JLG 740AJ, Service And Maintenance Manual

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SECTION 5 - BASIC HYDRAULIC INFOR M ATION AND SCHE M ATICS
3121160 5-87
Shaft Seal Replacement
A lip type shaft seal is used in the pump and can be replaced
without major disassembly of the unit. Replacement of the
shaft seal requires removal of the pump from the machine.
REMOVAL
1. Using the appropriate snap-ring pliers, remove the
retaining ring (K010) from the housing.
2. Remove the shaft seal (K020) from the bore in the pump
housing and discard. Avoid damaging the pump hous-
ing or shaft. Puncture the face of the seal with a packing
hook, or use a slide-hammer type puller to remove the
seal.
INSTALLATION
1. Inspect the pump housing and new seal for damage.
Inspect the sealing area on the shaft for rust, wear, or
contamination. Polish the sealing area on the shaft if
necessary.
2. Lubricate the lip of the new shaft seal with clean hydrau-
lic fluid. Place a protective sleeve over the shaft end to
prevent damage to the seal during installation.
PREMATURE BEARING FAILURE CAN RESULT IF THE SHAFT SEAL CONTACTS
THE SHAFT BEARING. PRESS THE SEAL INTO THE HOUSING ONLY FAR ENOUGH
TO CLEAR THE RETAINING RING GROOVE.
3. Keeping the seal perpendicular to the shaft, press the
new seal into the housing just far enough to clear the
retaining ring groove. Install seal with the cupped side
toward the shaft bearing. Do not damage the seal dur-
ing installation.
4. Using the appropriate snap ring pliers, install the seal
retaining ring.
5. Remove the installation sleeve.
Control Assembly
K010
K020
Figure 5-133. Shaft Seal and Retaining Ring
C117
C118
6mm
C116
C117
C114
C115
C113
C200
C138
6mm
C136
C135
C134
C133
C132
C103A
C112
C106A
C106
3/16 in
11-14 N•m
[8-10 lbf•ft]
C103
3/16 in
11-14 N•m
[8-10 lbf•ft]
C300 (4pl.)
5mm
15-18 N•m
[11-13 lbf•ft]
C102 (2pl.)
4mm
7-11 N•m
[6-8 lbf•ft]
C107A
C107
3/16 in
11-14 N•m
[8-10 lbf•ft]
Figure 5-134. Control Assembly