JLG 600SC_660SJC Service Manual - Manual (Page 292)

SECTION 8 - HYDRAULICS
8-32 – JLG Lift – 3121157
12. Place the O-ring onto the shaft bearing and lubricate
with petroleum jelly.
13. Slide the seal carrier assembly over the shaft and
into the housing bore. Press against O-ring. Hold
inward pressure against the shaft to compress the
cylinder block spring while pressing the seal carrier
into place.
14. Install the retaining ring.
Charge Pump
The charge pump may be disassembled to inspect
and clean, or to change the auxiliary shaft drive cou-
pling.
1. Remove auxiliary pump, if necessary.
2. Remove the screws retaining the charge pump
cover to the pump housing [Torx T45] (seven (7)
screws are used with the "no pad" or SAE "A" auxil-
iary mounting pad charge pump cover, while six (6)
screws are used with the SAE "B" auxiliary mounting
pad charge pump cover). Remove the charge pump
cover, gasket, and the cover locating pins.
3. Remove the gerotor cover assembly from the
charge pump cover or the back of the pump hous-
ing. Remove the gerotor cover O-rings. Two (2) O-
rings are used on the gerotor cover of all pumps.
(An additional O-ring was used on the gerotor cover
of very early production pumps with the SAE "A" pad
option.)
4. Remove the gerotor assembly from the gerotor
cover or pump housing.
5. Remove the gerotor drive pin and drive coupling.
Remove the gerotor cover locating pin from the
pump housing.
6. Each part should be inspected separately if they are
to be reused. If either of the gerotor assembly parts
needs to be replaced, they must both be replaced.
Always replace the O-rings and charge pump cover
gasket. Inspect the journal bearing in the gerotor
cover for excessive wear.
7. Prior to assembly, lubricate the gerotor assembly
with clean hydraulic oil.
8. Install the gerotor drive pin into the hole in the drive
coupling, and retain with grease or petroleum jelly.
9. Install the drive coupling onto the pump shaft with
the smaller outside diameter oriented away from the
pump shaft. Different couplings are used with the
different auxiliary pad options.
10. Install the gerotor assembly onto the coupling.
11. Install the gerotor cover locating pin into the pump
housing. Install the gerotor cover assembly over the
gerotor. The locating pin must engage the slot in the
gerotor cover.
NOTE: The charge pump rotation is determined by the loca-
tion of the gerotor recess and pressure balance hole
in the gerotor cover. Different gerotor covers are
used for clockwise and counterclockwise rotation
pumps.
12. Install new pressure balance O-rings onto the gero-
tor cover and retain with petroleum jelly or grease.
(An additional O-ring was used on the gerotor cover
of very early production pumps with the SAE "A" pad
option.)
13. Install the charge pump cover locating pins and a
new charge pump cover gasket.
14. Install the charge pump cover. The cover must
engage the gerotor cover and the locating pins.
Install the charge pump cover screws and torque
evenly [36-43 Nm (26-32 ft•lbf)].
15. If necessary, reinstall auxiliary pump.