MCi Crusader II 1989 Maintenance Manual page 387

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12-7
MC-9 MAINTENANCE MANUAL
..:IGHT ADJUSTMENT
The correct coach body-to-axle clearance which should be
maintained is shown in.Figures 12-5 and 12-6. It should not be
necessary to make an adjustment under normal service condi-
tions. However, if an adjustment is necessary, it is made by
changing the position of the overtravel lever in relation to the
overtravel control body. The lever should be moved up to raise
the level of the coach body, and down to lower
it.
Check that air
pressure is above 100 psi (690 kPa) and raise coach to the
specified height
CAUTION: Always adjust on "flll cycle." If It
11
necu1ry
to lower coach height, rete••
sufficient air to be well below clearance and
adlust
to specHled clearance.
NOTE: Ride height should be. rechecked
after road tHHng.
When it is found that the coach is falling below the correct
level after being parked for a period of time, the following
procedure should be carried out
1. Support coach by placing blocks under body at jacking
points.
2. Open drain cock in air filter and vent all air from system.
3. Locate the suspension system height control valve which
1s applicable to the side of the coach which is low. One height
control valve controls both front air beams or springs; the rear
air beams or springs are controlled by two height control valves
,.... one left hand side and one right hand side.
4. Disconnect the air line (inlet from air tank) and remove the
adapter assembly (figure 12-8) and discard.
5. Remove the two small filter screens located behind the
adapter assembly .
. 6. Clean with solvent and compressed air.
7. Replace the two small screens and install a new adapter
and reconnect air line.
8. Charge the air system, remove the blocks and check the
height control valve for leaks.
Lfl
pd
Figure 12-8. Height Control Valve Adapter and Screens.
OVERTRAVEL LEVER
CENTER POSITION ADJUSTMENT
The following procedure is to adjust the over.travel lever:
1. Clean the exterior of the height control valve.
2. Remove delay piston retaining ring, cover. and O-ring
from control valve assembly, then drain off the silicone fluid.
3. Remove exhaust fitting and exhaust screen from control
valve.
4. Referring to figure 12-9. scribe a line 1-3/8" (34.9 mm)
from plug end of overtravel lever control body.
5. Place valve assembly in vise as shown in figure 12-9.
6. If vacuum source is available. attach supply hose to valve
exhaust port using Sun Tester fitting No. 115-3 or equivalent Do
not apply vacuum at this time.
7. Attach air pressure supply hose to air inlet port. Do not
apply pressure at this time.
8. Locate dial indicator in position as shown in figure 12-9.
Move overtravel lever to full air exhaust position - top of delay
piston flush with top of bore - without overtraveling (position
"C" Figure 12-10). Relocate indicator push rod to just contact
1-3/8" (34.9 mm) mark on control body and reset indicator dial
to zero at this point (position C).
MOUNT CONTROL
VALVE LEVEL
Figure 12-9. Dial Indicator Locations.
9. Move overtravel lever to full air intake position without
overtraveling (position" A" Figure 12-1 0)(delay piston at bottom
of bore). Take indicator reading which may vary 0.60" to 0.190" ·
(1.52 mm - 4.82 mm).
10. Repeat steps 8 and 9 above to recheck this reading.