Pto keeps turning

[toddsuff]

I have a JD 3520 with about 250 hours on it. Hydrostatic Tranny.

The problem I have is that the rear (only) PTO keeps turning when I push the switch in, but at a reduced speed.

I took it to the local dealer last year. They kept it for well over a month. I paid over $800 for half of the repair JD picked up the other half since it was out of warranty as a customer accommodation. The second time I used the tractor the problem returned. I contacted the dealer and he said to bring it back in. I told him I would at a later date since I needed it around the property. He was ok with that.

He doesn't know what is wrong with it, and I don't want to be without the tractor for a month or more again. Has anyone else experienced this issue? If so what fixed it?

Thanks!

Todd

 

[sweettractors]

I am not familiar with your model. Some tractors have a clutch brake that stops the pto when disengaged. Some movement after disengagement is pretty common on lots of tractors. Is the pto rotation at full torque or just slowly moving and could be stopped with a wood 2x2 rubbing against it lightly? Ken Sweet

 

[DAY]

What did they DO that cost $1600?

I agree with Ken; my ancient JD 850 (gear) has a PTO that always "idles"

 

[RoyJackson]

What did they DO that cost $1600?

I agree with Ken; my ancient JD 850 (gear) has a PTO that always "idles"

My 670 and 790 PTO's rotated too. Not sure about the 4400 (which would be closest to the 3520). I'll check that today.

 

[toddsuff]

It turns with a fair amount of Torque - but at a slower rate than the normal 540 RPM. Will try the 2x4 on it when I'm off work tommorow.

 

[Andrewnewy]

Don't stick anything in a PTO, except for a PTO shaft attached to an implement! Just do a search for arm lost by PTO to see how quickly they can rip your limbs off!!!

As for the problem, sound like a typical JD clutch problem, pretty common round our way, even had one where the clutch springs had exploded!
First thing to check though is if the clutch control mechanism has been set correctly, this is really no different to a normal clutch, if it's not disengaging the plates properly then it will slip and cause the PTO to spin, alternatively could be the clutch plates are worn common on old tractors, or PTO's that have been overloaded, once again fairly straight forward job, 8hrs to split the tractor, replace clutch and put back together.

If this has happened before, I'd be looking at what you are doing with it, and also making sure you have external slip clutches on your PTO implements, and that these clutches are set properly.

As for the dealer taking a month, unless he was waiting for parts to come in, should be no-reason for such a long delay!

 

[dmay]

A few troubleshooting questions:

1) From a cold start with PTO disengaged, is PTO stopped?
2) After tractor warms up does the PTO start to turn?
3) From a cold start with PTO disengaged, is PTO turning?
4) After tractor warms up does the PTO stop?
5) When PTO is disengaged but still turning, is the PTO torgue enough to turn a heavy implement or is it just enough torque to turn the unconnected PTO shaft?

 

[RoyJackson]

Don't stick anything in a PTO, except for a PTO shaft attached to an implement! Just do a search for arm lost by PTO to see how quickly they can rip your limbs off!!!

We have the tractor key in our pocket when hooking up that drive shaft.

You do make a good point that should always be adhered to...don't hook up the PTO drive shaft when the tractor is running. Keep that key in your pocket.
However, we were discussing rotating the stub shaft (on the tractor) a bit whie hooking up a drive shaft (which may require rotating the stub shaft slightly to align the splines) as well as the fact that some PTO stub shafts do rotate (with no torque) even when the PTO is disengaged.

 

[RoyJackson]

My 670 and 790 PTO's rotated too. Not sure about the 4400 (which would be closest to the 3520). I'll check that today.

Nope..my 4400 PTO stub shaft doesn't rotate...