SkyTrak 6036 Service Manual - Manual (Page 286)

Hydraulic System
8.70 Model 6036 Legacy
c. Unloader Valve Installation
1. Secure the unloader valve (Fig. 8-35, 1) to the
vehicle frame with the three hex-head capscrews (7),
the three lockwashers (8) and the three washers (9).
Torque the capscrews to 31 lb/ft (42 Nm). Secure the
check valve manifold (10) to the unloader valve with
the flange connection.
Note: ALWAYS replace seals, o-rings, gaskets, etc.,
with new parts to help ensure proper sealing and operation.
Lubricate seals and o-rings with clean hydraulic oil.
2. Connect the hydraulic lines to their appropriate ports
on the unloader valve or check valve manifold.
3. Check the routing of all hoses, wiring and tubing for
sharp bends or interference with any rotating
members. All tube and hose clamps must be tight.
4. Start the engine and run at approximately one-third
to one-half throttle for approximately one minute without
moving the vehicle or operating any hydraulic functions.
5. 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 tighten fittings or repair as
required before continuing. Wipe up any hydraulic fluid
spillage in, on, near and around the vehicle, work area and
tools.
d. Unloader Valve Pressure Check Test
1. Monitor the valve pressure at the VG test port
(Fig. 8-36, 7) on the unloader valve. It should be at
250-300 psi (17-21 bar) within moments after
starting the engine. Adjust the differential pressure
sense valve as required.
2. Check the pressure at the VG test port (Fig. 8-36, 7)
on the unloader valve while performing the boom lower
function. It should be 3000 psi (207 bar). Adjust the
relief valve as required.
8.12.2 Main Control Valve
The main control valve (Fig. 8-37, 1) is mounted on the
frame under the lower transmission cover.
Figure 8-37 Main Control Valve Location
WARNING:
Avoid prolonged engine
operation in closed areas with inadequate
ventilation. Failure to properly ventilate exhaust
fumes can result in death or serious injury.
WARNING:
Hydraulic oil leaking 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.
MA8330
Front
1