Your right in that the wave washers don't have the force of the Belleville
washers but with the soft flanges on the aftermarket exhaust you don't have
the same conditions as the OEM anyway. Many manufacturers have different
approaches to this type of connection including shoulder bolts and actual
springs to allow the pipe to actually swivel and move while in use. There is
also the soft gasket (donut) option. Here the enemy is expansion of the
bolts when they heat up so toque those Belleville washer down so they still
can hold when the bolts grow.

Dennis

-----Original Message-----
From: Vanagon Mailing List [mailto:vanagon@gerry.vanagon.com] On Behalf Of
Mike B
Sent: Saturday, May 3, 2014 9:11 AM
To: vanagon@GERRY.VANAGON.COM
Subject: Re: 2.1 exhaust spring washers

Thanks for the info, Dennis.  I doubt that the wavy washers have anywhere
near the spring tension that belleville washers do, they're about half the
thickness, even once they all nest together in a stack.
I don't see the flanges deforming if the bolts are torqued just enough to
get a good seal and a light crush on the spring washer stack.  The same
amount of torque on a stack of wavy washers easily crush totally them flat,
which defeats the whole purpose of having some spring in the joint to allow
for some movement. I would torque the stack until its partially depressed,
leaving some space for spring-action, and not trying to compress the cups
completely flat.

Mike B.

On 5/3/2014 8:38 AM, Dennis Haynes wrote:
> The spring washers were cupped together in a short stack. A stack of
> the wave style lock washers will also work. The real problem here is
> the flanges on the j-pipe deforming causing the connection to become
loose.
>
> Dennis
>
>
> -----Original Message-----
> From: Vanagon Mailing List [mailto:vanagon@gerry.vanagon.com] On
> Behalf Of Mike B
> Sent: Friday, May 02, 2014 8:14 PM
> To: vanagon@GERRY.VANAGON.COM
> Subject: 2.1 exhaust spring washers
>
> Volks,
>     Does anyone have a picture or description of  how the 2.1 exhaust
> system donut gaskets hardware as it was originally installed?   I looked
> at the Bentley manual, and ETKA and found that the forward end of the
> connector pipe (where it meets the Y cast elbow) is supposed to have
> 65mm long bolts, 5 spring washers and 1 thick flat washer and a
> high-temp lock-nut.   The 5 spring washers are called diaphragm washers
> , also known as Belleville washers, which are basically cupped steel
> washers.   I need to know if the cups all nest together in a short stack
> or alternate against each other in a long stack.   The lock-nut
> obviously must have a specific torque and along with the spring
> washers, will this maintain a snug fit that can flex by use of a
> steady clamping force on the donuts and pipe flares.  The Bentley does
> not specify a torque value, so I'm assuming standard torque values.
>     I'm not interested in hearing how no-one ever does this and how
> yours has been just fine without the spring washers.
>     I'm looking for the correct information, so I can set mine up
> exactly the way that the factory engineered it.
>     I've experienced multiple joint failures due to them being
> assembled for years without these spring washers.  Now that I know why
> it's not lasting and have new parts, I want to do it right, as original.
>
> Thanks for any assistance.
> Mike B.