I recently purchase a used 2001 Komatsu PC40 MR-1 (MRX-1) and it is only going to be used as a farm machine.
The machine initially runs really well and all functions are in line with expectations for a 19 year old machine.
However after using the machine for around 10 minutes, the boom, arm and bucket hydraulics slow dramatically. Temps are fine, engine is still humming along and nothing else seems to be wrong, however as an example it may take 15-20 seconds for the arm to go from fully extended to fully retracted.
I don't expect miracles from an old machine, but the speed is acceptable when I start using it and power seems fine. If I refer to the service manual and check the expected speed of each of the functions, it should take only 4 seconds to fully extend or fully retract at full engine revs. As its an older machine this may be 4.5 seconds on initial use, but certainly nothing to complain about.
But all of a sudden the speed drops way down and waiting 15-20 seconds for a boom or arm to extend/retract is a real issue.
If I stop the machine and check levels and temps everything is OK. If I leave it for 20 minutes and start it up again, the speed is back to normal but it will slow again after the same period of time.
There are a few small leaks in the hoses which I am getting repaired. For example, the bucket extension hose drips about 2-3 drips a minute under load, but hydraulic oil levels are still well within tolerance. Could this be causing a depressurisation and subsequent speed loss?
Could it be overheating the hydraulic oil?
Could there be a blockage in the supply/return lines?
I have already replaced the Hydraulic and Power line Filter and plan to replace the strainer next.
Any other ideas from the brains trust?
The machine initially runs really well and all functions are in line with expectations for a 19 year old machine.
However after using the machine for around 10 minutes, the boom, arm and bucket hydraulics slow dramatically. Temps are fine, engine is still humming along and nothing else seems to be wrong, however as an example it may take 15-20 seconds for the arm to go from fully extended to fully retracted.
I don't expect miracles from an old machine, but the speed is acceptable when I start using it and power seems fine. If I refer to the service manual and check the expected speed of each of the functions, it should take only 4 seconds to fully extend or fully retract at full engine revs. As its an older machine this may be 4.5 seconds on initial use, but certainly nothing to complain about.
But all of a sudden the speed drops way down and waiting 15-20 seconds for a boom or arm to extend/retract is a real issue.
If I stop the machine and check levels and temps everything is OK. If I leave it for 20 minutes and start it up again, the speed is back to normal but it will slow again after the same period of time.
There are a few small leaks in the hoses which I am getting repaired. For example, the bucket extension hose drips about 2-3 drips a minute under load, but hydraulic oil levels are still well within tolerance. Could this be causing a depressurisation and subsequent speed loss?
Could it be overheating the hydraulic oil?
Could there be a blockage in the supply/return lines?
I have already replaced the Hydraulic and Power line Filter and plan to replace the strainer next.
Any other ideas from the brains trust?
