JLG 660SJ Service Manual - Manual (Page 235)

SECTION 5 - HYDRAULICS
3121202 – JLG Lift – 5-25
Minor Repair and Replacement
Minor repairs may be performed, following the procedures
in this section.
Cleanliness is a primary means of assuring satisfactory
transmission life, on either new or repaired units. Cleaning
parts by using solvent wash and air drying is usually ade-
quate. As with any precision equipment, all parts must be
kept free of foreign materials and chemicals.
Protect all exposed sealing surfaces and open cavities
from damage and foreign material.
It is recommended that all gaskets and O-rings be
replaced. Lightly lubricate all O-rings with clean petroleum
jelly prior to assembly. All gasket sealing surfaces must be
cleaned prior to installing new gaskets.
SHAFT SEAL
Lip type shafts are used on Series 40 - M46 pumps and
motors. These seals can be replaced without major disas-
sembly of the unit. However, replacement of the shaft seal
requires removal of the pump from the machine.
1. Remove the retaining ring from the housing.
2. Carefully remove the seal from the housing bore.
The face of the seal may be punctured with a sharp
instrument (such as a screw driver) to aid in prying
the seal out, or a slide hammer type puller may be
used to remove the seal. Care must be taken so as
not to damage the housing bore or shaft. Once
removed, the seal is not reusable.
3. Prior to installing the new seal, inspect the sealing
area on the shaft for rust, wear, or contamination.
Polish the sealing area on the shaft if necessary.
4. Wrap the spline or key end of the shaft with thin
plastic to prevent damage to the seal lip during
installation. Lubricate the inside diameter of the new
seal with petroleum jelly.
Figure 5-27. Variable Displacement Pump