Hydraulic pump 79932850 Terex/MST, aftermarket

For the Terex and MST backhoe loaders: hydraulic pump 79932850, an aftermarket part. The card also lists 5424100.

The pump directly sets the machine's digging performance and cycle times, so pressures and flows are measured before replacement to confirm the pump is at fault. An air leak on the suction side causes cavitation, noise and pitting of the gears. The pump body is cast iron, and the flange seals and suction hose clamps are renewed during the swap. Keeping to the oil and filter service intervals is the most important condition for pump life. This pump is the other option for the same part number, with the same displacement, shaft, flange and port layout. Backhoe loader pumps look alike, but rotation, shaft type and port threads differ with the machine make and model, so the pump is chosen by part number and checked against the old pump's label. Check the drive coupling and shaft seal during the swap. The pump is supplied new with its ports capped. The pump is heavy. The ports are capped.

Specifications

Compatibility

The product card gives the pump displacement as 41/29 cm³/rev. The catalogue also has the OEM version of this part. Other parts are in Hydraulic pumps.

Fitting

Before the change, drain and clean the tank and renew the suction strainer and filters. Fit the new pump with the shaft and coupling cleaned and new flange seals. Fill the pump with clean oil before starting, run at idle to purge air and check the pressures.