Good morning, I just purchased a Komatsu D37PX-22 from the "not working" line at the auction. Very good condition, 3300 hours. Engine runs great, 6 way blade works great, hydraulic fan works. Dozer did nothing at all in any gear or direction. I took off the floor plate to get a look at the Hydrostatic pump and noticed a 1 1/2 inch hose ( took a 1 3/8 wrench) was undone and capped off. This came out of the top on the pump and angled back to the left side rear of the machine. The book called this hose the "charge port CPR hose". I took the cap off and installed the hose back to the pump. I also went under the machine and adjusted the valves back out of "tow mode". When I started the dozer up the right track went into reverse and stayed there. Didn't matter what direction shifter indicator was in including neutral - only went in right track reverse very strong. Only way to stop was to apply brakes. The service book gives possible fixes for different issues or even combos of issues but not on reverse right. My guess is that the Hydro pump is bad but I do not want to take it out if it could be something different especially since the cab would need to come off. Also, if it is this pump, is it replace only or rebuild. I'm new at the HST pumps, any help would be appreciated, Thank you , Trip.
The machine is probably a little newer than most around here have experience with. I do not know the drive or steering system on one of these but hopefully someone will be along that can provide some insight. My thoughts at this point is that something bad has happened and it was determined it was more expensive to repair than the machine was worth. I would suggest pulling any hydraulic and transmission filters and check for dirt and metal debris. That might make it a little easier to start tearing things apart in the near future.
May be as simple as the cradle bearing came apart