I think I found the ideal gasket material to use when modding the petcock to be manually (instead of automatically (using vacuum)) selectable.

Go to:

McMaster-Carr

Enter "viton" into the search box.

Click on the "Viton Flouroelastomer Rubber" link.

Click on the "Sheets, Bars, and Strips" link.

From there, you can choose your options.

It looks like you can get 6" square sheets of standard Viton rubber for $6.29 (1/32" thick), $9.57 (1/16" thick), or $14.24 (3/32" thick).

In order to make shipping costs reasonable, you may want to "fill out" the order with other goodies (never a problem when shopping at McMaster-Carr).

IHTH someone!

verslagen1 wrote on 02/01/10 at 11:28:17:


Are you talking about rebuilding the diaphragm?  If so, be advised that you can get Viton no thinner than a 1/32" sheet from McMaster-Carr, which seems a little thick to me (I could be wrong).  I've got an OEM Savage petcock in the garage, but I'm too lazy to take it apart and measure the thickness of the diaphragm.....unless you're really serious.  Let me know.

Perhaps you could rig something up from a section of material from a disposable Nitrile glove.  McMaster-Carr sells those also, in boxes of 50 or 100, with rubber anywhere from 4 to 8 mils thick.

http://www.mcmaster.com/#nitrile-gloves/=5mxuey

You can also get, from them, oil and acid resistant Nitrile gloves, with rubber anywhere from 9 to 22 mils thick.  You can find a link for these and many other gloves on the above link.

Lots o' options.

BTW, here is a good reference for researching various gasket materials' resistance to substances of all types:

http://www.allstategasket.com/chem_res_cht.asp#G