Thomas SAF-T-LINER C2, Maintenance Manual

Page: 55 / 176

See Section 20.07 of the Saf-T-Liner C2 School Bus
Workshop Manual for replacement instructions, or
take the vehicle to an authorized Freightliner dealer.
1. With the engine shut down, rotate the fan at
least one full turn by hand. It should have a
smooth, steady drag. If it does not, replace the
fan clutch.
2. Check for physical damage to the fan or fan
shroud.
3. Check for correct drive belt alignment and ten-
sion. For specifications, see
Group 01 of the
Saf-T-Liner C2 School Bus Workshop Manual , or
take the vehicle to an authorized Freightliner
dealer.
4. Check for wear of the fan clutch bearings. There
should be no side-to-side or in-and-out move-
ment of the fan clutch.
5. Do all of the checks in Section 20.00 of the Saf-
T-Liner C2 School Bus Workshop Manual , or
take the vehicle to an authorized Freightliner
dealer.
20–04 Coolant Heater Check,
Webasto
1. Using compressed air, clean any accumulated
debris or dust from the heater and enclosure
box. Inspect all components for wear or damage.
2. Check that the batteries are in good condition. If
the voltage is too low or too high, the heater will
automatically shut down. Check the wiring har-
nesses for damage. Replace the harnesses if
necessary.
3. Check the air intake port for obstructions. Care-
fully check the air intake tube for any restrictions
or damage, and repair or replace the tube if nec-
essary.
4. Check the exhaust system for restrictions or cor-
rosion. Replace any damaged parts.
5. Change the fuel filter, if so equipped. Inspect the
fuel line for damage, restrictions, or loose con-
nections. Repair or replace the line if it is dam-
aged.
6. Inspect all coolant lines and clamps for leakage,
restrictions, or damage. Replace the lines as
needed. Inspect the coolant circulation pump for
leakage. Repair or replace the pump if it is dam-
aged.
7. Run the heater at least once a month for 10 min-
utes.
8. Check the water and fuel connections for leak-
age. Tighten the hose clamps if needed.
20–05 Coolant System
Maintenance, Electric
Vehicle
WARNING
Do not remove or loosen the radiator cap until the
cooling system has completely cooled. Use ex-
treme care when removing the cap. A sudden re-
lease of pressure from removing the cap prior to
the system cooling can result in a surge of scald-
ing coolant that could cause serious personal
injury.
1. Inspect the cooling system (lines and valves) for
leaks. Repair leaks as needed.
2. Ensure that the coolant pump is operational and
that each coolant loop is full without any air
pockets.
3. Ensure that the cooling fan operates properly.
4. Inspect the coolant level and ensure there is suf-
ficient coolant in the system. The coolant should
be between the FULL and LOW marks on the
surge tank. Add coolant as needed with a 50/50
mixture of organic acid technology (OAT) coolant
and distilled water.
5. Check the condition of the coolant. If the coolant
shows scale, rust, silica-gel, oil, or has a frothy
scum, the vehicle must be taken to a Freightliner
dealer to have the contaminate source found and
fixed, and the cooling system chemically flushed.
Engine Cooling/Radiator
20
Saf-T-Liner C2 School Bus Maintenance Manual, May 2021
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