John Deere 310A Pressure Control Valve

[MescalTerry]

I have a hydraulic leak from the Pressure Control Valve mounted on the right side of the transmission of my JD 310A Backhoe. I can find no procedure for removing this Pressure Control Valve in my manuals. Does anyone know if I can remove this valve without draining the transmission? It is extremely hard to get to from underneath or on top by removing a floor panel. It has 3 hydraulic hoses going to it of which two are steel, which makes it even tougher to disassemble. Any advice would be much appreciated!

 

[Tx Jim]

Welcome to TBN
To remove hyd pressure control valve one should drain hyd oil. You could remove hyd oil filler cap then place plastic sack snugly over opening to create a vacuum in order to slow oil draining down while valve is removed.

I've also read of inserting an operating vacuum cleaner hose in opening of hyd filler hole to slow oil draining time BUT if anyone chooses to do so PERFORM THIS TASK AT THEIR OWN RISK!!!

 

[MescalTerry]

Wow - Thanks. I got all 3 bolts out yesterday and it has been slowly dripping ever since, but now I will take your advice and drain the transmission using your plastic sack idea (which I really like, by the way). Would you possibly have any suggestions for getting the valve out of it's extremely tight confines?

 

[Tx Jim]

You're welcome.
Sorry but my JD utility tractor experience is limited to ag tractors not ind tractors. Most Ag tractor frt end loader frames were mid mount not back to rear axle housings like ind tractors.

 

[true temper]

Wow - Thanks. I got all 3 bolts out yesterday and it has been slowly dripping ever since, but now I will take your advice and drain the transmission using your plastic sack idea (which I really like, by the way). Would you possibly have any suggestions for getting the valve out of it's extremely tight confines?

Just get under it and do it. What problem are you having with your tractor. These rarely go bad.

 

[MescalTerry]

I had a fluid leak from under the Backhoe and saw that it was coming from between the transmission and the Pressure Control Valve (PCV). I drained the fluid and have now gotten the PCV out. They sure did not make it easy to get to it. The larger o-ring is brown in color and was definitely the source of the leak since it was not only flattened but was very brittle. It's probably the original and has never been changed (the backhoe is over 40 years old). After cleaning it up and looking it over I found that the flat surface of the PCV has a very slight bow to it so I am going to take it to a Machine Shop to have it milled back to flat. I found a new one in Canada for $2,300 for just the body so I'm going to rebuild this one and see how it goes. I have a cousin who used to be a John Deere mechanic and he said that he has used a file to flatten the surface, so that's plan B.
Thanks Tx Jim for letting me know that I had to drain the fluid before removing the PCV because I sure would have taken quite a bath had I not drained it.

 

[Tx Jim]

You're welcome. Now would be an excellent time to check/clean hyd oil suction screen. Please update us on your progress.