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804±544 Pump Service
WARNING
To reduce the risk of serious bodily injury, including fluid injection, splashing in the eyes or on the skin, or injury from moving parts, always follow the
Pressure Relief Procedure Warning on page 5
before proceeding.
NOTE: The following metric wrenches are needed: 5 mm, 13 mm and 22 mm. Repair kits are available. Refer to the individual repair sections and the pump parts page for more details. For the best results, use all parts in the kits.
NOTE: There is a tool kit to aid in servicing the pump. P/N 800±271 includes tools to aid in the removal of packing retainers.
Valves
NOTE: For a set of six valves, order P/N 801±472.
1.Remove the hex plug from the manifold using a 22 mm socket.
2.Examine the o±ring under the hex plug and replace it if it is cut or distorted.
3.Remove the valve assembly from the cavity; the assembly may come apart.
4.Install the new valve. Install the o±ring and hex plug; torque to 33 ft±lb (45 Nm).
NOTE: Retorque the plug after 5 hours of operation.
Pumping Section
1.Remove the eight capscrews and lockwashers from the manifold using a 5 mm wrench.
2.Carefully separate the manifold from the crankcase.
NOTE: It may be necessary to tap the manifold lightly with a soft mallet to loosen.
CAUTION
Keep the manifold properly aligned with the ce- ramic plungers when removing to avoid damage to the plunger or seals.
3.Carefully examine each plunger for any scoring or cracking and replace as necessary.
Servicing the Plungers
NOTE: Plunger repair kit, P/N 801±474 is available to replace retainers, o±rings, washers and backup rings for three cylinders.
1.Loosen the plunger retaining nut five to six turns, using a 13 mm wrench. Push the plunger towards the crankcase to separate the plunger and retaining screw.
2.Remove the nut from the plunger and examine the o±ring, backup ring and copper bearing/gasket washer. Replace these parts, if necessary, using kit 801±474.
3.Remove the plunger and flinger from the plunger shaft. Clean, examine and replace parts as necessary.
4.Inspect the plunger shaft for oil leakage from the crankcase. If leaking is obvious, replace the oil seals. Otherwise, DO NOT remove these seals as they cannot be reused. An oil seal kit is available to replace the seals.
5.Lightly grease the flinger and oil seal, if it is being replaced and replace them on the plunger shaft. Then install the plunger.