R190 leaking from both wheel motor brake covers.

[dfl3006]

We have an R190 leaking oil from the brake covers(Poclain single speed) when the park brake is taken off. It uses pilot oil. Only needs a max. of 435 psi to release the brakes. I'm still looking for the right adapter to test the pressure and what the pressure should be. Any ideas? I can't imagine both seals on a 6 year old machine with no other problems would fail at the same time. But it does have 3800 hours on it.

 

[walio123]

It is quite possible for two brakes to leak at the same time. Almost always happens or they leak one after another in a short time. However, checking the pilot pressure is a good idea. I can not remember exactly how it should be, I think the minimum is 25 bar maximum 40 bars. 345psi may be the correct information (30 bar). I can check tomorrow if necessary.

 

[dfl3006]

It is quite possible for two brakes to leak at the same time. Almost always happens or they leak one after another in a short time. However, checking the pilot pressure is a good idea. I can not remember exactly how it should be, I think the minimum is 25 bar maximum 40 bars. 345psi may be the correct information (30 bar). I can check tomorrow if necessary.

Thank you. I was able to find a service manual. 30 bar/435 psi for this one. Now for the adapter.Deere had a similar issue on a few models when the case drain filter clogged. They hid that thing well. I hoped maybe Gehl had a similar common cause.

 

[walio123]

Thank you. I was able to find a service manual. 30 bar/435 psi for this one. Now for the adapter.Deere had a similar issue on a few models when the case drain filter clogged. They hid that thing well. I hoped maybe Gehl had a similar common cause.

When case drain filter is clogged usualy a hydraulic motor leaking fom shaft seal, and leaking is high. There must st be 2 case drain filters /for each motor/.

 

[dfl3006]

When case drain filter is clogged usualy a hydraulic motor leaking fom shaft seal, and leaking is high. There must st be 2 case drain filters /for each motor/.

That was what the Deere did. Sometimes one. Often because the motor was failing. Sometimes the new motor was installed without changing the filter. The Gehl shows the brakes are spring actuated and are released by a solenoid controlled valve using pilot oil. It only leaks when the park brake is released. If the pressure is too high I need to find the source.

 

[dfl3006]

That was what the Deere did. Sometimes one. Often because the motor was failing. Sometimes the new motor was installed without changing the filter. The Gehl shows the brakes are spring actuated and are released by a solenoid controlled valve using pilot oil. It only leaks when the park brake is released. If the pressure is too high I need to find the source.

Sometimes one meant only one leaking. Two filters. Old dirty oil and abuse usually plugged both before they noticed the problem.

 

[walio123]

Thank you. I was able to find a service manual. 30 bar/435 psi for this one. Now for the adapter.Deere had a similar issue on a few models when the case drain filter clogged. They hid that thing well. I hoped maybe Gehl had a similar common cause.

There must be a regulated relief valve on the solenoid valve for the brake,There is two models , one is regulated by screw, the other with washers between the housing and the spring.Any "Tee " with male/female 2 ports with brake hose thread dimensions ant third port for pressure gauge will work.

 

[dfl3006]

There must be a regulated relief valve on the solenoid valve for the brake,There is two models , one is regulated by screw, the other with washers between the housing and the spring.Any "Tee " with male/female 2 ports with brake hose thread dimensions ant third port for pressure gauge will work.

Finally found enough fittings to make it work. Tested 500 psi at idle and 550 psi WOT. Doesn't sound like much but that's 15-25%. The line comes straight off the charge pump, tees off to a few other solenoid valves, then through the park brake solenoid valve to the brakes on the motors. I'm thinking if system pressure tests low(need to check that next) it may be an internal leak? It shows a relief valve that may have shims that could be removed at the charge pump. If there's an adjustment at the brake solenoid valve I guess I need to test pressure between the solenoid valve and the brakes?

 

[walio123]

Finally found enough fittings to make it work. Tested 500 psi at idle and 550 psi WOT. Doesn't sound like much but that's 15-25%. The line comes straight off the charge pump, tees off to a few other solenoid valves, then through the park brake solenoid valve to the brakes on the motors. I'm thinking if system pressure tests low(need to check that next) it may be an internal leak? It shows a relief valve that may have shims that could be removed at the charge pump. If there's an adjustment at the brake solenoid valve I guess I need to test pressure between the solenoid valve and the brakes?

I hardly do not believe that the factory setting of the pressure is not accurate. It is possible to have trash in the relief valve and it does not work properly. Otherwise, your idea is good, but I think there can be no internal leakage. If it is, the pressure should be much higher. at least 150 bars /2175psi/ Оtherwise you are right, you have to pull out a piece of the washers if pressure is high, or if one washer is, put on a thin one.