H0004 Procedure for Changing the Hydraulic Pump on MK4 and MK5 Sidelifters

1. Disconnect the battery.
2. Close the oil tank isolating valves.
3. Disconnect the low and high pressure hoses from the pump (cap hoses).
4. Remove the bolts securing the pump mounting plate to the bell housing and withdraw the pump. Remove the male drive coupling and plate assembly.
5. Inspect both the engine and pump drive couplings and the plastic sleeve for signs of wear, replace parts as required.
6. Fit up pump to its mounting plate, fit the drive coupling to the pump shaft using new key tab washer and nut, torque the nut to 40Nm (30 ftIbs) and lock the tab washer.
7. Fit the plastic sleeve and mount pump assembly to the bell housing.
8. Carry out oil change or establish oil quality (change oil if necessary) and fit new low pressure oil filter.
9. Connect low and high pressure hoses and TURN ON OIL TANK ISOLATING VALVES. Top up oil level as required.

Commissioning pump

1. Back off the main relief valve adjustment on both Cassappa control valves by two full turns of the adjustment screw. Refer 2 below.

   

2. Reconnect the battery and start the engine. Allow the engine to run for a few minutes to circulate oil through the system.
3. To set the relief valves it is advisable to connect an accurate oil pressure gauge in place of the existing Sidelifter gauges.
4. Starting with rear crane, lower the top arm to the end of its stroke and read the pressure while holding the control lever down. Once a steady reading is observed small adjustments can be made to the relief valve to obtain a reading of 4000 PSI (275 Bar). Secure the adjustment locking nut and recheck the pressure. Carry out the same procedure for the front crane.
5. Check hoses and fittings for leaks; check pump and bell housing mounting bolts are secure.