ELECTRICAL AR 3535028 - Caterpillar

2. Remove inlet tube (1) and outlet hose (3) from hoist pump (4).3. Remove two bolts (2) that fasten hoist pump (4) to the pump drive, and remove the pump.4. Inspect the condition of all O-ring seals, and make replacements if necessary. The following steps are for installation of the hoist pump.5. Install the O-ring seal on the hoist pump flange, and lubricate it with clean hydraulic oil.6. Put pump (4) in position on the pump drive, and install two bolts (2) that hold it.7. Install the O-ring seals on pump inlet tube (1) and outlet line (3). Install the lines onto the pump.Disassemble Hoist Pump
START BY:a. remove hoist pump 1. Thoroughly clean the outside of the pump. Remove O-ring seal (1) from the pump.
Do not damage the surface of the pump when the pump is installed in a vise.
2. Put the pump in position in a vise with soft jaws as shown. Remove bolts (4) that fasten flange (2) to the pump body. Remove any burrs or sharp edges from drive gear shaft (3). Put a thin layer of grease on the shaft. Lift the flange off the pump body. Keep the flange as straight as possible when it is removed. 3. Remove two lip-type seals (5) and the spacer from the flange. 4. Remove O-ring seal (6) from the groove in flange (2). 5. Remove top isolation plate (8), ring retainer (7), O-ring seal (9) and back-up ring (10) from the pump. 6. Lift gear (3) until pressure plate (11) is clear of the body. Remove the pressure plate. 7. Remove drive gear (3) and idler gear (12) from the body.
Use extra care when the lower pressure plate is removed from the pump body. Do not use force to remove the pressure plate.
8. Remove lower pressure plate (13). Keep the pressure plate as level as possible when it is removed.9. Remove the bottom isolation plate, ring retainer, O-ring seal and back-up ring from the body.Assemble Hoist Pump
1. Clean all parts thoroughly. Check all parts for damage or wear. See Inspection in Gear-Type Pump Service Manual, Form No. REG00984.2. Put clean SAE 10W oil on the bores of the pump body. 3. Install isolation plate (3) with the rounded edge. Install the isolation plate in the body with the rounded edge down. The isolation plate goes toward the inlet side of the pump. Put back-up ring (2) in position. Put O-ring seal (4) in position in the back-up ring. Put ring retainer (5) in position behind the O-ring seal. Be sure all parts are in place.
Use extra care when pressure plate (1) is installed into the pump body. Do not use force to install the pressure plate.
4. Install pressure plate (1) in the body with the bronze side up.