TM 5-3895-346-14
POWER STEERING
PUMP OVERHAUL
3.
Press outer needle bearing onto shaft. The edge of the bearing must be 1/64 inch below the shaft
seal shoulder when assembled. This provides for shaft end play of approximately .010 to .015 inch.
NOTE
Tools for installing bearings can be made from round stock the outside diameter of
which is slightly smaller than the outside diameter of the bear- ing and the inside
diameter slightly larger than the shaft diameter. Do not score or otherwise damage
the shaft during this operation.
4. Position the seal on the shaft- end of the body, being careful not to damage seal. Using special tool,
(refer to Service Tools in Service, Inspection and Maintenance) press seal in until it engages the shoulder in the
body. This shoulder acts as a positive stop for the seal. Do not overpress as damage to the seal will result.
5. VTM28 and VTM40 Pumps-Carefully install shaft to prevent damage to shaft bushing and oil seal
surfaces.
6. VTM42 Pumps-Press inner needle bearing into the body with an arbor press. Install shaft seal in the
body in the same manner. Press outer ball bearing on shaft and assemble small snapring onto shaft. Install
shaft assembly in the body. Insert large snapring in body to retain ball bearing.
Cover and Cartridge
1. Install locating pins in pump body. Install ring over pins in correct direction of rotation.
2. Install rotor with chamfered edge of splined hole in or toward pump body. The chamfer facilitates
assembly.
3. Install vanes with their radius edge toward the inner ring contour.
4. Install the adapter plate and O-rings. (VTM28 and VTM40 only.)
5. Oil the cartridge with clean hydraulic oil and install pressure plate.
6. Install O-rings. Install pressure plate spring and cover. Tighten cover screws to 25-30 ft lb torque.
7. Install pressure-compensating spring in relief valve bore. Insert valve assembly with the hex toward
the spring. Install plug with O-ring in bore and hold it in position while driving a new retaining pin.
Reservoir and Manifold
1. VTM27, VTM28, and VTM42 Reservoir-Install O-rings on reservoir mounting pad on cover. Position
reservoir on pad, being careful not to unseat O-rings. Install capscrews, washers, and reservoir stud and lock-
nut. Install filter element. Be certain it is located over reservoir return tube orifice. Install filter retainer spring,
flat washer, and cotter pin. Install reservoir cover, gasket, washer, and thumb screw. Replace dipstick
assembly. Rotate pump shaft by hand to check for free operation of pump.
2. VTM27, VTM28, and VTM42 Manifold-Install O-rings in pump cover and secure manifold to pump
body with screws. Copper washer is used on screw where tapped hole enters oil passage.
3. VTM40 and VTM41 Reservoir-In- stall the two pump mounting bolts in the body flange on VTM40
models. In- stall a new O-ring on adapter plate. Install reservoir so the hole is aligned with the cover discharge
port. Install a new O-ring on the discharge fitting and install fitting to secure reservoir. Be careful that the O-
ring is not damaged as it is forced through the hole in the reservoir.
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