PDWA Valve O-Ring Material

[71tr]

I'm rebuilding my PDWA brake valve and need to replace the tiny o-rings inside. Does anyone know what material these are made of? I've read it is Ethylene Propylene, but want to confirm with the gallery.

 

[Tinster]

EP? Was EP around in the early 70's?
The EP I have seen is very pale, light
green in color.

d

 

[PeterK]

I bought a bag of 50 of these from McMaster a while ago. PM me with your address and I'll mail you a few (I think I now where they are!) Think it was EPDM?

 

[Tinster]

EPDM? Maybe

EPDM gets eaten pretty quickly by most oils
including cooking oils.

Maybe neoprene?

d

 

[PeterK]

geez Dale, you made me have to go out to my cold shop and see. Actually today the shop is pretty bearable without the woodstove on.

They ARE EPR EPDM Size 008 5/16OD x 3/16ID x 1/16W. Don't lube with other than brake grease or silicone grease, especially don't use cooking oil.

If you are running cooking oil in your brakes, no wonder your car can't stop!

 

[dklawson]

EDPM is a great sealing rubber for everything except oils. As mentioned, brake fluids aren't oil so this is the seal material of choice for brake fluid. It offers excellent high-temperature performance.

McMaster is one of my favorite sources for supplies.

 

[71tr]

Thanks for all the comments and suggestions. I agree, McMaster is like a giant toy chest.