Front Air Springs; Inspection; Removal - PREVOST H3-41 Maintenance Manual

SECTION 16 : SUSPENSION
2. Using a caliper, measure dimension "A" on
Figure 30.
3. With a lever tool, exert sufficient force under
the upper A-arm as to separate the upper A-
arm from the upright in order to have the ball
joint to its maximum extent. Measure
dimension A again. If the difference between
the two dimensions is greater than 0.060"
(1.5mm), then the ball joint should be
replaced.
FIGURE 30: UPPER A-ARM BALL JOINT
4.15

FRONT AIR SPRINGS

Two "rolling lobe" type air springs are used with
the independent front suspension, one at each
wheel. These air springs are special and use the
complete piston as an extra reservoir to lower
the spring stiffness. Front air springs are
attached to the subframe and to uprights.
FIGURE 31: AIR SPRINGS

4.15.1 Inspection

1. Check operation of air springs.
38 PA1621 Maintenance Manual All Series | Section revised October 2018
2. Visually inspect bellows for evidence of
3. With the primary air system at normal
NOTE
If air spring is removed from vehicle, bellows
can be lightly inflated and submerged in water
to detect any leakage. If leakage is detected,
replace air spring.
To prevent personal injury, do not apply more
than 10 psi (69 kPa) air pressure to the
dismounted air spring.

4.15.2 Removal

16116
NOTE
Front air springs can be removed without
removing the entire suspension assembly.
1. Jack up the vehicle using the axles jacking
2. Safely support the front of the vehicle at the
3. To gain access to a given air spring, the
Only the recommended jacking points must be
used as outlined in Section 18, "Body" in the
maintenance manual.
Always adequately support the IFS assembly
when lifting up the vehicle to avoid maximum
16052
extension of shock absorber.
4. Exhaust compressed air from accessory air
cracks, punctures, deterioration, or chafing.
Replace the air spring if damage is evident.
operating pressure (122 - 140 psi (841 - 965
kPa)), coat all suspension
connections and bellows mounting areas with
a water and soap solution. Bubbles will
indicate an air leak, and none is permissible.
Repair or replace defective parts.
WARNING
points.
recommended body jacking points.
corresponding wheel can be removed.
CAUTION
CAUTION
tank by opening drain cock under reservoir.
air line