JLG sky trak mmv Service Manual page 394

Hydraulic System
h. Pump Installation
1. Place the pump (1) and a new oiled o-ring (2) into
position on the transmission. Align the pump gear
shaft coupling with the internal transmission gear so
that the machined teeth mesh together.
2. Align the bolt holes with the pump mount holes. Line
up the holes in the accumulator charge valve
mounting bracket with the pump flange. Secure the
pump and mounting bracket to the transmission with
four plain washers (4), lockwashers (3) and
capscrews (5). Torque the capscrews to 75 lb/ft (102
Nm).
3. If necessary, slide the T-bolt band clamp (6) onto the
pump inlet hose (7). Secure the hose to the inlet tube
assembly with the T-bolt band clamp.
4. Thread the front outlet hose (8) onto the connector
(9).
5. Thread the rear outlet hose (10) onto the connector
(11).
6. Prime the pump by filling the pump inlet opening with
fresh, filtered hydraulic oil from a clean container
before attaching the inlet hose (7).
7. Place a new oiled o-ring (12) into position over the
opening and secure the inlet hose (7) with two flange
halves (13), four lockwashers (14) and four
capscrews (15). Torque the capscrews to 31 lb/ft
(42 Nm).
7
6
15
14
13
12
4
3
5
1
9
11
8
10
9.96
2
8. Check all routing of hoses, wiring and tubing for
sharp bends or interference with any rotating
members. All tube and hose clamps must be tight.
WARNING:
operation in closed areas with inadequate ven-
tilation. Failure to properly ventilate exhaust
fumes can result in death or serious injury.
9. Start the engine and run at approximately one-third
to one-half throttle for about one minute without
moving the vehicle or operating any hydraulic
functions.
WARNING:
under pressure can penetrate the skin and
cause severe personal injury. DO NOT use
your hand or any part of your body to check for
hydraulic leaks. When checking for hydraulic
leaks, wear safety glasses and gloves to help
provide protection from spraying hydraulic oil.
Use a piece of cardboard or paper to search
for leaks.
10. Inspect for leaks and check all fluid levels. The
hydraulic reservoir oil level must be to the middle of
the sight gauge.
Note: Check for leaks and repair as required before
continuing.
i. Pump Test
Refer to Section 9.7, Hydraulic System Testing .
1. Perform a flow meter test on both pumps.
2. Check the load sense at the unloader valve.
3. Check the load sense at the accumulator charge
valve.
4. Check the system functions.
MM3551
Avoid prolonged engine
Hydraulic oil leaking
Model MMV Rev. 12/04