I’ve got a Komatsu PC220LC-6LE that the travel is weak ,all other functions operate as they should with sufficient power. The excavator will track straight both ways and the power is equal on both tracks it is just weak.I serviced it when I got it and the oil in both final drives was clean. I also don’t see a two speed travel switch anywhere. I did replace all of the hoses from the rotary manifold to the final drives and there no leaks anywhere. i would appreciate any suggestions on where to start the diagnosis of this problem.
Try and see if you can get a copy of the service manual for your machine and run through the cycle times, pressure stall tests and case leakage tests for the motors. Also check pilot primary and secondary pressures of the travel pedals if you have or are able to get pressure gauges and test fittings to do your tests. You may also need to check LS differential pressures when operating the travel motors. These procedures should all be outlined in the service literature if you can get your hands on a copy. Best regards
The problem is fixed, I decided after talking to my nephew who is a Deere mechanic to start with the rotary manifold. He and I pulled the manifold and upon disassembly found that the seals were non existent, the only thing left were a few bits resembling plastic crumbs. We reseal it and it now travels as it’s supposed to.