Replacing the Gears and/or
Slider Assembly
1. Using a Phillips screwdriver, remove the four front cover
screws. Remove the front cover.
2. Start the engine (refer to the procedures in the Operation
section of this manual). Turn the pressure control knob
clockwise to its maximum pressure setting.
3. Toggle the pump ON/OFF switch between the ON and
OFF positions in short bursts until the slider assembly and
piston stop at the bottom of their stroke (in their lowest
position).
4. Turn off the engine and perform the Pressure Relief
Procedure.
5. Using a 11/16” open-
end wrench, loosen
and remove the fluid
hose from the fitting
on the back of the
fluid section.
6. Using a 3/8” hex
wrench, remove the
two socket screws
that secure the fluid
section to the pump
housing.
7. Remove the fluid
section by pulling it
straight down from
the pump housing
until the dowel pins
on the pump housing disengage from the fluid section
housing. Then, pull the fluid section forward to disengage
the piston from the T-slot on the slider assembly.
8. Using a 1/4” hex wrench,.remove the four socket screws
that secure the pump housing to the gear housing.
9. Slide the pump housing away from the gear housing.
10. Remove and clean the housing gasket. Replace if
damaged.
11. Slide the crankshaft assembly, with the two thrust washers
out from the gear housing side of the pump housing.
12. Remove the output gear assembly with the two thrust
washers.
13. Thoroughly clean the crankshaft assembly, the output gear
assembly, and all the thrust washers.
Connecting
Rod
Slider Bushing
Slider Assembly
Gear Housing
Pump Housing
Output Gear
Assembly
Thrust
Washer
Thrust Washer
Housing Gasket
Large Thrust Washer
Crankshaft Assembly
Cylindrical Thrust Washer
Pump Housing
Socket Screw
Fitting
Piston
Pump
Housing
Slider
Assembly
Front
Cover
Screw
Fluid
Section
Housing
Socket
Screw
Front
Cover
NOTE: If replacing the slider assembly, the fluid
section must be removed from the pump
housing.
10
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14. Inspect all parts for excessive wear and replace if
damaged or worn. If the crankshaft or output gear
assembly are replaced, replace the corresponding thrust
washers as well.
15. Inspect the pinion gear on the end of the drive shaft for
wear. Replace if damaged or worn (refer to the “Servicing
the Clutch Assembly” procedure in this section).
16. Slide the slider assembly up and out of the slider bushing
in the front of the pump housing.
17. Check the parts for wear.
a. If the slider bushing is scored or out of round it should
be replaced.
b. If the slider assembly is scored or the connection
between the connecting rod and slider assembly
exhibits movement other than pivoting movement, the
slider assembly should be replaced. The slider
assembly also should be replaced if the connecting rod
bearing shows signs of wear.
c. Any parts that will be reused should be cleaned
thoroughly, including the connecting rod. Also, clean the
crankshaft pin that the connecting rod bearing rides on.
d. If the slider bushing requires replacement, a press must
be used. Position the pump housing so that the
bushing is facing the arbor on the press. Position the
new bushing on top of the old bushing. Lower the
arbor on the press to contact the new bushing and
press the new bushing into the bore. As the new
bushing is pressed into the bore, the old bushing is
pressed out of the bore. The new bushing is in place
when it is flush with the bore wall on the pump housing.
18. Coat the output gear assembly and each side of its thrust
washers with fresh Lubriplate GR-132 grease. Place the
thrust washers on their proper shaft of the output gear
assembly.
19. Lubricate the output gear assembly with fresh Lubriplate
GR-132 grease. Insert the gear assembly into its bore in
the gear housing, gear end first. The teeth on the gear
will mate with the teeth on the drive shaft pinion.
20. Generously coat all surfaces of the cylindrical crankshaft
assembly thrust washer with fresh Lubriplate GR-132
grease.
21. Slip the flat end of the cylindrical thrust washer behind the
gear on the output gear assembly, lining its bore up with the
gear housing bearing bore for the crankshaft assembly.
22. Lubricate the crankshaft assembly gear with fresh
Lubriplate GR-132 grease. Slide the gear side shaft of
the crankshaft through the cylindrical thrust washer and
into its bore within the gear housing.
23. Position the pin on the end of the crankshaft towards the
bottom of the gear housing (the bottom dead center
position).
24. Lubricate both faces of the large crankshaft assembly
thrust washer with fresh Lubriplate GR-132 grease. Place
the thrust washer onto the crankshaft against the gear.
25. Place the housing gasket over the gear housing dowel pins.
26. Lubricate the outside of the slider assembly and the inside of
the slider bushing with oil. Fill the slider cup with Lubriplate
1242 grease (the slider cup is the area on the slider
assembly where the connecting rod and slider join and pivot).
27. Insert the slider assembly into the slider bushing so that
the small dimple on the face of the connecting rod faces
the open side of the pump housing.
28. Carefully place the pump housing assembly in front of the
gear housing assembly, lining up the gear housing dowel
pins with their corresponding holes in the pump housing.
Slide the pump housing onto the gear housing until there
is no gap between the housings and gasket.
NOTE: If any of the gears are worn and require
replacement, check the grease in the gear
housing for metal particles or shavings.
Remove the contaminated grease. Replace the
grease that has been removed with fresh
Lubriplate GR-132 grease.
