Chevrolet Chevette/1000 1976-1988 Repair Guide

Cooling System



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Fig. Fig. 1You can use an inexpensive tester to check anti-freeze protection

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Fig. Fig. 2Cutaway view of a typical cooling system flow

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Fig. Fig. 3Be sure the rubber gasket on the radiator cap has a tight seal

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Fig. Fig. 4Periodically remove all debris from the radiator fins

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Fig. Fig. 5Cooling systems should be pressure tested for leaks periodically

Once a month, the engine coolant level should be checked. This is quickly accomplished by observing the level of coolant in the recovery tank, which is the translucent tank mounted to the right of the radiator, and connected to the radiator filler neck by a length of hose. As long as coolant is visible in the tank between the Full Cold and Full Hot marks, the coolant level is OK.

If coolant is needed, a 50/50 mix of ethylene glycol-based antifreeze and clear water should always be used for additions, both winter and summer. This is imperative on cars with air conditioning; without the antifreeze, the heater core could freeze when the air conditioning is used. Add coolant to the recovery tank through the capped opening; make additions only when the engine is cold.

The radiator hoses, clamps and radiator cap should be checked at the same time as the coolant level. Hoses which are brittle, cracked or swollen should be replaced. Clamps should be checked for tightness (screwdriver tight only-do not allow the clamp to cut into the hose or crush the fitting). The radiator cap gasket should be checked for any obvious tears, cracks or swelling, or any signs of incorrect seating in the radiator neck.

To avoid injury when working with a hot engine, cover the radiator cap with a thick cloth. Wear a heavy glove to protect your hand. Turn the radiator cap slowly to the first stop, and allow all the pressure to vent (indicated when the hissing noise stops). When the pressure has been released, press down and remove the cap the rest of the way.


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Fig. Fig. 6The draincock is located at the bottom corner of the radiator

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Fig. Fig. 7Turn the drain cock to allow the coolant to drain into a suitable container

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Fig. Fig. 8Remove the cap from the coolant recovery tank, then ...

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Fig. Fig. 9... add the correct amount of 50/50 antifreeze and water mixture to the tank

The cooling system should be drained, flushed and refilled every two years or 30,000 miles, according to the manufacturer's recommendations. However, many mechanics prefer to change the coolant every year; it is cheap insurance against corrosion, overheating or freezing.

  1. Remove the radiator cap when the engine is cool. See the preceding CAUTION about removing the cap.

When draining the coolant, keep in mind that cats and dogs are attracted by the ethylene glycol antifreeze, and are quite likely to drink any that is left in an uncovered container or in puddles on the ground. This will prove fatal in sufficient quantity. Always drain the coolant into a sealable container. Coolant should be reused unless it is contaminated or several years old.

  1. With the radiator cap removed, run the engine until heat can be felt in the upper hose, indicating that the thermostat is open. The heater should be turned on to its maximum heat position, so that the core is flushed out.
  3. Shut off the engine and open the drain cock in the bottom of the radiator.
  5. Close the drain cock and fill the cooling system with clear water. A cooling system flushing additive can be used, if desired.
  7. Run the engine until it is hot again.
  9. Drain the system, then flush with water until it runs clear.
  11. Clean out the coolant recovery tank; remove the cap leaving the hoses in place. Remove the tank and drain it of any coolant. Clean it out with soap and water, empty it, and install it.
  13. Close the drain cock and fill the radiator with a 50/50 mix of ethylene glycol base antifreeze and water to the base of the radiator filler neck. Fill the coolant recovery tank with the same solution to the Full Hot mark. Install the recovery tank cap.
  15. Run the engine until the upper radiator hose is hot again (radiator cap still off). With the engine idling, add the 50/50 mix of antifreeze and water to the radiator until the level reaches the bottom of the filler neck. Shut off the engine and install the radiator cap, aligning the arrows with the overflow tube. Turn off the heater.