Date:         Fri, 12 Aug 2005 09:45:46 EDT
Reply-To:     THX0001@AOL.COM
Sender:       Vanagon Mailing List <vanagon@gerry.vanagon.com>
From:         George Goff <THX0001@AOL.COM>
Subject:      Re: Zombie Thread - Broken Stebro Muffler Bracket / Malcolm's
              trip + FIBER EXHAUST
Comments: To: RAlanen@aol.com
Content-Type: text/plain; charset="US-ASCII"

In a message dated 8/12/05 6:54:59 AM, RAlanen@AOL.COM writes:

<< the doughnut gasket joint in an exhaust system is used to allow placement
of the components so that there is no undue stress.  A solid flat joint allows
no repositioning of the components to the best position.  That said there are
two types of doughnut gaskets available on the market today.  Asbestos  fibre
ones and solid steel ones. >>

. . . and there are two distinct types of joints in which these doughnuts are
to be used.  Just because both seals are rings does not mean that they can be
interchanged, Frank, regardless of the bad advice you have given to your long
suffering customers.  Since you apparently do not recognize the difference,
I'll explain.

The bevels of the steel doughnut are made to seal to like beveled surfaces
formed by chamfers on the ID's of solid flanges or else by the flared ends of
exhaust pipes with "spin" flanges.  This joint has to be drawn together so
tightly that the spring bolt remedy suggested by Dennis would not be effective
because the springs would become bound long before bolt tension enough to seal the
joint was generated.

The fiber seal is meant to be used in a type of slip joint along with the
spring bolts.  One side of this joint is a solid flange set back from the end of
the pipe an amount equal to the depth of the ring.  The other side is flared
and has a loose flange.  In such an assembly the fiber ring is installed over
the protruding pipe end which protects the gasket from erosion ("burnout").

Shit, Frank, I only wish you had talked to me sooner . . . I could have saved
you and Stebro all those "many years of testing" and your customers all the
hardship they have endured.

George