202
Air System
Condition
Possible Cause
Solution
Loose fitting
Check fittings at compressor and engine for leaks
and verify fittings are properly torqued.
Cracked coolant port
Replace
compressor.
Porosity in cylinder head
Replace
compressor.
Leaking of gasket internal
to the cylinder head
Replace
compressor.
Compressor leaks
engine coolant
None of the above, but
condition persists
Replace compressor.
Leaking of gasket internal
to the cylinder head
Cavitation or corrosion in
cylinder head
Replace
compressor.
Porosity in cylinder head
or cylinder head cracked
Replace
compressor.
Replace
compressor.
Compressor
pressurizes coolant
system or coolant
leakage to
compressor inlet
None of above, but
condition persists
Unloader leakage
Possible internal damage,
including worn or
damaged unloader piston
O-ring, porosity in
unloader piston bore, loose
leaking seal at unloader
piston bore
Replace
compressor.
Discharge line blocked due
to freezing or carbon
build-up
Check for trap (low spots) in lines.
Make necessary repairs.
Clear discharge line. Replace line if necessary.
Check for carbon build-up. If carbon build-up is
present, replace the discharge line.
Frozen or blocked line to
governor
Clear blocked line. Replace line if necessary.
Check for air dryer malfunction. Repair or
replace as required. Refer to the air dryer
manufacturerís maintenance manual for service
information.
Governor malfunction
Repair or replace the governor. Refer to governor
manufacturerís maintenance manual for service
information.
Improper cylinder head
bolt torque, machining
defect on cylinder head or
block, defective cylinder
head gasket
Inspect gasket. Replace if necessary. Verify all
bolts are properly torqued. If problem persists,
replace cylinder head.
Compressor head
gasket failure
None of the above, but
condition persists
Replace compressor.
Summary of Contents for LOW FLOOR
Page 18: ...Specifications 18...
Page 58: ...Preventive Maintenance 58...
Page 110: ...Engine 110...
Page 138: ...Transmission Driveline Rear Axle 138...
Page 182: ...Suspension 182...
Page 260: ...Air System 260...
Page 420: ...Electrical System 420 Deutsch DT Series Connectors...
Page 421: ...Electrical System 421...
Page 422: ...Electrical System 422 Deutsch HD 10 Series Connectors...
Page 423: ...Electrical System 423...
Page 424: ...Electrical System 424 Deutsch HD 30 Series Connectors...
Page 425: ...Electrical System 425...
Page 442: ...Heating Air Conditioning 442...
Page 492: ...Body and Interior 492 Figure 11 33 USSC Seat Assembly...
Page 493: ...Body and Interior 493 Figure 11 34 USSC Seat Suspension Assembly...
Page 495: ...Body and Interior 495 Figure 11 37 Seat Air Connections...