farmmaterialmover
Member
The thumb has been working correctly but then quit while running it. It will now squeeze somewhat, but it will not raise up out of the way on its own. If you turn the thumb off, it will settle to the squeeze position almost immediately. I know the thumb circuit is somewhat complex on these machines. First thought would be we blew the plunger seals out of the thumb cylinder. Any other common mishaps with other valves or should we start with cylinder first? After it quit, we had it chained up out of the way, but the operator accidently engaged the thumb and it broke the chain....so it has a bit of force down but won't lift its own weight going up. That also has us questioning whether the cylinder is actually the problem. We have 3 positions to run the thumb hydraulics. We have been running it on thumb. When it quit, we tried hammer and shear also and that didn't help.