Need a new radiator cap

J Witt

J Witt

Well-known member
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
 
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/index.jsp?productId=1272624
or > http://www.acehardware.com/product/index.jsp?productId=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-Compass-Circle-Cutter/dp/B000BK7NWC?tag=atomicindus08-20
 
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.
 
J Witt said:
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
Click to expand...

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.
 
You must log in or register to reply here.
Back
Top