9
BRAKE SHOE AND LINING TROUBLESHOOTING CHART
SYMPTOM
CAUSE
REMEDY
1. Poor lining to drum
A. Bell-mouth drum.
A. Replace part.
contact.
B. Bent brake spider.
B. Replace part.
C. Bent or stretched brake shoe.
C. Replace part.
D. Undersize linings.
D. Replace linings.
E. Loose wheel bearing.
E. Correct as required.
F. Improper lining grind.
F. Regrind linings to drum radius
minus .015".
2. Linings tapered
A. Bell-mouth drum.
A. Replace parts.
across width.
B. Bent brake shoe.
B. Replace parts.
C. Bent brake spider.
C. Replace part.
D. Loose wheel bearings.
D. Correct as required.
3. Unequal wear on
A. Mismatched lining friction codes.
A. Replace linings.
in same brake.
B. Stretched shoe.
B. Replace part.
C. Flat spots on cam or roller.
C. Replace flat-spotted parts.
D. Worn anchor pin.
D. Replace part.
E. Worn cam shaft or bushings.
E. Replace part.
4. Unequal wear side
A. Mismatched lining friction codes.
A. Replace linings.
to side brakes,
B. Seized or binding cam shaft.
B. Clean and lubricate.
same axle.
C. Brake drum surface in poor condition.
C. Replace or turn I.D.
D. Loose wheel bearing,
D. Correct as required.
E. Relining one brake.
E. Reline both brakes together.
5. Wear on edge of
A. Wrong width lining.
A. Replace linings.
lining.
B. Holes improperly drilled in lining.
B. Clean and lubricate.
C. Wrong drum, or improperly machined. C. Replace or turn I.D.
D. Loose bearing adjustment; bearing
D. Correct as required.
spacer missing or too thin.
E. Improper wheel bearing or cone.
E. Correct as required.
F. Bent brake shoe.
F. Replace part.
G. Bent brake spider.
G. Replace part.
H. Worn axle spindle.
H. Correct as required.
6. Glazed linings
A. Overheating, due to unbalanced
A. Correct as required.
(hard and shiny)
braking system.
B. Wrong type linings for service involved. B. Replace linings.
7. Scored or grooved
A. Scored or worn drum, not machined
A. Replace or remachine.
linings and drum.
at reline.
B. Abrasive material between lining and
B. Clean, remove dirt and debris.
drum.
8. Loose lining.
A. Improper size rivets (too long, too
A. Re-rivet.
short, improper diameter).
B. Improper crimping of rivet.
B. Re-rivet.
C. Enlarged rivet holes in shoe.
C. Replace part.
D. Incorrect lining hole size or counter
D. Replace linings.
bore depth.
E. Rust build up on shoe table.
E. Clean, remove rust and paint shoe
