I have an older case 850 dozer and it has been working fine until last week. i have no lift on blade or angle but it has a quick coupler hookup on the back of dozer.the hoses are connected and when i disconnect them the blade will work but the pump loads the engine and it won't rev up. if i put the rear hoses back together the motor revs up fine but the blade will not raise.I removed the main relive valve and it looks fine.I would appreciate any help trouble shooting the problem
What is the routing. One or two section pump that runs to a multi section valve first or the quick coupler or
Be careful you don't dead head the pump or you'll destroy it in short order. I wouldn't operate it with the quick couplers disconnected if it used to run fine and this is a new problem. What shape are the quick couplers in? If they are worn and not letting full flow or not fully connected can cause problems. How the hoses are routed would help to diagnose the problem. What were the quick couplers for, a ripper or backhoe?
850 case hyd problem the hoses from the quick coupler, one goes to a block coupler the other goes to the main valve bank that operates the blade.It has a hose comming from the pump to the quick coupler block and from there to the valve bank.I don't have a manual to see how the hyd system works. there is a lot of hoses and block connectors. I think it has a relive valve stuck open somewhere but the one i checked on the main control valve is ok.The dozer was working fine when i last used it but when i started it up this time the blade wont raise, it will try to move a little but doesn't have any power.I put it in heated shop to be sure it wasn't froze but that's not a problem.The oil to the blade control is bypassing somewhere but where i don't know where
850 case dozer hyd problems I finally found my problem and will share what it was incase someone has the same problem.as i said in a previous post the blade stopped working.the dozer has a backhoe option for the back and has a valve that is located under the foot peddle that puts oil flow to either the backhoe or the blade. It is a small lever and was easy to miss. Thanks for the reply from members.This is a good site