Gehl V330 won't steer after running for a few minutes. When Started, it works great.

[Hnowak]

I have a GEHL V330, and everything works fine for a few minutes. You can turn in either direction, drive forward or reverse; boom works in all directions. After a few minutes, the boom becomes very slow, and the machine will not turn at all. If you adjust the engine RPM, you can get it to turn slowly and go forward just fine, but the boom is still very slow. I changed the coils and repaired all electrical problems. Any idea how to find what changes after 5 minutes of operation to cause these problems? Only seems to happen when hyd oil is cold. Once it warms up, problems begin.

 

[brdgbldr]

Could be your pumps are warn out.

The other cheaper issue is that you are running too thin of an oil. The oil is heavier weight when cold and as it warms up it gets lighter/ thinner and the pump can't make enough pressure.

 

[Firefighter]

Sounds like its loosing charge pressure, i would test pressure to see if it drops, if its all joystick controlled the pressure should be around 435 psi at operating temp

 

[Hnowak]

I found the charge psi drops off when it fails. I removed the solenoid and found it slipping in the housing. Put a new one in and ran it. It ran for 15 minutes, did the same thing. This time it immediately, fixes itself after a restart, then runs again for 10 minutes or so—same thing.

I replaced the oil, no change.

 

[ward]

All of the skid steers I worked on had a valve at the hydraulic filter controling the charge pressure or what is also known as makeup oil at the hydraulic filter, I guess you could have a valve in the system that removes pilot pressure for saftey, I would be looking at the seales on the valve as I have seen hydraulic systems that have seals fail, also if the valve has trash in it it could get stuck open causing the same issue.

 

[Firefighter]

possibly the solenoid valve block itself, or the charge pump, or worn internal hydro pump parts. what is the actual pressure that u have? if it is an all joystick loader u should have around 435psi at hi idle, the charge pump is part of the front hydro pump assembly w/ a relief valve

 

[Hnowak]

All of the skid steers I worked on had a valve at the hydraulic filter controling the charge pressure or what is also known as makeup oil at the hydraulic filter, I guess you could have a valve in the system that removes pilot pressure for saftey, I would be looking at the seales on the valve as I have seen hydraulic systems that have seals fail, also if the valve has trash in it it could get stuck open causing the same issue.

Where would this valve be located? There is nothing on the filter itself or any additional lines coming off from it.

 

[Hnowak]

You are correct. There is no actual charge pump. The charge is sourced from the control valve and the hydro pump. I will check the block and see if there's trash or something.

I don't recall the psi, but it was high enough that I was not concerned. I think I had a 600 psi gauge on it, and it was above 400.

 

[ward]

I have not worked on that model skid steer, however if you go from the controls back tracking following the supply line to the controls you should find a valve that is also down stream from the filter (I am gessing), I had done some research and found an online parts manual for the model you listed( did not have the serial number to see if it was in the same group) and the filter housing does NOT show a relife valve on it, there was a valve block that looked like it might be a lock out valve.
You had said that you took the solenoid off in pervious post, I am wondering if you only took the coil off and did not pull the cartridge under it and checked the o rings seals on the cartridge, that said I did not see any parts listed other then the valve block, however sometimes the part number of the valve has its own listing and break down in the parts manual.

 

[Hnowak]

I have not worked on that model skid steer, however if you go from the controls back tracking following the supply line to the controls you should find a valve that is also down stream from the filter (I am gessing), I had done some research and found an online parts manual for the model you listed( did not have the serial number to see if it was in the same group) and the filter housing does NOT show a relife valve on it, there was a valve block that looked like it might be a lock out valve.
You had said that you took the solenoid off in pervious post, I am wondering if you only took the coil off and did not pull the cartridge under it and checked the o rings seals on the cartridge, that said I did not see any parts listed other then the valve block, however sometimes the part number of the valve has its own listing and break down in the parts manual.

I replaced the whole cartridge. I have the manuals for this unit. The original cartridge was moving inside the housing about 1/8 of an inch. I thought that was it, but it just runs longer before failure. I will be fully focused on it tomorrow and look for any valves I may have missed.

 

[ward]

I am going to guess that the block the valve was in is aluminum and if the unit was running with the cartridge lose then I would be concerned that the tolerance is out of wack and you need a new block as aluminum can have a lot of wear with the cartridge lose.
That said I would also check the block to see if it is warmer then the surrounding valves as a abnormal leak can generate heat of about 20 degrees above the rest of the system, this is a way to find leaking dual hydraulic cylinders when one loses its seal internaly the leaker will run about 20 degrees warmer.

 

[Hnowak]

I connected the gauges again and ran it all over the yard. I discovered that this failure occurs when I make a hard right turn. I went left so many times I got dizzy. When you turn hard right within seconds, it fails. A slow turn while moving right takes more time to fail. I think the psi relief for the right wheel pump, not the drive motor, may be set to weak.