I have had no trouble with buna and mogas but it is rare that I have to
use mogas with any alcohol in it. Based on research I do replace things
like drain valve o-rings with viton o-rings if I have them apart. Viton
is fairly common and competitively priced now from industrial suppliers.
And I made sure to use appropriate grade automotive hoses and
components. I believe viton is safer with the highly varied mogas
mixtures these days especially with alcohol and other oxygenates. There
are lots of reports of problems with alcohol and buna aircraft rubber.
The MAM supplied gas caps might have buna seals and I can say that mogas
causes mine to swell up. They shrink back when removed and dried but I
ignore that and am still using the originals.
Ken
Jesse Jenks wrote:
Hi Ken, Since you have done the research, what about buna-N in the
fuel system? Thinking about auto gas in the future, and I got a
gascolator from Vans. I asked the tech guy if it was ok for auto gas
and he said yes, and that the gasket was buna-N. I did a quick google
search, but didn't find anything to confirm what he said. I guess
alcohol would be bad for it, and probably the o-rings in the
quick-drains too. I know my selector valve is ok..it's the Andair
one. I should have spent the $$ and got the Andair gascolator as
well. Thanks. JesseDate: Thu, 25 Nov 2010 20:54:36 -0500 From: klehman@albedo.net To:
rebel-builders@dcsol.com Subject: Re: [rebel-builders] Fw: moose
brake cylinders
Yes there is a bit more to it but IMO it makes no sense to use
anything but a mineral oil based product like 5606, dexron tranny
fluid, or hydraulic fluid in a light airplane. That makes common
buna-N o-rings the first choice. Cost, availability, low
temperature characteristics, environmental resistance, toxicity,
etc. The common MS orings are buna. I would use nothing else but
buna for my rebel brakes and hydraulics. I would consider viton to
be acceptable but more likely to leak at below freezing
temperatures.
Ken
Dick Wampach wrote:The type of fluid that you will be using is the critical question
that needs to be addressed
Vegetable based, such as used in most automotive applications.
Mineral based, such as most general aviation planes use (5606 red
in color) Synthetic, as used in the big systems (Skydraul, higher
combustion temperature) on the bigger airplanes.
Not all seals will hold up to all of the many types of fluids.
Dick
On Behalf Of Ken Sent: Thursday, November 25, 2010 3:39 AM Fw:
moose brake cylinders
I believe all these things use standard industrial O-rings.
Nothing special. Ken
Mike Davis wrote:
-----------------------------------------------------------------
List archives located at: https://mail.dcsol.com/login
username "rebel" password "builder"
Unsubscribe: rebel-builders-unsubscribe@dcsol.com
List administrator: mike.davis@dcsol.com
-----------------------------------------------------------------
