Thermo King SB-210, Manual

Page: 79 / 159

Engine Maintenance
79
Bleeding Air from the Cooling
System
Jiggle pin thermostats are original equipment on
units that have TK 482/486 engines. Jiggle pin
thermostats make it unnecessary to bleed the air
out of the engine block because they keep air from
being trapped in the engine block. Normally, all
but about 1.5 qt (1.4 liters) of coolant drain out of
the cooling system when it is drained. If
approximately half of the Cooling System
Capacity (see Specifications) seems to fill the
cooling system after it has been drained, air has
been trapped in the block. Bleed the air out of the
block using the following procedure:
NOTE: If an engine runs with air trapped in the
block, the engine may be damaged. The high
water temperature switch may not protect an
engine that has air trapped in the block, because
the high water temperature switch is designed to
protect an engine from overheating due to
failures in the cooling system.
1. Loosen the plug on the back of the water
pump below the thermostat cover until coolant
comes out of the plug fitting.
2. Tighten the plug.
1. Expansion Tank 5. Water Pump
2. Radiator Cap 6. Thermostat
3. Coolant Level Sensor 7. Thermostat Housing
4. Radiator
Figure 65: Engine Cooling System
1
2
3
5
4
7
6
CAUTION: IF YOU SUSPECT THAT
AIR IS TRAPPED IN THE BLOCK, DO
NOT START THE ENGINE WITHOUT
BLEEDING THE AIR OUT OF THE
BLOCK.