Date: Thu, 12 Aug 2004 09:15:15 -0700
Reply-To: Jim Thompson <jim@KARMANNGHIA.COM>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Jim Thompson <jim@KARMANNGHIA.COM>
Subject: Re: exhaust nuts
Content-Type: text/plain; charset="iso-8859-1"
This style of nut has been in constant use on VW exhaust systems since the
25hp air cooled days and when I can find them I use them because they work.
Still available from the dealer as 311 101 463 (M8, 13mm hex). This type
you describe has never to the best of my experience and knowledge been
available through metric fastener vendors when I had the parts biz running,
I had to get them from the dealer (usually special order). An acceptable
alternative is a "Fuji Lock" 8mm nut, which I currently use on my 84 Westy.
There are tiny metal tabs on one side of the nut that when torqued down
would lock the nut in place to the threads. When loosening the nut, the
tabs would usually bend or break apart, rendering it's locking capabilities
useless. These are not easy to find as well from the local parts stores
either, I just happened to have a bag of them in my stash from my biz days.
The reason for either style nut being made the way they are is to lock them
in place so they don't come loose. If you use regular 8mm nuts with split
or wavy lockwashers, the heat virtually desintegrates the washers, thus
making loose nuts (apropose [sic?] for the VW world in general I think :-)
The regular 8mm nut is VW N01100818
Jim Thompson
84 Westfalia 2.1 "Ole Putt"
oldvolkshome@earthlink.net
jim@karmannghia.com
http://www.oldvolkshome.com
***********************
----- Original Message -----
From: "Jonathan Farrugia" <jfarrugi@UMICH.EDU>
To: <vanagon@GERRY.VANAGON.COM>
Sent: Thursday, August 12, 2004 3:20 AM
Subject: exhaust nuts
> so a week or so ago i had the chance to take apart a 1.9 wasserboxer
> exhaust with the factory exhaust system on it. or i assume it was since
> the van is from arizona. anyhow the exhaust nuts mounting the headers to
> the heads were unlike any that i have seen before. they are 13mm nuts
> with what look like wound spring steel inserts inside them. similar to
> what a helicoil looks like. if these are factory nuts are they still
> available at the dealer or would the dealer hand me some regular nuts with
> a N part number? additionally does anyone know why these nuts were made
> like this? i would guess something to do with the thermal expansion
> differences between the aluminum head and the steel of the header and
> stud.
>
> jonathan
