Haldex S-ABA, Service Manual

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12
Frequently Asked Questions
1. Will the side of the brake adjuster with
the face plate always face in?
No. Haldex adjusters are normally unhanded.
Always install with the adjusting hex pointing
away from the air chamber.
2. Why is there resistance when backing
off the adjuster?
It takes approximately 20-25 lb. ft. of torque to
back off the adjustment hex on a new brake
adjuster. (A ratcheting sound should occur.)
3. How far do I back off the automatic
brake adjuster at a brake reline?
1/2 turn. (NOTE: for the first 1/8 turn you may
not hear the ratcheting; this is normal.)
4. How do I know if I need an offset,
angled or straight-armed adjuster?
Haldex manufactures the right adjuster arm for
your specific application. Haldex adjusters are
unhanded (no lefts or rights) in the majority of
applications. Please refer to the Haldex Parts
and Cross Reference Guide for your specific
application (L00090).
5. Why does my replacement ABA look
different from the original I removed?
The Haldex ABA replacement adjuster has been
designed to fit a number of applications. It is the
same original equipment quality and design of
the adjuster you removed; however, it may look
different on the outside. If you use all the parts
included in the kit, the results will be the same
as the original equipment adjuster.
6. Why is the applied stroke pressure
tange 90-100 psi at the reservoir?
This is the pressure recommended by thE
Commercial Vehicle Safety Alliance (CVSA).
Anything beyond 100 psi measure deflection
within the foundation brake and not true
pushrod stroke.
7. Some brake chambers have round
port openings and some square;
what is the difference?
Standard brake chambers are identified by round
ports. Long stroke chambers are identified by
square ports and trapeziod ID tags.
8. Can I vary the amount of
lining-to-drum clearance by moving
the control arm?
No. That clearance is set at the factory. If long
or short stroke continues, please refer to the
Foundation Brake Checking Procedures on pages
9 & 10 of this manual.
9. Can I use an air ratchet on the
adjuster?
No. It will damage the internal mechanism of the
adjuster and render it inoperative.
10. Can I access the adjuster through the
rear cover?
No. Do not tamper with the rear cover - it will
release the factory set pressure on the spring and
destroy the adjuster and its ability to properly
function.
11. How much control arm bushing
and anchor stud pin wear is
acceptable before replacement is
required?
No more than 1/16”.
12. What is the acceptable amount of
camshaft bushing wear?
Automatic adjuster cannot compensate for
worn foundation brake parts. Please refer to
the foundation brake manufacturer’s
recommendations for maximum bushing and
camshaft wear limits.
13. Can wheel bearing adjustment
affect the brake adjuster?
Yes. Improper wheel bearing adjustment could
result in improper brake adjustment. It is
necessary to refer to the axle manufacturer’s
wheel bearing adjustment recommendations. A
loose bearin preload could cause a tight brake.
14. Are all Haldex automatic brake
adjusters pre-lubed?
Yes. All Haldex brake adjuster are lubricated
at the factory. Please consult the Service and
Lubrication Section on Page 6 of the manual.
(continued on page 13)