Bubbling/gurgling sound

chvythndr · July 28, 2006

I heard something earlier and am not sure what it is. I got out of my truck (2002 Z71) and there was a bubbling/gurgling sound coming from the engine. Is this coolant? Is it normal? Maybe b/c my A/C was on...?

getcrunk88 · July 30, 2006

usually that means that your engine is overheating if it is coming from your radiator

dewfpo · July 30, 2006

A couple of things come to mind.

A coolant cap that is not holding the spec'd pressure and I'd suggest adding a 'water wetter' or similar product in the correct mix and see if you still hear the gurgling or bubbling under the same conditions.

I had a similar issue with Ford Topaz years ago. Right after shutting off a very hot engine the 'hot spots in the engine head would cause localized boiling of the coolant. The above two items solved the problem.

The cap keeps more pressure in the system so it boils at a higher temp and the 'water wetter' breaks the surface tension of the water and gets better contact with the heads so they cool a little better reducing the severity of the hot spots.

DEWFPO