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How do I go about getting the air out of the cooling system?

I have a problem getting all the air out of the cooling system after a thermostat change. What do you recommend?

Asked on 30 October 2017 by Iain McDougall-Bell

Answered by Honest John
The standard method is, from cold, to turn the heater valve to max. Then take the pressure cap off the expansion tank, then run the engine up to temperature until coolant starts geysering out of the expansion tank, then (wearing gardening gloves to protect your hands) screw the cap back on.

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