should coolant bubble back into overflow??
Thread Starter
Instructor
Joined: Mar 2006
Posts: 246
Likes: 1
From: west melbourne florida
should coolant bubble back into overflow??
i have a 79 vette and today i drove it home parked in the garage and shut it off and heard the anti freeze bubbling back into the over flow is this normal??? never noticed it before
Burning Brakes
Joined: Oct 2004
Posts: 904
Likes: 0
From: Murphy NC
Its normal. When the coolant gets hot it expands and goes into the overflow tank. When you shut your engine off the coolant will pick up a little extra heat because its not being cooled by the fan anymore. As everthing starts to cool back down coolant will then be drawn from the reservoir back into the radiator. 
Race Director
Joined: Apr 2003
Posts: 19,349
Likes: 654
From: Tampa, Florida
Its normal. When the coolant gets hot it expands and goes into the overflow tank. When you shut your engine off the coolant will pick up a little extra heat because its not being cooled by the fan anymore. As everthing starts to cool back down coolant will then be drawn from the reservoir back into the radiator.
As long as your overflow is at the 'minimum' or 'cold' line when cold your good to go.
