JLG 680S, Service And Maintenance Manual

Page: 400 / 530

SECTION 5 - BASIC HYDRAULICS INFORMATION & SCHEMATICS
5-64 3121234
Rotating Kit Assembly
DISASSEMBLY
Disassembly of rotating assembly is required for inspection
only.
1. Remove the nine piston assemblies, shoe retainer, and
shoe retainer pivot from cylinder barrel.
Inspection
• Examine the O.D. of the pistons for finish condition. They
should not show wear or deep scratches. Inspect the shoes
for a snug fit on the ball end of the pistons and a flat
smooth surface that comes in contact with the swashplate.
Do not lap piston shoes.
• Examine the shoe retainer for wear in the pivot area.
• Examine the pivot to insure smoothness and no signs of
wear.
• Inspect the cylinder barrel surface that makes contact with
valve plate. This surface should be smooth and free of deep
scratches. Do not lap piston block.
• The pistons should move freely in the cylinder barrel bore.
If they are sticky in the bore, examine the bore for scoring
or contamination.
2. To inspect pins and spring caution should be taken in
removing spring. The spring is highly compressed and
the retaining ring should not be removed without com-
pressing the spring safely.
The following parts are required to disassemble the cylinder
barrel:
To remove spring, place one of the flat washers over the
3/8 in. x 3-1/4 in. capscrew. Put capscrew through the center of
the cylinder barrel and apply the second washer. Let washer
rest on the three pins and retain with nut. Turning nut and
compressing spring inside the barrel. Use a pair of retaining
ring pliers and remove the internal retaining ring. Remove nut,
bolt, and the two washers from barrel. Remove the washer,
spring, second washer, three pins, and pin keeper at the same
time.
ASSEMBLY
1. To reassemble the rotating kit assembly complete the
following: Compress the pin keeper and install in the
spline of the cylinder barrel. Insta ll the three pins with
head end to the inside of the barrel and position in the
special grooves of the cylinder barrel spline.
2. Install the washer, spring, and second washer into the
cylinder barrel. Use the two 3/8 in. I. D. washers, nut, and
3/8 in. x 3-1/4 in. capscrew to compress the spring and
retain with retaining ring. Remove the nut. capscrew,
and the two washers.
3. Install the pivot onto the three pins, shoe retainer on the
pivot, and piston assemblies through the shoe retainer
and into cylinder barrel resting on shoe retainer.
2 ea. 3/8 in. I.D. x 1-1/8 in. O.D. flat washers
1 ea. 3/8 in. x 3-1/4 in. N.C. capscrew, and
1 ea. 3/8 in. N.C. nut
3
1
4
5
6
7
8
9
2
7
1. Piston assemblies
2. Shoe Retainer
3. Shoe Retainer Pivot
4. Retainer
5. Cylinder Barrel
6. Pins
7. Washer
8. Spring
9. Retaining Ring
Figure 5-98. Rotating Kit Assembly