UNCONTROLLE
D IF P
R
INTE
D
ELECTRICAL AND MECHANICAL
ENGINEERING INSTRUCTIONS
VEHICLE H 983
Issue 1, Jul 11
17
66. Installation.
Install the yard release valve as follows:
a.
Install the valve in the mounting bracket, securing it with the panel mounting nut.
b.
Connect the air lines.
c.
Install the button.
d.
Install the roll pin to secure the button to the plunger.
Spring Brake Chamber
67. Removal.
Remove the spring brake chamber as follows:
Never attempt to ‘cage’ any spring brake which shows signs of structural
damage or significant corrosion. Handle damaged spring brakes with extreme
caution.
a.
Remove the plastic plug from the spring brake chamber housing.
NOTE
Prior to inserting the release tool into the chamber, fit the flat washer and nut to the
end of the tool.
b.
Remove the release tool (Table 2, Serial 4) from the chamber body and insert it into the spring brake
chamber, passing it through to the centre of the spring brake pressure plate.
c.
Rotate the release tool 90° to engage the lugs into the pressure plate.
NOTE
Pull the tool to ensure that the lugs are properly engaged in the pressure plate.
d.
Tighten the nut onto the release tool and continue turning, withdrawing the release tool from the
housing.
NOTE
This compresses the spring brake compression spring and releases the brake.
e.
Tag and remove the two air hoses from the brake chamber to ensure correct installation.
f.
Remove the cotter pin connecting the clevis assembly to the slack adjuster.
g.
Remove the two nuts and bolts from the mounting bracket and remove the spring brake chamber.
68. Installation.
Install the spring brake chamber as follows:
a.
Ensure that the spring brake compression spring is fully caged by the release tool.
b.
Attach the two hose stems to the chamber adapter housing.
c.
Fit the brake chamber to the axle mounting bracket and secure with the respective hexagon bolts, nuts
and washers.
d.
Connect the clevis to the slack adjuster.
e.
Connect the two air hoses, ensuring that they are connected to the correct ports.
f.
Remove the release tool from the spring brake chamber housing and return it to its stowage boss.
g.
Fit the plastic plug into the spring brake housing.
h.
Check the brake adjustment and adjust as required. Refer to Para 20 and 21.
