Piston Rod Nut Torque Values
Description
Rod Size:
inches
Torque: lbf·ft
(N·m)
Anchorlok Tandem Chambers All 15–25 (20–34)
MGM Tandem Chambers All 25–35 (34–47)
Bendix Service Chambers
1/2 20–30 (27–41)
5/8 30–50 (41–68)
Midland Service Chambers
1/2 20–30 (27–41)
5/8 33–90 (45–122)
Table 1, Piston Rod Nut Torque Values
5. See if the chamber piston rod is in line with the
slack adjuster. Misalignment can cause the pis-
ton rod to rub on the non-pressure chamber and
cause a dragging brake. Reposition the brake
chamber on the mounting bracket, if necessary.
6. Inspect the condition of the hose(s) to the brake
chamber. Check carefully for chafing, restrictions
such as kinking or bending, and make sure the
hoses are properly supported. Replace a dam-
aged hose with the same size hose. With the
service brakes applied, check for leaks at the
hose-to-chamber connections. Any leaks are
probably caused by loose connections or by a
damaged hose fitting. Eliminate all leaks.
On chambers equipped with an external breather
tube, make sure that the flexible elbows are in
place and that the connector tube is inserted into
each elbow 1/2 inch (13 mm).
DANGER
Read and follow all applicable warnings and in-
structions in Group 42 of the
Business Class
®
Trucks Service Manual
for repairs to the
service/parking brake chambers. These chambers
contain a power spring, which if released, could
cause serious injury or death.
7. Inspect the exterior surfaces of the chamber for
damage. Make sure the breather holes in the
non-pressure section(s) are open and free of de-
bris. Using the instructions in Group 42 of the
Business Class
®
Trucks Service Manual
, replace
any damaged parts.
8. On parking brake chambers equipped with inte-
gral release bolts, lubricate the bolt with thread
anti-seize compound. Check the tightness of the
bolt. For torque values, see the applicable brake
chamber section in Group 42 of the
Business
Class
®
Trucks Service Manual
.
CAUTION
If the external breather tube is missing or incor-
rectly installed, road dirt and debris can adversely
affect the operation of the brake chamber. Once
inside the chamber, dirt and debris cause the in-
ternal parts to deteriorate and shorten their lives.
9. On brake chambers equipped with an external
breather tube, make sure the flexible elbows are
in place and the connector tube is inserted into
each elbow 1/2 inch (13 mm).
10. On all parking brake installations, check for pres-
ence of an end cover cap or dust plug and make
sure the cap or plug is securely snapped into
place.
Service Brake Operation and
Leakage Checking
DANGER
Do not loosen or remove the parking brake clamp
ring (see Fig. 1) for any purpose at any time. The
parking/emergency brake section is not intended
to be serviced. Serious injury or death may result
from sudden release of the power spring.
Before doing any repairs or adjustments on a
service/parking brake chamber, read the appli-
cable warnings and instructions in the applicable
brake chamber section in Group 42 of the
Busi-
ness Class
®
Trucks Service Manual
.
1. Apply the service brakes and check that the pis-
ton rods move out promptly, without binding.
2. Release the service brakes and check that the
piston rods return to the released positions
promptly, without binding.
DANGER
Read and follow all applicable warnings and in-
structions in Group 42 of the
Business Class
®
Trucks Service Manual
for repairs to the
service/parking brake chambers. These chambers
contain a power spring, which if released, could
cause serious injury or death.
Brakes42
Business Class Trucks Maintenance Manual, October 199842/4
To Next Page
Loading...
