coolant overflow bottle
#1
#4
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here is what happens....
when your car builds up pressure in the coolant system, the pressure pushes the plunger on the radiator cap.....the plunger will then no longer block the hole going to the overflow tank and pulls or pushes the coolant into or out of the tank......if your not getting the coolant back then it is a bad cap or a non efficient water pump
when your car builds up pressure in the coolant system, the pressure pushes the plunger on the radiator cap.....the plunger will then no longer block the hole going to the overflow tank and pulls or pushes the coolant into or out of the tank......if your not getting the coolant back then it is a bad cap or a non efficient water pump