Re: Gas tank selector

["Chris and Ranae Procyk" <procyk19@domain.elided>]

>with and they warned me that Buna-N is not the optimal choice for
>gasoline. They believe it will break down faster. They suggested
>Bitron-A as the best material. Nitrile is a second choice. Any


You mean Vitron?  I got an O-ring for my gas tank at MMC's and I think it
was Vitron.  Only place I could find that had anything near the size.  They
list (www.mcmaster.com):

Buna-N, Vitron, Kalrez, Silicone, Polyurethane, Ethylene Propylene, Teflon,
and Neoprene.  Like I said, I didn't quite understand the spec's table, but
I think the listing we want is "Aromatic Hydrocarbons (*Fuel Oil C or
Toulene)"???  For that, the ratings are "poor" for Buna-N, "excellent" for
Vitron, Kalrez, and Teflon, and fair/poor/not recommended for the rest.

Note: Buna-N is "excellent" for "Allphatic Hydrocarbons (Fuel Oil A)".  But
I'm pretty sure we are guzzling (and leaking) Aromatic HCs!

I was wondering about the teflon, since that seemed the best overall.  But I
picture it as a flaky, hard stuff (that is, the only application I know of
is the ole frying pan).  I didn't know if it would compress right to make a
good seal for the gas tank, and I don't know if the teflon coating might
wear off under the rubbing of the valve movement.  It is listed as "poor"
under abrasion.