Thomas SAF-T-LINER C2, Руководство по обслуживанию

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83–00 Safety Precautions
Safety Precautions in this section apply to all
procedures within this group.
DANGER
When working on the vehicle, shut down the en-
gine or motor, set the parking brake, and chock
the tires. Before working under the vehicle, always
place jack stands under the frame rails to ensure
the vehicle cannot drop. Failure to follow these
steps could result in serious personal injury or
death.
83–01 Air Conditioner
Inspection
1. Park the vehicle on a level surface, shut down
the engine, and set the parking brake. Chock the
tires.
2. Operate the heater and, if so equipped, the air
conditioner, to check for proper operation in all
modes.
3. Open the hood.
4. Check the condition of the refrigerant compres-
sor clutch assembly for visible signs of damage
due to excessive heat. If the friction surface of
the pulley shows signs of excessive grooving
due to belt slippage, replace both the pulley and
the drive plate.
5. Inspect the refrigerant compressor drive belt for
damage, and replace it if necessary.
6. Check the tightness of the compressor mounting
fasteners. The torque value for the mounting fas-
teners is 15 to 19 lbf·ft (20 to 26 N·m).
7. Inspect the drive plate. If the friction surface of
the drive plate shows visible signs of damage
due to excessive heat, make sure the refrigerant
compressor turns freely. If the compressor does
not turn freely, the compressor should be re-
placed. For instructions, see the applicable sec-
tion in
Group 83 of the vehicle Workshop
Manual , or take the vehicle to an authorized
Freightliner dealer.
8. Using a feeler gauge, check that the drive plate
clutch clearance is 0.016 to 0.031 inch (0.4 to
0.8 mm). If the gap is not even around the
clutch, gently tap down at the high areas. If the
overall gap is out of spec, remove the drive plate
assembly and change the shims as necessary.
For instructions, see the applicable section in
Group 83 of the vehicle Workshop Manual , or
take the vehicle to an authorized Freightliner
dealer.
9. Check that the wiring harness connector is not
damaged or loose. Replace the wiring harness if
it is damaged.
10. Check the overall condition of the air conditioning
hoses. Look for cracks, cuts, and abrasions on
the hoses. Replace damaged hoses.
11. Check for a buildup of road debris on the con-
denser fins. Using air pressure and a whisk
broom or a soapy spray of water, carefully clean
the condenser. Be careful not to bend the fins.
12. Close the hood.
83–02 HVAC Air Filter Cleaning
The HVAC air filter must be cleaned every 12
months or 8000 miles (12 872 km), whichever comes
first, to permit proper operation of the HVAC system.
1. Park the vehicle on a level surface, shut down
the engine, and set the parking brake. Chock the
tires.
2. Disconnect the batteries.
3. Remove the three lower HVAC cover Torx
screws; two at the bottom of the cover and one
on the right. Remove the cover.
4. Disconnect the wiring harness from the evapora-
tor probe, if equipped with air conditioning.
5. Remove the capscrews that attach the evapora-
tor service cover to the HVAC assembly. Remove
the evaporator service cover. See
Fig. 1 .
6. Pull the filter out of the HVAC assembly. See
Fig. 2 .
7. Clean the filter with a warm detergent solution.
Dry the filter before installing it.
8. Install the filter in the HVAC assembly.
9. Remove the condensate seal from the evapora-
tor service cover and install a new condensate
seal on the cover.
Heater and Air Conditioner
83
Saf-T-Liner C2 School Bus Maintenance Manual, June 2015
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