TM 5-3895-373-20
REFERENCE INFORMATION
HYDRAULIC CYLINDER CIRCUITS
HOPPER LIFT CYLINDER - PRESSURE CHECK PROCEDURE
1.
With paving machine running at high idle, raise
hopper wing 6 to 8 in. above hopper- wing-down
position.
2.
Use cribbing and hydraulic jack to relieve weight
of hopper wing on lift cylinder. Make sure lower
cylinder
pivot
pin
turns
freely
in
cylinder
mounting knuckle.
Make sure cylinder is not under load
before removing hydraulic hose from
hopper cylinder extend port of stack
valve output manifold. Hydraulic oil
under pressure can penetrate skin or
damage eyes.
3.
Disconnect hydraulic hose from stack valve
output manifold extend port (A2 for left hand
cylinder or A4 for right hand cylinder). Plug
hydraulic hose with high-pressure #6 JIC (9/16-
18) plug. Cap off open manifold port with
protective cap.
Make sure personnel are clear of
hopper
wing
before
releasing
hydraulic jack. Falling hopper wing
can cause serious injury or death.
NOTE
When
hydraulic
jack
is
lowered,
hopper wing is expected to drop
slightly. This initial drop will make up
for fluid loss that occurred during
removal of supply hose from stack
valve manifold.
4.
Make sure all personnel are clear of hopper
wing. Release hydraulic jack. When hopper
wing is stable, use straightedge and pencil to
mark vertical position of hopper wing on
bulkhead. Mark ruler position on hopper wing.
5.
After 1/2 hour, mark settled position of hopper
wing on tractor bulkhead.
6.
Use jack and cribbing to remove load from
hopper lift cylinder. Slowly bleed pressure from
hose while removing plug. Reconnect cylinder
hose at stack valve. Start paving machine and
lower hopper wing. Measure distance between
pencil marks, and answer question in paragraph
D4 of flowchart.
After completing diagnostic checks, install right access
cover per TM 5-3895-373-10. Close right, center top left,
and center top right access doors per TM 5-3895-373-
10.
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