Head gasket?
Thread Starter
Safety Car
Joined: Sep 2005
Posts: 4,213
Likes: 643
From: Orange County Ca
Head gasket?
I thought my coolant temp reading were looking a little odd, so I checked out the system to make sure everything is OK. The elect. connector to the sending unit wasn't on tight, and that seemed to correct the readings. I also removed the fill cap from the serge tank--stone cold-- and about 1/2 pint of coolant overflowed. Seems like the level is usually lower than this when cold. After running it a few days, I checked the tank again today. Stone cold again, and it still puked about a 1/2 pint. The top radiator hose is emepty, so the system isn't full.
So, when cold, should there be enough pressure in the system to cause it to overflow when opened? The system was pressurized after sitting for about a week, and there doesn't seem to be any coolant in the oil.
The car is a '69 427, 390 hp, mostly stock with '71 low compression heads. I rebuilt it about 4 yrs and 22k miles ago.
Is a head gasket on the way out?
So, when cold, should there be enough pressure in the system to cause it to overflow when opened? The system was pressurized after sitting for about a week, and there doesn't seem to be any coolant in the oil.
The car is a '69 427, 390 hp, mostly stock with '71 low compression heads. I rebuilt it about 4 yrs and 22k miles ago.
Is a head gasket on the way out?
Le Mans Master
Joined: Oct 2006
Posts: 7,123
Likes: 433
From: Gladstone MO
C3 of Year Finalist (appearance mods) 2019
It's got an air bubble in it. Burp it. If it's not blowing bubbles in the expansion tank when it's running, head gaskets are probably not a problem. Start it up with the cap off, and keep adding water as it heats up. I've got the same system and it can be a PITA to get full.
