Thermo King T-1000R, Maintenance Manual

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Engine Maintenance 9-10
Checking the Antifreeze
Check the solution concentration by using a temperature compensated antifreeze hydrometer or a refractometer designed for
testing antifreeze. Maintain a minimum of 50 percent permanent type antifreeze concentrate and 50 percent water solution to
provide protection to -30 F (-34 C). Do not mix antifreeze stronger than 68 percent permanent type coolant concentrate and 32
percent 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 drain cock 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 allow it to drain out of the drain cock until it is clear.
b. Close the drain cock 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 drain cock to drain water and flushing solution.
3. Run clear water into the radiator, and allow it to drain out of the drain cock until it is clear. When water has finished draining,
close drain cock.
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.
7. Mix one gallon of the appropriate permanent type antifreeze concentrate and one gallon clean water in a container to make a
50/50 mixture. (Do not add antifreeze and then add water to the unit. This procedure may not give a true 50/50 mixture
because the exact cooling system capacity may not always be known).
8. Refill the radiator with the 50/50 mixture.
Engine Thermostat
For the best engine operation, use a 71 C (160 F) thermostat year round.
CAUTION: Avoid direct contact with hot coolant.
CAUTION: Avoid direct contact with hot coolant.