Cooling system weirdness
Thread Starter
Drifting
Joined: Jul 2003
Posts: 1,613
Likes: 0
From: Orlando FL
Cooling system weirdness
the car sat for a week while the hurricane mess was cleaned up. i checked the cooling system. the overflow tank was filled to the top and the radiator was about 3 inches low. i know for a fact that this wasn't the case last time i drove it. the radiator cap is new, but its one of those pressure release style ones with the red tab. this is the second time that the car has sat and this situation has arose. WHY does this keep happening? its really a pain to have to refill the cooling system by pulling the coolant sensor (to remove all the air), etc. every time the car sits for a few days.
Drifting
Joined: Nov 2002
Posts: 1,593
Likes: 0
From: Mobile AL
St. Jude Donor '05
I'd say go back to the factory style cap. This one may be opening up too soon and allowing the liquid to escape, then closes up not allowing the cooling system to suck it back in.
Le Mans Master
Joined: Dec 2002
Posts: 6,715
Likes: 2
From: Santa Teresa New Mexico
The car gets hot, the coolant expands, and when the engine off in a hot soak mode, the coolant goes to the expansion tank and stays there till theres room in radiator for it.
Thats how its designed to work.
Thats how its designed to work.
Thread Starter
Drifting
Joined: Jul 2003
Posts: 1,613
Likes: 0
From: Orlando FL
redwing, i half agree with you. as the engine gets hot, the coolant expands and overflows into the purge tank, but as the engine cools, the coolant condenses and creates a vaccum pulling the coolant out of the purge tank back into the radiator (which is why there is only 1 hose going in and out of the purge tank).
if that was what was happening, then when the engine was cool (like after sitting for 5 days) the purge tank would be essentially empty. in my case, its FULL. and it doesn't stay full after just a single days drive/cool down. it only seems to over flow after sitting for DAYS (well beyond a standard heating/cooling cycle).
so my thought is that somewhere in the system there is residual pressure that is finally pushing the coolant beyond the cap and into the coolant overflow tank after the car sits for long periods of time....
my question is WHERE is the pressure coming from, or WHY is this happening??
if that was what was happening, then when the engine was cool (like after sitting for 5 days) the purge tank would be essentially empty. in my case, its FULL. and it doesn't stay full after just a single days drive/cool down. it only seems to over flow after sitting for DAYS (well beyond a standard heating/cooling cycle).
so my thought is that somewhere in the system there is residual pressure that is finally pushing the coolant beyond the cap and into the coolant overflow tank after the car sits for long periods of time....
my question is WHERE is the pressure coming from, or WHY is this happening??
Team Owner
Joined: Sep 2003
Posts: 20,179
Likes: 673
From: Freedom is never more than one generation away from extinction.
St. Jude '03 thru '24
Originally Posted by Southern Comfort
just possible.....the high winds created a low pressure situation outside of the radiator and drew the water out of the rad and into the overflow....just a guess
Instructor
Joined: Aug 2004
Posts: 108
Likes: 0
I think that the overflow coolant is not going back to the radiator. That's why your overflow bottle keeps filling up. Maybe like the other guy said to change your radiator cap, it may be letting coolant out but not back in for some reason 
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