VCCA Home Forums TECHNICAL - 1945 AND EARLIER 1933-1936 35 Chevy Standard Radiator Needs Help

Hi,
I have a new radiator, rebuilt motor, rebuilt water pump and an old cap with a brand new gasket. I put on an over flow tank and water is going into it, but it is still boiling and spraying out of the radiator cap (which is on tight). It is spraying all over the hood and the window. Can someone tell me what to do.
Any suggestions would be appreciated.

The cap gasket is not sealing tight. Does the everflow have a stand pipe or something to relieve pressure. If not pressure is building up in the coolping system and blowing out around the cap gasket.
Try two gaskets.

Thanks so much. I will have to check that out.
I think that there is no pressure release any were I can see.
I will double check.
Maybe just a small hole in the top of the over flow tank would be enough.
Thanks for the quick reply.
35gene

I had a similar situation with my '35 Std. What I finally figured out was the rubber between the gasket and the cap was
collapsed snd so the gasket no longer formed an efective seal.
Through trial and error I found that a piece of Windshield
washer hose (from a late model car) was exactly the right
diameter to form a good seal. Do you have a temp guage? Is the
engine overheating when this happens? A stuck thermostat could
be a cause, or a cracked head, or a blown head gasket could be
allowing combustion gas and pressure into the cooling system
with the engine cold and the cap off, start the engine and look
for bubbles when you open the throttle; there should be none!
Cracked heads and blown gaskets are not uncommon for this engine. I have NOS '36 head on mine. Phil Lipton