BRAKES (CONTINUED)
SYMPTOM
PROBLEM: REMEDY
SINGLE BRAKE DRAGGING
OR LOCKED
Broken internal brake component:
locate and replace broken
part.
Flat spot on cam roller or cam shaft:
replace and lubricate.
Improper adjustment:
adjust slack adjusters.
Spider bushing or cam bracket bushing binding:
lubricate or
replace bushing.
Improper lubrication:
lubricate per
Figure 4-1.
Worn brake shoe bushing:
replace bushing.
Brake drum distortion:
replace drum.
Broken brake chamber spring:
replace spring.
Brake chamber pushrod binding:
re-align brake chamber
bracket.
Air brake line loose or broken:
tighten or repair.
UNEVEN BRAKES
See “SINGLE BRAKE DRAGGING OR LOCKED”
Restriction in hose:
locate restriction and remove.
Worn brake linings:
reline brakes.
Grease on linings:
reline brakes.
Broken slack adjuster:
replace slack adjuster.
Leaking brake chamber diaphragm:
replace diaphragm.
BRAKES APPLY TOO SLOWLY
Brakes need adjusting or lubrication:
adjust or lubricate as
needed.
Low air pressure in brake system (below 105 PSI):
check
tractor air system.
Restricted tubing or hose:
locate restriction and remove.
Defective relay valve:
clean or replace.
Call Factory or see qualified Trailer/Brake Technician
BRAKES RELEASE TOO SLOWLY
Brakes need adjusting or lubrication:
adjust or lubricate as
needed.
Brake rigging binding:
align brakes or replace bent parts.
Exhaust port of relay valve restricted or plugged:
clean
valve.
Tractor pressure too low:
Adjust to provide 105 psi min.
ALL BRAKES DO NOT RELEASE
Air system improperly connected to tractor:
tighten or
adjust connections.
Brake valve on tractor is applied:
release brake.
Relay emergency valve in emergency position:
check line
pressure and check valve.
Restricted tubing or line:
locate restriction and remove.
Defective tractor protection valve:
troubleshoot tractor air
system.
Parking brakes locked:
troubleshoot air system.
Moisture in air system:
Check air system
Tractor pressure too low:
Adjust to provide 105 psi min.
5-4
Summary of Contents for 317B
Page 3: ...MODELS 317B 318 319 TRAILER OPERATOR S MANUAL PURCHASED FROM DATE ADDRESS PHONE NO SERIAL NO...
Page 8: ......
Page 14: ...3 2 Figure 3 1 Front Trailer Terminology Figure 3 2 Rear Trailer Terminology...
Page 18: ...3 6 Figure 3 4 Hydraulic Controls...
Page 24: ...3 12 Figure 3 5 Steps for Loading and Unloading...
Page 30: ...3 18 Figure 3 10 Dock Leveler Operation...
Page 34: ...3 22 Figure 3 12 Front Extension Bulkhead...
Page 36: ...3 24 Figure 3 13 Rear Impact Guard and Antilock Brake System...
Page 40: ...4 2 Figure 4 1 Lubrication Points...
Page 45: ...4 7 Figure 4 2 317B 318 319 Wiring Diagram...
Page 46: ...4 8 Figure 4 3 Remote Wiring Diagram...
Page 52: ...4 14 Figure 4 6 Checking Axle Alignment CURBSIDE DRIVER SIDE Figure 4 7 Examples of Camber...
Page 56: ...4 18 Figure 4 10 Axle and Brake Assembly...
Page 62: ...4 24 Figure 4 13 Inboard Mount Hub and Drum Figure 4 14 Three Spoke Wheel and Drum...
Page 66: ...4 28 Figure 4 18 Mounting Tires and Wheels Figure 4 19 Stud Tightening Sequence...
Page 69: ...4 31 Figure 4 20 Dock Leveler Leg Assembly...
Page 80: ...5 10 NOTES...