Cat D6H Dozer transmission scavenge pump seizure. The torque converter has been serviced and pressure testing results were: Torque converter inlet 90psi, P1 .......360psi P2........300psi P3.........30psi The system has been serviced and the machine sent to site. The machine has failed pump again. Proposing to extensive pressure testing at stall and oil outflowing during transmission loading. Suspect the cause be faulty priority valve. Could this be the cause?
Hy, I know the D5H system, beeing a modular design as the 4 and 6´s of the era, shouldn´t be diff though except where it has to. Usually the Trans do not has scavenge, the TC yes, but if it fails the oil will overflow out throug the breeder. Usually one measure TC outlet press, this line goes to cooler. And from a diff oil circuit. The priority valve prioritizes pressure to braking and clutching, only when this needs are satisfied one has press to use the GB. Anyway, u´d better get hold of a test sheet for that machine, and menwile post the causes that let u to suspect the trans pump being damaged.
My experience with pumps burning up after installation usually involves someone leaving a rag or debris in the suction side of the pump.
I'm old school so may not apply on this new stuff but the old common cause was matching a new pump/splines with old spline drive. Results in an interference fit where the wear pattern exists on the spline. Old time fix was to cut about 1/8" off the new male spline so there is no interference, or replace the drive spline item when replacing the pump. Many a new pump has been ruined by not considering matching the splines which jams the drive gear against the pump housing.
O.M. not the same type of pump set-up on the D6H. tctractors
Kind of knew I was out dated, thanks tc