john deere 3325 winch

[timberhog]

    I have a 3325 winch on my 550 dozer and it works good for about the first hour and then the more I use it the more rpm's I have to give it to release the cable. I have rebuilt the releaf valve and all the lines in the winch. So now what do I look for ?

[snowstorm]

have you changed the filter? have seem them with enought water in the oil to freeze in cold weather. low oil pressure. or if its not used much could be a little rust on the clutch discs. pull them out an clean them wire brush sandpaper

[tjdub]

There's an intake screen tube that bolts directly into the on the bottom of the hydraulic pump.  Drain the fluid and pull the plate off of the bottom right side of the winch and it's right there.   Take it out and wash  it up with some gasoline.  You'll probably find that it's plugged up with sludge/snot.  Changing the filter is a good idea, but it's probably not the cause of the pressure problem since it's on the return-side.

There's a non-adjustable 1000psi relief valve built into the pump as well, but if it's a pressure problem (and it sounds like it) it is most likely with the intake screen or the pump is worn out.  I cleaned my intake screen up and it was obviously plugged.  Filled it back up with fluid and saw no improvement so I pulled the plate off again to pull the pump out and the screen was plugged AGAIN.  Cleaned it out a second time and it's been working perfectly ever since.

As snowstorm said, it might be a problem with the clutch.  You can verify this by putting  a pressure gauge on the test port on the top left side of the winch.  It should read 1000psi when in free-spool or wind mode, and 0 otherwise.  If your pressure is good, you know there's a problem with the clutch.  It's also possible that when you rebuild the external relieve valve you didn't get it adjusted high enough, with a gauge on it you can try turning it up to see if it helps.

[timberhog]

    I have put a pressure gauge on it and it starts out fine but when it warms up the pressure drops and I have put on a new pump and screen as well . The screen looks clean when I drop the plate. Maybe I got a bad pump I will pull one from the skidder and try that one to see if that is it.

[snowstorm]

was the pump new or used?? if it was used when the oil gets hot it can slip by and that makes it get even hotter

[timberhog]

The pump was new when I put it in and that didn't help eather.

[snowstorm]

dose the shaft on the new pump turn by hand easy? it shouldnt should turn but a bit hard

[timberhog]

  It kind of turns alittle hard I would say.

[snowstorm]

ok good then the pump should make pressure. you have a gauge check press again do you hear a squeal? like releif? check for dirt in relief holding it open broken spring. did it have plenty of power winching in?? pull out hard?? clutch discs can cause that they drag steel between fiber. or if when released it tries to winde in just a little

[timberhog]

 It winches in fine it is just the free spool I have trouble with.  It will get progressively harder to pull out and the pressure drops alittle every time. I'm affraid to turn the releaf valve in too much and brake the pump with too much pressure.

[doghunter]

does it try to wind in in free spool ?if so rings on clutch piston bad .also an internal line leak is possible

[doghunter]

put test gauge in brake release test port when hot should check same as main port if not control valve problem

[timberhog]

Ok I will try that tomarrow thank you . And no it does not wind  when in free spool and all the lines have been replaced.

[tjdub]

You don't have to worry about breaking the pump by turning up the relief valve too tight.   The 1000psi relief valve built into the pump keeps the maximum pressure of the system at 1000psi or less.  Most of the external relief valves on these winches are turned up too high from people "debugging" and then forgetting to turn them back down with a gauge, but it really doesn't hurt anything (unless the one on the pump would plug up and fail, I suppose).

Assuming you've had the side cover off and didn't find the brake piston leaking, I think it points at a leak inside the rotary spool valve.   It's kind of hard to reach, but you can take that spool valve off and inspect the brass guides for scoring.   Careful because the only thing holding it together are the same bolts that hold it to the winch.   Also, pay attention to which parts came out of which hole because if mix up the inserts in it will go together fine, but not function (learned that one the hard way ).  Deere sells the seal kit for $115 that (I think) includes all of the brass wear parts for rebuilding the control valve.  You can buy the brass parts individually too if there's just a problem with the one that runs the brake piston.  Also, if you find there's a problem with just the brass part for the brake circuit, you can swap it with the one for the clutch circuit since you probably aren't doing much winching at low RPMs and could stand a little leaking on that one.

[timberhog]

    Thanks I will look at that too. And yes I have been in the whole thing and not found any leaks.The only leak I found was a seal on the wet side and that has been replaced and new cluch plates are in and a new brake band in it as well.