Spewing coolant from reservoir cap

[03cobraFL]

Lately my friend has been having problems with his reservoir spewing coolant from the cap. This only happens when he's running the air conditioning though. His engine is freshly rebuilt after the last one blew a head gasket and overheated. Could the cap threads be warped? Could there be air trapped in the system somewhere? Is there a proper burping procedure someone could direct me to? Any input would be great.

Thanks

 

[thelpb]

Is it still overheating or just spewing?

Burping these cars can be a mofo... there are lots of threads on it. All involve filling the system from the crossover pipe. Having the front of the car up in the air helps some too.

 

[03cobraFL]

The car doesn't overheat, it just spews fluid out the cap when the car is parked. This generally only happens when the air conditioning was used. His last engine overheated, but the engine in the car now is freshly rebuilt. This whole crossover pipe thing looks like a PIITA. What's the purpose of a crossover pipe?

 

[01cobravortech]

FWIW, I overheated 2xs on my 01 Cobra and 1x in my 03. I had to replace the stock reservoir tank all 3xs after failing to stop the leaks with new radiator caps. If you're certain that she's burped properly and a new cap hasn't stopped the leaking, then I'd go with a new tank.

 

[03cobraFL]

Any idea on what tank to get? I was looking at another OEM tank or maybe a Canton.

 

[01cobravortech]

I've had the Canton, I currently have the Moroso. I've also replaced it with a straight up stock tank. It all depends on what suits your fancy.