Bendix Commercial Vehicle Systems BRAKE SYSTEM TROUBLESHOOTING GUIDE - Manual (Page 17)

15
BRAKE SYSTEMS DIAGNOSTIC GUIDE
POTENTIAL CONDITION/CAUSE ACTION (SERVICE MANUAL SECTION)
Contamination -
—No air dryer
Install air dryer
—Faulty air dryer Repair or replace
—Dirty or damaged filter Replace filter
—Desiccant debris Clean desiccant
—Incompatible oils Drain and refill with proper oil
—Leaking air tanks Repair or replace tank
—Mis-adjusted brakes Readjust brakes
Insufficient pushrod free travel:
• Pushrod length too long
Shorten pushrod to proper length
• Incorrect installation of slack adjuster Perform correct installation procedure (6)
Overadjusted slack adjuster:
• Incorrect in-service adjustment (manual)
Readjust using proper procedure
• Incorrect setup of external reference control arms Perform correct setup procedure
(Eaton-Haldex)
• Incorrect slack window (auto slacks) Replace with proper slack window (6)
• Contamination of internal parts (auto) Replace slack adjuster (6)
• False feedback to slack adjuster (review all Check lining clearances and hub/drum run-out (4)
foundation brake and wheel end problems)
• Auto slack installed and/or adjusted with spring Readjust with spring brake fully retracted
brake partially applied (low reservoir pressure)
• Performing downgrade braking using light drag Use snub method on downgrades
Cam flip over:
• Worn linings/drums
Replace linings/drums (3,5,6)
• Worn shoes/rollers Replace as necessary (3,6)
• Worn cam Replace cam (3,6)
Binding of camshaft in bushings:
• Corrosion
Replace bushings and lubricate (5)
• Lack of lubricant Lubricate with proper lubricant (2)
• Damaged bushings/journals Replace bushings/journals (5)
Drum out-of-round:
• Worn-out drum
Replace drum (3,6)
• Overloading of vehicle Don’t exceed legal weight rating of vehicle
• Over-aggressive linings Change lining friction rating
• Driver abuse Correct as required
• Incorrect turning of drum Perform correct drum turning operation (2)
• Performing downgrade braking using light drag Use snub method on downgrades
P
ARKING BRAKE WILL NOT HOLD/
DRAGGING BRAKES