Hydraulic leak problem JD 300 Industrial

[hamp34]

Hi All

I have a leak coming from what I think is the pressure control valve located on the side of the tractor- under the foot rest- above the filter.

I watched a video on youtub on this and it was the fitting going into the valve. The leak is coming out of what looks like the side of the valve- not the fitting
I have look for this problem on the threads here however can't find it. The tractor has a back hoe and loader

 

[RLstangs]

There is black o-ring that fails behind that valve. It has been changed to a harder white o-ring that lasts longer. There is also a change to the housing with a screw in adapter fitting that screws into the transmission housing if the heavier o-ring does not fix it. It is the hydraulic pressure control valve on jdparts.
http://jdpc.deere.com/pimages/TP55/thumbs/TP5587_________UN01JAN94.png

 

[hamp34]

Thank you for your response. Why does it look like the leak is coming from the back side of the valve and running onto the fitting?

It looks like there is some sort of pin hole in that valve or is that just how it shows up with the bad seals?

 

[RLstangs]

The oil pressure comes into the valve on the back side from the transmission housing. That is where the leaking o-ring is.

 

[Tx Jim]

The oil pressure comes into the valve on the back side from the transmission housing. That is where the leaking o-ring is.

Correction pressure doesn't originate from trans housing: hyd oil pressure comes down line from frt hyd pump to pressure control valve then goes to hole in trans case that leads to rockshaft control valve. If tractor ise quipped with scv &/or loader then they get pressure out the rear of priority valve

 

[RLstangs]

Yea worked 16 hours yesterday, just trying to say there is oil pressure going out the valve on the back side to the trans case.

 

[hamp34]

All of the seals / o-rings have been replaced and I still have the same leak it seems like their is some sort of pin hole in the casting on the back side I cleaned it and could not find anything that looked like a problem / crack / pinhole

 

[RLstangs]

Solution Summary: Pressure Control Valve Housing Groove for Sealing Ring Missing

Publication Date: Mar 24 2003

**Paper copies of solutions may not be the most current solutions**

Problem:

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Attempting to replace pressure control valve. Original housing has groove cut into housing for sealing ring part number R60332, new housing, part number R66083 does not have groove cut in it for sealing ring, customer afraid will leak oil.

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Solution:

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The pressure control valve assembly uses a flat packing in the shallow counter bore on the milled surface at the rear of the valve. The hsg has a deeper counter bore toward the front hsg.. This deeper counter bore mates up with a special fitting that requires an o-ring and is screwed into the transmission case (by means of an internal hex). On this special fitting there is a groove where a backup ring and a o-ring need to be installed. The hsg. is installed to transmission case in such a way as to position counter bore in the hsg. over the special fitting installed in the transmission case and to align the three holes on the trans. case. The o-ring / backup ring provides the seal in the hsg. at the front and the flat packing provides the seal at the rear.

 

[RLstangs]

If there is a threaded hole in the transmission housing you can install the new style valve and threaded adapter to stop the leak. Numbers 12 - 15 are the adapter and the housing is number 6. Install the parts from the old housing into the new housing. I looked up the parts for my 2440, I have installed the new parts on my 2440 and it stopped the leak. Double check the parts are the same on your tractor.

 

[RLstangs]

Looked at your pictures, industrial tractor pressure control is different. Would have to check with industrial dealer.