JLG 530LRT, Service And Maintenance Manual

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SECTION 3 - CHASSIS, PLATFORM & SCISSOR ARMS
3-20 3121781
3.4 DRIVE MOTOR (SAUER)
Description
The drive motors are low to medium power, two-posi-
tion axial piston motors incorporating an integral servo
piston. They are designed for operation in both open
and closed circuit applications. The standard control is a
direct acting single line hydraulic control. The integral
servo piston controls motor displacement.
The motors are spring biased to maximum displace-
ment and hydraulically shifted to minimum displace-
ment. Minimum and maximum displacement can be set
with fixed internal stops. The large diameter servo pis-
ton allows smooth acceleration and deceleration with
relatively large circuit orificing.
Shaft Seal Replacement
REMOVAL
1. Remove the snap ring (1) retaining the shaft seal and
support washer.
2. Remove the support washer (2).
3. Carefully pry out the shaft seal (3).
To avoid damaging the shaft during removal, install a
large sheet metal screw into the chuck of a slide
hammer. Drive the screw into the seal surface and
use the slide hammer to pull the seal.
4. Discard the seal.
Bias spring
Servo piston
Swashplate
Output
Shaft
Piston
Slipper
Cylinder
Block
Endcap
Shaft
Seal
Bearing
Minimum
Angle
Stop
Valve plate
Figure 3-5. Drive Motor Cross Section
1
2
3
1. Snap Ring
2. Support Washer
3. Shaft Seal
Figure 3-6. Removing the Shaft Seal