Service Manual User Manual

Section 9
9-82
9.9.5 Pilot Select Manifold
The pilot select manifold (Fig. 9– 57) is a precisely-
machined block located inside the rear cover, secured at
its four corners by capscrews and lockwashers to the
main control valve plate assembly (Fig. 9– 51) near the
left inside frame rail. The pilot select manifold contains
ports for cartridge valves and hose fittings.
DO NOT loosen, disassemble or attempt to adjust any of
the cartridges unless specifically instructed by Sky Trak
to do so!
Figure 9– 57. Pilot select manifold.
a. Pilot Select Manifold Replacement
1. Park the vehicle on a firm, level surface, fully retract
all hydraulic cylinders, ground the attachment (if any),
place the travel select lever in neutral (N), engage the
park brake switch and shut the engine OFF.
2. Unlatch, unlock and open the engine cover. Allow the
hydraulic fluid to cool.
3. Label or otherwise mark all of the hydraulic hoses
and solenoid wire terminal leads in relation to the
pilot select manifold. Disconnect the wiring, and cap
all hoses, fittings, etc.
4. Remove the four 1/4-20 x 2-1/2 Grade 5 hex-head
capscrews (31, Fig. 9– 51), 1/4-20 hex nuts (34) and
1/4” lockwashers (29) securing the manifold (1) to the
main control valve plate bracket (5).
5. Remove the pilot select manifold (1) from the vehicle.
Wipe up any hydraulic fluid spillage in, on, near and
around the vehicle.
b. Pilot Select Manifold Disassembly, Cleaning,
Inspection and Reassembly
1. Secure the pilot select manifold in a suitable bench
vise if possible. Remove the solenoid coils (Fig. 9–
57) and cartridge valves from the manifold.
2. Clean all components with a suitable cleaner before
inspection.
3. Inspect internal passageways and parts for wear,
damage, etc. If inner surfaces of the pilot select
manifold do not display an ultra-smooth, polished
finish, or are damaged in any way, replace the
manifold in its entirety. Most often, dirty hydraulic fluid
causes failure of internal seals and damage to the
polished surfaces within the component.
Note: Always replace seals, O-rings, gaskets, etc. with
new parts to help ensure proper sealing and operation.
c. Pilot Select Manifold Installation
1. Place the pilot select manifold (1, Fig. 9– 51) into
position on the main valve plate bracket (5) at the left
rear inner frame wall of the vehicle.
2. Install the four 1/4-20 x 2-1/2 Grade 5 hex-head
capscrews (31), 1/4-20 hex nuts (34) and 1/4”
lockwashers (29) to secure the pilot select manifold
to the main valve plate bracket (5). Torque fasteners
to 9 lb/ft (12 Nm).
3. Prime the pilot select manifold by adding a small
quantity of fresh, filtered hydraulic oil through the port
holes before attaching the hoses.
4. Use new O-rings as required. Reattach and secure
all hoses, clamps, wire terminals, etc.
5. Check the routing of all hoses, wiring and tubing for
sharp bends or interference with any rotating
members, and install tie wraps and/or protective
conduit as required. Tighten all tube and hose
clamps.
WARNING: Hot hydraulic fluid can cause
severe burns. Wait for hydraulic fluid to cool
before servicing any hydraulic component.
WARNING: Escaping hydraulic fluid under
pressure can penetrate the skin, causing seri-
ous injury. Relieve hydraulic pressure before
servicing any hydraulic component.
Cartridge Valve
Solenoid Coil
Pilot Select
Manifold
MS1990
WARNING: Avoid prolonged engine operation
in closed areas with inadequate ventilation.
Failure to properly ventilate exhaust fumes can
result in death or severe personal injury.
Model 3606 • Origin 10/99