Hydraulic leak problem JD 300 Industrial

[Tx Jim]

Here's a parts schematic of ind pressure control valve.

key 7 R28776 O-Ring - O-RING, PACKING ADD 1.40 USD
key 8 R60332 O-Ring - PACKING, O RING ADD 1.29 USD

 

[hamp34]

I am still looking for information on this problem. I can't be the only one to have this happen. Again: All seal have been replaced

 

[DannyWyatt]

I just purchased a JD 300 and I am having an issue with the reverser and the brake valve not working. Could this be caused by the pressure control valve, or do I have another type of headache?

 

[Tx Jim]

I just purchased a JD 300 and I am having an issue with the reverser and the brake valve not working. Could this be caused by the pressure control valve, or do I have another type of headache? [

Danny
Welcome to TBN
NO pressure control valve ensures oil pressure(1700 psi) for power steering from frt hyd pump but has nothing to do with reverser or brake valve as those functions are supplied by trans pump pressure(155-165 psi). You need to check hyd filter relief valve that's just in frt of hyd filter to be sure it's seating. How long since hyd filters were changed & sump screen has been checked/cleaned?

 

[DannyWyatt]

I can't really say, I sure it has been awhile. The tractor sat for 3 years with a bad motor and the older gentleman I bought it from had the engine re built. The issue was discovered after he had the engine installed. The rock shafts do not move either. The brakes feel like there is no fluid in them, the reverser will not move out of forward, however all the forward gears work fine

 

[Tx Jim]

1st thing to do is change hyd filters & clean sump screen. Hyd filers from JD are part number AR75603 & cost about $8 each. Rockshaft is supplied hyd oil via a galley in trans case which gets oil from pressure control valve. I'd suggest to check hyd stand-by pressure which should be 2250 psi. Reverser problem could be faulty control valve or control linkage problem possibly control valve.

 

[DannyWyatt]

Thank you TX Jim, I just got the tractor home Monday, but I have had to work until today. I drove the tractor about 1/4 mile and let it idle for some time. I pulled the transmission filter housing and found the fluid looks like gravy. I also pulled the plug out of the relief valve (which I don't believe has ever been out) and tried to pull the valve with my fingertip but I haven't had any luck. The tractor is away from my garage so I am walking back and forth for tools.

 

[DannyWyatt]

I have replaced the sump screen, changed the fluid, as well as a lot of hoses. I checked the pressure on the reverser and it was at 160 psi. I have been using the tractor for some time with no reverse or breaks. I finally got it in the garage. I pulled the top cove and checked the linkage to the reverser, all was good. The lever would not move. I pulled the master cylinder and reverser and found the control vale was stuck in the reverser body.
I let the assembly soak in pb blaster for a day and applied heat from a heat gun and freed the valve. I cleaned and polished the valve, but I can see a little pitting. I checked the diameter of the valve with mic and the is no variation. Should I replace the valve with a new one, or reuse the old one? ATTACH=CONFIG]543901[/ATTACH]

 

[wormmy4life]

I am still looking for information on this problem. I can't be the only one to have this happen. Again: All seal have been replaced

Were you ever able to find a solution to the leaking hydraulic casing? I have the same problem as you, replaced O rings didn't fix leak. Seems like it's leaking from the casing but I don't see a pin hole anywhere in the actual pressure control valve.