light will remain on. Tractor must be shut down and once it cools I can reengage the PTO and then move it to the off position and the light will go out, and the tractor can be started again. I'm not sure if its the the clutch pack, the brake band, weak hydraulic pump, clogged line, or what.

I did check with tractor data to get a bit more familiar. You do have a wet clutch pack. You will have an inner pto input shaft that is directly splined to the flywheel and that independently turns any time engine is turning. The outer input shaft is splined to clutch disk that used for locomotion either by gear or HST transmission. You will have a valve that opens up hyd fluid to push the clutch pack together and that engages the clutch, when you put the PTO lever to off that should open the valve and bleed off the pressure off the clutch pack, hence disengaging the pto. You need to verify if the control valve works like it should. You most likely have some adjustment on the lever to adjust valve closure or opening. Your problem might be that, where the valve is not fully opened to disengage the pto clutch and when you turn off the tractor, hyd fluid gets cold and bleeds off the pressure and disengage. Few pics would be great.
,

 

[LouNY]

Hey Ya'll.
I have a 2012 T4.75 Powerstar with 1150 hours. I bought a 12 foot bat wing shredder that is rated for a minimum of 40 HP. My NH PTO will not run it at idle, it takes about 1800 rpm's (way to high) to engage and stay engaged (if not it kills my tractor in dramatic fashion) once it's engaged it runs it fine until I shut the PTO off (manual not electronic) and then the PTO remains engaged. I have to kill the tractor and let it sit till the oil cools (deductive reasoning) then I can move the PTO to the brake (off) position and it will disengage. The clutch brake holds when the oil is cool but will not hold once it has been run awhile. I've changed the hyd oil and filters and there is no change. I had an 8 foot shredder last year and it did the same with it. Any ideas would be appreciated, hyd pump, wrong oil (I used a GL4 recommended by NH, from NAPA), oil flow restriction, I am at a loss. Thanks
DJ

Am I reading this correct "you are using a GL-4 fluid".
To me a GL-4 would be an 80-90 type gear lube.
Your tractor should I believe be using a hydraulic/transmission fluid such as Master Tran Ultraction,
which is a New Holland label for IH Hytran.