Need a new radiator cap

[J Witt]

I need a sealing cap for my radiator, which is a stock configuration 1936. I am running the 3 psi pressure valve on the overflow and the existing cap isn't sealing well. There some dribbles around the cap after any run at street/highway speeds over about 40 mph.

I have one of the high-buck caps with the bail on it, but it fits much worse than the old (brand unknown) cap I have. The old one also leaks a little.

Does anyone have a recommendation?

Thanks,

John

[1931 flamingo]

New gasket........................
Paul in CT

[petehoovie]

I went to ACE Hardware and purchased some rubber gasket material they sell in their plumbing section and made a new gasket to used on the cap for my '34. Worked like a champ. The material is available in various thickness. > http://www.acehardware.com/product/i...ductId=1272624
or > http://www.acehardware.com/product/i...uctId=22767006

• Product Type: Do It Yourself Gasket Kit
• Material: Rubber
• Contains three 6" x 6" squares: 1 red rubber 3/32" thick, 1 black fiber 1/32" thick, 1 cork 1/16" thick
• Cuts with scissors
• Use to make gaskets and washers

Rather than to use a scissors to cut the material, I used a compass circle cutter like this > https://www.amazon.com/OLFA-9911-Com...SIN=B000BK7NWC

[CaliforniaBorn36]

I had the same problem with my 1936 Bail style cap and did the same as petehoovie, but I just used a piece of old inner tube left over from replacing all my tires and tubes a few years ago.

[G.M.]

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Originally Posted by J Witt

I need a sealing cap for my radiator, which is a stock configuration 1936. I am running the 3 psi pressure valve on the overflow and the existing cap isn't sealing well. There some dribbles around the cap after any run at street/highway speeds over about 40 mph.

I have one of the high-buck caps with the bail on it, but it fits much worse than the old (brand unknown) cap I have. The old one also leaks a little.

Does anyone have a recommendation?

Thanks,

John

John if you read Skips instructions that should have came with his 3 LB
valve it says the stock caps don't seal tight enough to hold a few pounds
of pressure. You need to drill the rivet out of the cap and make a round
washer like seal from the 1/8th inch red rubber gasket material found in
hardware stores. Replace the rivet with a slotted SS 1/4-20 screw 3/4"
long with a lock washer and 2 nuts so it don't come loose. Make sure you remove and flush the new valve twice a year. G.M.