coolant

[RichardH]

Hi again folks
If I can ask another prospectively dumb Q about cooling systems?
I have a GTD based '40 (with the Alloy Header tank situated behind the driver) that takes approx 12Litres of coolant. I have a new (12psi, i think) cap on the header tank, but every time I run the car it pushes out what seems to be between a pint and a litre of coolant through the overflow pipe. I assume that this is just heat expansion of the coolant; but, because the header tank is only just above level with the top of the engine, I am concerned about coolant levels, and therefore top up the tank before every trip.
This is, annoying, if nothing else, to have to carry a bottle of coolant wherever I go, because the water pushed out is just lost.
Short of having a larger header tank made, which I do not wish to do, is this normal?
Should I not be concerned?
I assume a higher pressure Rad cap might help, but would put a strain on the other components and seals?
what do other people find?
would a capture tank be a worth while addition, or is that being silly?

 

[Mark Clapp]

My system is about 3 gallons. I use one gallon of anti-freeze (green stuff of any brand) for the corrosion package and 2 gallons water. I also add 1-2 cans (whatever the recommended amount is for 3 gallons) of water-wetter (Purple Power) and my temps stay at 180F. I don't drive much below 40F so anti-freeze in not an issue. Richard, I would definitely install an overflow tank. Your main tank just has to have a port just below the pressure cap. The coolant that is puked over is then sucked back by the vacuum created when the system is cool. I keep the header (fill) tank full and some in the overflow tank that raises and falls with the temp of the system.

 

[40 Bud]

Early GTD's (pre 1989) had the fill bottle mounted to low. The later cars moved the fill bottle up so that the rad cap is just below the top of the rear window. This required cutting a notch in the rear clip stiffing panel that supports the flat panel covering the engine around the carb.

 

[Randy V]

I've always used at least 1 gallon of Antifreeze in anything that had an alloy radiator, block or heads because I don't believe that distilled water will keep the corrosion at bay.. Also there needs to be a lubricant for the water pump seals / bushings (although most are sealed ball bearing now)..

Curious - What sort of a bugger is it to burp the cooling systems in the 40's?