I have a 2005 Komatsu D31PX -21A. The machine tracks won't turn forward or backward under 1200rpm. After all our testing we found out that the control valve for left and right track won't release the valve if the engine is under 1200rpm. Which means the control won't get any signal 1200rpm for releasing the valve. i'm not sure what is the problem. The hydraulic pressure is normal. Any one can help or suggestion?
Is this machine hydraulically piloted or completely eletrical? If the engine has to be spun faster says there is a flow problem. What is the pilot pressure at idle compared to 1200 rpm? Standby -idle and 1200? Applied - idle and 1200?
It has a dual-path hydrostatic transmission. The following table tell you everything we have tested. Pressure RPM Voltage(Left Control Valve) Voltage(Right Control Valve) Tracks reaction 35 780 0.02 0.02 Not Running 38 1117 0.02 0.02 Not Running 28 1177 3.28 3.57 Running slow 28 1239 3.5 3.8 Faster Abnormal between 28 to 35 1532 5.08 5.05 Faster 28 1734 6.3 6.32 very fast
dash 21 dozers have a piggy back HST pump set up.....two drive motors and no transmission.....sounds like the AS valve may have an issue what is the serial # and is it a KOM 1 or KOM2?
The s/n is 50817. Not sure about KOM 1 or KOM 2. Can you tell by the s/n? Please advice what kind of troubleshoot I should go for? Thanks.