910193 - Hydraulic Impact Wrench
Phone: (262) 637-9681
4.2021 Rev 2.1
Page
18
of
30
Wrench Disassembly and Reassembly for Repair
Motor Disassembly
See Motor Housing & Valve Handle Assembly Drawing on page 28.
1. Remove the impact mechanism as described in the Impact Mechanism Removal and Installation
section (Refer to Page # 13).
2. Remove the eight 1/2 - 13 socket head cap screws (24) and lock washers (23) securing the motor
housing assembly (13) to the valve handle assembly (19).
3. With the motor housing assembly (13) in a vise, press on the splined end of the main shaft (17) with
one hand and support the valve handle assembly (19) with the other.
Press the valve handle assembly, gears and O-ring out of the motor housing assembly
Do not
pry or in any way excessively force the valve handle assembly off of the motor housing
assembly.
4. Remove the large O-ring (16) from the motor housing assembly.
5. Remove the idler gear (18), idler shaft (15) and main shaft (17).
6. If the relief adjustment screw (42), O-ring (41) requires replacement, loosen the jam nut (43) and
remove the relief adjustment screw. Be sure to count the number of turns required to remove it so it
can be replaced in the same position.
Motor Cleaning and Inspection
Cleaning
Clean all parts with a degreasing solvent. Blow dry with compressed air and wipe clean. Use only lint-
free cloths.
Bushing (Motor Housing and Valve Handle)
The inside of the bush
ings (14) should be gray in color. If a significant amount of yellow
-bronze
shows, bushing replacement is required. Inspect shafts for corresponding wear and replace as
required.
Gear Chamber (Motor Housing)
The gear chamber bores and end faces around the bores should be polished, not rough or grooved.
The flat surfaces around the chamber and bolt holes should be fl at and free of nicks and burrs that
could cause misalignment or leaks.
Gears
Both gears should have flat, straight tips without nicks. They shoul
d have a smooth even polish on
the teeth and end faces. Discard the gear if cracks are present.
Motor Housing Assembly
The gear running surfaces should show two inter-connecting polished circles without a step or
roughness.
Note:
If abnormal wear occurs in excess of normal polishing, both shafts and associated bushings
must be replaced. The hydraulic system should be thoroughly flushed and the filter replaced
before further operation of the wrench.