cooling question

[ENTDOC]

When my 351c warms up to about 190 degrees the purge outlet on the Moroso T filler starts to purge foamy coolant into the overflow tank.I would have thought by now all of the air in the system should have been purged.It settles down after a while and cooling has never been affected(175-180 when driving,190-210 idling).I do not seem to have a leak anywhere but this is concerning.I have a 16 lb cap on the T filler.Any thoughts? thanks;chuck

[Jack21]

As water heats up, it expands. As it cools down, it contracts.

Some cooling systems leave air space at the top of the radiator to allow for this expansion & contraction. Others, like your Cobra & mine have a coolant recovery system so the hot coolant can puke into the recovery tank when hot, and suck back into the engine when cool. Mine "Breathes" about 1/2 qt in and out of the engine. Am using a Stant 7# cap to avoid pressure build up that might push a hose off one of the crossover tubes. Thermostat is 180 deg year round.

[ENTDOC]

Thanks Jack,I guess as long as it does not overheat I should not worry. chuck

[KobraKarl]

Chuck ,

If the feed tube dosnt go below the coolant level in your recovery tank when cold , you could be pulling in air as you cycle from hot to cold.....

KK

[Edley Rondinone]

The "foamy" part of 'Doc's statement seems to have me worried...now I am not a mechanic, but would not having foam in the coolant indicate a contamination problem? I am just theorizing here...