Thermo King 914970, Manual

Page: 97 / 186

Engine Maintenance
97
Antifreeze Maintenance Procedures
As with all equipment containing antifreeze,
periodic inspection on a regular basis is required
to verify the condition of the antifreeze. Inhibitors
become worn out and must be replaced by
changing the antifreeze. Change green or
blue-green engine coolant every two years.
Do not mix green or blue-green engine coolant
with ELC (red) engine coolant.
The factory recommends the use of a 50/50%
antifreeze mixture in all units even if they are not
exposed to freezing temperatures. This antifreeze
mixture will provide the required corrosion
protection and lubrication for the water pump.
Checking the Antifreeze
Check the solution concentration by using a
temperature compensated antifreeze hydrometer
or a refactometer designed for testing antifreeze.
Maintain a minimum of 50% permanent type
antifreeze concentrate and 50% water solution to
provide protection to -30 F (-34 C). Do not mix
antifreeze stronger than 68% permanent type
coolant concentrate and 32% water for use in
extreme temperatures.
Changing the Antifreeze
1. Run the engine until it is up to operating
temperature. Stop the unit.
2. Open the engine block drain and accumulator
tank drain, and completely drain coolant.
Observe coolant color. If the coolant is dirty,
proceed with a, b, and c. Otherwise go to step
3.
a. Run clear water into radiator and
accumulator and allow it to drain out of
the block until it is clear.
b. Close the block drain and install a
commercially available radiator and block
flushing agent, and operate the unit in
accordance with instructions of the
flushing agent manufacturer.
c. Open the engine block and accumulator
drain to drain water and flushing solution.
3. Run clear water into the radiator, and allow it
to drain out of the block and accumulator until
it is clear.
4. Inspect all the hoses for deterioration and the
hose clamp tightness. Replace if necessary.
5. Loosen the water pump belt. Check the water
pump bearing for looseness.
6. Inspect the radiator cap. Replace the cap if the
gasket shows any signs of deterioration.
CAUTION: Avoid direct contact with hot
coolant.
1. Drain
Figure 24: Accumulator Tank Drain
CAUTION: Avoid direct contact with hot
coolant.