JLG 450A_AJ Series II Service Manual - Manual (Page 316)

SECTION 5 - HYDRAULICS
5-26 – JLG Lift – 3121180
IF CYLINDER IS TEST PRIOR TO INSTALLATION ON MACHINE,
USE EXTREME CARE TO INSURE OUTER END OF ROD IS SUP-
PORTED. USE A TRAVELING OVERHEAD HOIST, FORK-LIFT, OR
OTHER MEANS TO SUPPORT OVERHANGING WEIGHT OF
EXTENDING ROD.
5.2 HYDRAULIC PUMP (GEAR)
Disassembly
NOTE: The following general instructions also apply to mul-
tiple section gear pumps. The only extra parts are the
coupling between drive shafts and center distance
plate which divides the two pump sections. This
repair procedure also applies to ”W” series Gear
Motors.
1. It is very important to work in a clean work area
when repairing hydraulic products. Plug ports and
wash exterior of pump with a proper cleaning sol-
vent before continuing.
2. Remove port plugs and drain oil from pump.
3. Use a permanent marker pen to mark a line across
mounting flange, gear housing and end cover. This
will assure proper reassembly and rotation of pump.
4. Remove key from drive shaft if applicable.
5. Clamp mounting flange in a protected jaw vise with
pump shaft facing down.
6. Loosen four metric hex head bolts.
7. Remove pump from vise and place on clean work
bench, remove the four hex head bolts and spacers
if applicable.
8. Lift and remove end cover.
9. Carefully remove gear housing and place on work
bench. Make sure rear bearing block remains on
drive and idler shafts.