Wheel loader Komatsu WA200-1 transmission problem?

[makee]

Engine of the unit is running, only that it can't transmit power to the transmission causing the unit to be un-operational ..previous defect is that when in low gear unit is moving well but when changing to high gear unit is lacking of the desired force it should have produce. First thing we check is the control valve ass'y we pulled it out and overhauled it replacing gasket and o-ring..after refitting the control valve ass'y into the unit the problem become bigger theres no movement no forward or reverse..what we should do? your ideas and expertise can help a lot.. thank you and more power to everyone.

 

[DMiller]

You will need a service manual, then determine the hydraulics pressures feeding the system. If the pressures are not adequate start by inspection/replacement of filtration, if that has already been done then it could lead to lost seals in the system or a faulty supply pump. Without a service manual to check for specified or specific pressures and from where to check those you are chasing shadows where you could expend a great deal of time if not money before locating the exact issue.