Transmission oil pump 20/925552 JCB, genuine

For the JCB machines: transmission oil pump 20/925552, a genuine JCB part.

The pump is chosen by gearbox type and part number, as the flow, drive hub and connections can differ between versions of the transmission, so the old and new numbers on the card are taken into account. When the pump is changed, the torque converter hub that drives it is inspected too, since a worn hub soon ruins the drive of a new pump. After a pump failure, the transmission oil and filter are always renewed, because wear debris may have been carried to the clutch packs and valves. Pump pressure is measured with both cold and hot oil; a big difference between them indicates internal leakage. When a pump fails, remember that the clutch plates may also have overheated, and open and inspect the packs if needed.

Specifications

Compatibility

According to the product card, 20/925552 is a transmission oil pump. The card also lists 20/925466, 20/925335, which are other JCB numbers for the same part. Fit is confirmed by the part number. The catalogue also has the aftermarket version of this part. Other parts are in Transmission.

Fitting

The pump is removed by separating the gearbox from the engine or opening the gearbox cover; clean the mating faces and use a new gasket or O-ring. Align the pump drive with the converter hub and tighten the bolts in a cross pattern to the specified torque. After assembly, top up the transmission oil, run the engine at idle to let the pump prime, then measure the line and clutch pressures with a gauge. Check for leaks and unusual noise.