barngal6

When I start up in the morning (not sure if its happening in the afternoon, just started driving again)
I hear this kind of mellow whoosh and a watery gurgle, maybe like fluid going down a drain...
its very brief and doesn't come back while I'm driving,
I'll have to check if it comes back when I start up several times in a row.

I just rebuilt the vac pump and repaired some of the vac hoses...
also drained the radiator and replaced new radiator hoses,
also changed drive belt but water pump seemed sound
all heat vents inside are working properly

what could it be?

Wicked500R

mine does it too

CarlJensen

Not to worry. Mine did the same. Remove radiator cap from COLD engine and start it up, the air in the system should come to the top of the radiator in a couple of minutes and you can top off and close it up. I had to shake mine a bit to get all the bubble out. An air slug can form in the engine and it moves on start up, what you hear is the bubble going through the heater core and tubes.

barngal6

Ahhh....sigh of relief.
I did a bunch of stuff recently and it makes me happy that I don't have to redo anything

thanks!