Peterson Pacific 4710B It has a track drive. The tracks are actuated by buttons on the control panel to allow a remote control, or levers on the Danfoss valves. The tracks were operational with both methods. One side started to remain moving after the button was released on the remote. I am not sure on the levers. It would continue for a second or so, then stop. After tracking for 100 yds or so, the one side stopped working. I determined that it goes fine in one direction, but nothing in the other direction, by either of the actuation methods. Now, when I turn on the track drive activation (safety button?) the one side starts tracking even though there is no input from the remote or the valve lever. I unplugged the solenoid, no change. I replaced the solenoid with a new one, no change. I removed the valve, disassembled, inspected, and reinstalled it, no change. Everything looked good inside it though I am no valve expert. What could be wrong? Is there something in the hydraulic track motor I can/should check? Any ideas on testing procedures? TIA for any help you can provide.
I have not crawled all the way under this machine yet to physically trace hyd lines. Am I right to think those hyd lines in the valve the only hyd flow going to the track motor(s)? If so, with the solenoid unplugged, there could be no computer/electronic control affecting things. That would leave the valve and the track motor as the only possible things that could be bad/broken. Thoughts on this?
Are there brakes on the motors ?
The track drives on a Peterson Pacific 4710B horizontal grinder use integrated internal spring-applied, hydraulically released parking brakes built directly into the track drive motors/gearboxes Release: When you activate the track drive using the control panel buttons, radio remote control, or manual levers, pilot hydraulic pressure automatically flows into the brake release port on each track motor to compress the internal springs and free the drive. That is something I can check into. I know nothing about these systems, so this is good info for me, thanks! I don't know the things that I don't know to research.
There generally are safety systems in the machine that prevent movement in certain situations, likely while the rotor is turning. Check all the wiring that you find hooked to fittings with pump pressure on them. Travel motors generally don't use pilot pressure to release the brakes. All that I know of use main pressure to turn the motor itself. Pilot pressure is used to shift the motor between high and low speeds.
John, I've had experience were there were 2 pilot lines on the travel motors, 1 for the 2 speed and the other for the breaks. That was on Nabtesco motors and activated by the safety features in the cab. Even unloading off a truck that machine would move on it's own.
This problem occurred as I was tracking the machine to load it on a trailer. I was using the remote control. It was going to a Peterson Pacific dealer service center for some repair work. I called them at the time and they told me which valves to use to manually track the machine. I found this today. Apparently one of the valves they told me to use was not for the 2nd track motor. I replaced that solenoid and removed, disassembled and reinstalled the wrong valve. When back at the machine I will go to the correct valve and work it manually. It may free up something and allow the remote to work properly again or at least I can track it manually. I won't be tracking it on a trailer to send to them though. Red is actual track valves. Blue is the one I worked on because they told me it was for the 2nd track.