Date:         Thu, 26 May 2005 11:52:07 -0600
Reply-To:     jimt <camper@TACTICAL-BUS.INFO>
Sender:       Vanagon Mailing List <vanagon@gerry.vanagon.com>
From:         jimt <camper@TACTICAL-BUS.INFO>
Subject:      Re: Fuel Lines...my turn! And a replacement question.
In-Reply-To:  <010201c5619b$57772b60$677ba8c0@MAIN>
Content-type: text/plain; charset="US-ASCII"

This is documented in many tech sites covering the newer fuel blends.  There
are critical points to be reached though.  Rubber made before the blended
formulations with methyl alcohol or mtbe formulations and oxidized fuels,
will age much faster. The higher the alcohol content the more the rubber
formula has to change to account for it.  In modern fuel lines this is
usually done by "layering" the hose.  Inner hose that will withstand the
alcohol then wrapped with a reinforcing layer and then a rubber that can
take the abuse of the heat and vibration of the engine bay.  This is why you
will find that the hose that you use for a immersed fuel pump is not a
standard fuel line and is much pricier.

On standard fuel lines in use today the E5 to E10 currently in use are not
found to be harmful to cars after 1985 according to a california air/fuels
study group.  Cars prior to 1985 may need plastic and rubber fittings and
gaskets in the fuel system replaced with newer formulations.

A study done by VW for the brazilian GVT found that around E50 a vehicles
rubber lines deteriorated rapidly and that stainless was needed for the tank
and all lines with rubber only for connection points.  A canadian fuel
refiner doing research on alcohol fuels found that injectors were another
weak point.  Depending on the mfr and style the plastic seals and internals
were corroded away at almost double normal wear.

Because of the steady climb in alcohol percentages (E15 to E17) projected as
a normal fuel in just a couple years, many fuel systems in current mfr cars
are built with stainless lines and tanks.

A note that came up on a site about 3 months ago was that some mfr (and
members of this group) have lined their tanks with material incompatible
with alcohol.  POR15 has reformulated their tank sealant to make it more
alcohol resistant.

Some good basic E85 info
http://www.eere.energy.gov/afdc/e85toolkit/converting.html

jimt

On 5/25/05 8:33 PM, "Robert Fisher" <refisher@MCHSI.COM> wrote:

> Several people have posted concerns that the old rubber formulations can't
> hold up to or aren't compatible with the additives and such in modern fuel.
> It would be interesting to see some facts about this, but for the meantime
> it might be well to keep the possibility in mind.
>
> Cya,
> Robert
>