My early model 2010 Wheel (industrial backhoe) has had a variety of over-pressure problems ever since i ended up with it: leaks, blown seals, banging in the lines, etc. It's an H-L-R transmission with power steering.
I teed in a pressure gauge at the output of the cooler, and found that once you raise the RPMs, the pressure on the drain line jumps to about 10-15psi and the lower seal on the steering pinion begins to drip (wheel not being turned).
I started in with the tests described in the manual, and found a steady 120 psi at the accumulator test port, slightly above the spec. However, when I performed the relief valve test (plug the cooler inlet with a gauge), i measured the expected ~45psi at slow idle, but things got wonky as soon as I throttled up. The gauge would start bouncing between about 20 and 60 for several seconds before settling around ~30. The supply line to the filter/regulator assembly also started banging pretty bad.
All the lines are clear and free of kinks, so the only thing I can imagine is too much fluid coming from the external hydraulic pump via the power steering. As I understand it, the external pump runs only the steering, with the remote bypassed under the steering column and the rockshaft line draining back internally (and the shifting itself driven by a separate pump integrated with the driveshaft). There are mentions of an internal divider valve, but not much information about it. If it were to be malfunctioning, could it send all 11gpm to the power steering (instead of the 4gpm the manual implies) and cause backpressure in the rest of the system? Is there any way to test it short of just routing it into a bucket and measuring? Any other ideas on what might cause this behavior?
Thanks
-sb
I teed in a pressure gauge at the output of the cooler, and found that once you raise the RPMs, the pressure on the drain line jumps to about 10-15psi and the lower seal on the steering pinion begins to drip (wheel not being turned).
I started in with the tests described in the manual, and found a steady 120 psi at the accumulator test port, slightly above the spec. However, when I performed the relief valve test (plug the cooler inlet with a gauge), i measured the expected ~45psi at slow idle, but things got wonky as soon as I throttled up. The gauge would start bouncing between about 20 and 60 for several seconds before settling around ~30. The supply line to the filter/regulator assembly also started banging pretty bad.
All the lines are clear and free of kinks, so the only thing I can imagine is too much fluid coming from the external hydraulic pump via the power steering. As I understand it, the external pump runs only the steering, with the remote bypassed under the steering column and the rockshaft line draining back internally (and the shifting itself driven by a separate pump integrated with the driveshaft). There are mentions of an internal divider valve, but not much information about it. If it were to be malfunctioning, could it send all 11gpm to the power steering (instead of the 4gpm the manual implies) and cause backpressure in the rest of the system? Is there any way to test it short of just routing it into a bucket and measuring? Any other ideas on what might cause this behavior?
Thanks
-sb