W 250 Pickup V8-5.9L VIN Z (1991)
REPAIR
The air injection pump is a non-repairable unit, the only serviceable part is the centrifugal filter fan. Do not disassemble or attempt to rebuild the pump
for any reason. If the pump has been found to be faulty, replace the whole unit.
REMOVAL
1.
Remove air hose from switch/relief or diverter valve.
2.
Loosen air pump pivot and adjusting bolts, and remove air pump belt.
3.
Remove air pump bolts. Remove air pump and pulley, switch/relief or diverter valve, and brackets from vehicle.
4.
Remove switch/relief or diverter valve, brackets, and pulley from air pump. Remove the gasket and clean surfaces that will be used again.
INSTALLATION
1.
Install air pump pulley, diverter or switch/relief valve (use new gasket), and brackets on air pump. Refer to SPECIFICATIONS for torque
specifications.
2.
Position air pump on engine and install pump bolts and pump pivot bracket.
3.
Install air pump belt and adjust to specifications. Refer to SPECIFICATIONS for air pump belt and mounting bolt torque specifications.
4.
Reconnect air hose to the switch/relief or diverter valve.
WARNING: Never pry on the air pump housing to tighten the drive belt.
Removing Centrifugal Filter Fan
CENTRIFUGAL FILTER FAN
REMOVAL
1.
Loosen air pump adjustment bolt and remove drive belt.
2.
Remove air pump pulley bolts and remove air pump pulley.
3.
Insert a pair of needle nose pliers between the plastic filter fins and break the assembly from the hub. Be sure that no fragments fall into the
air pump inlet.
NOTE:
Do not try to remove the hub from the air pump, and do not pry between the filter fan and the air pump housing.
