Do you have a burping problem?

[UKjohnnycobra]

Do you have a burping problem? I don't mean after drinking a case of fizzy American beer, i mean eliminating air pockets from your engine. I have used a simple mod which works for me, and might be of interest.

My Cobra is self built and has a familiar problem, that is, the radiator is lower than the engine. I had tried all the burping methods available on this forum and others and despite that I still experienced unpredictable temperature changes and sudden coolant losses, which I think were die to air pocket hotspots. I tried filling the engine block through the temperature sender port, but I could not get rid of all the air. I have drilled the thermostat. The design is such that I couldn't add an expansion tank into the top hose which I've seen on other Cobras.

So I added an expansion tank at the back of the engine bay at the highest point available. This provides a header in addition to expansion and has a standard Lever Lock pressure relief radiator cap. I fill the system from here. A hose from the tank goes to the overflow pipe on the radiator fill neck. The radiator is fitted with a non pressure relief cap (available from Summit) which allows free flow through the overflow pipe. I then fitted a standard ball valve (from a plumbers supply) to an unused tapped port on my Edelbrock Performer intake manifold. The port is next to the distributor (see photo).

I can fill the system from the header tank and vent the air through the ball valve. Or, by adding a barbed fitting to the ball valve, I can add coolant through the valve, (using a large funnel on a long tube to provide hydro pressure) and vent through the Lever Lock, in which case the air is forced through the radiator overflow into the header tank.

I have the overflow from the LeverLock connected to an overflow tank as initially I did not know how much coolant expansion and overflow would be involved. After many runs the system has never lost fluid and has never overheated.

[FWB]

have one of these screwed into the top front of the intake. push to bleed off air
Moroso 63765 Moroso Cooling System Air Bleed Valve - Free Shipping on All Orders @ JEGS

[blown871]

Sounds like a dumb question... BUT.. have you had the front end higher than the back of car? This is how I learned to get the air out of systems over 30 years ago..................
Crack the rad cap......... and run.

[UKjohnnycobra]

To FWB

Yes I tried that and I prefer the ball valve as I can add coolant or vent air

[UKjohnnycobra]

Originally Posted by blown871

Sounds like a dumb question... BUT.. have you had the front end higher than the back of car? This is how I learned to get the air out of systems over 30 years ago..................
Crack the rad cap......... and run.

Not a dumb question. Problem is , my rad is so low compared to the engine it's all but impossible to raise the front high enough.

[FWB]

yes most of our cars, the rad is lower than the highest point of the cooling system in the block. the ford purge tank allows for that. or a purge tank of any type mounted as the highest point.

i have a cylindrical purge tank mounted forward, it is the highest point but i still get air trapped in the intake manifold, i installed the little valve and fixed the issue. i fill and top off at my purge tank.