YES!  I had not read your post when I sent mine off to the list.  I tell you
I am soo excited to have found the problem.  when my brother started up the
engine without the belts, and no buzzing, or vibration was occuring, I was
practically, no I was, jumping up and down!    That is, after I exited the
van!  : )

Julianna

----- Original Message -----
From: "Alistair Bell" <albell@UVIC.CA>
To: <vanagon@GERRY.VANAGON.COM>
Sent: Sunday, February 23, 2003 5:39 PM
Subject: Re: vanagon with ticco engine/vibrations

> if I may, here is Gary Stearn's posting of a year or so ago.
>
> Alistair
>
> Our TiiCo installation was one of those that was burdened a major droning
> resonance in the interior at about 3800 rpm.  I drove myself crazy trying
to
> eliminate this. Nearly all of my efforts were targeted toward the exhaust
> system.  Now I realize that the exhaust vibration was an effect, not a
> cause.  Last week, the droning suddenly stopped on it's own.  Totally
gone.
> Smooth constant sound all the way up the tach.  A day later I discovered
> that the bracket that maintains belt tension on the alternator had
> fractured.  Though broken, nothing fell away and it still kept the belt
> tension by keeping pressure on the broken spot.  I noticed the break,
> removed it, and welded it up. The droning vibes came back big time. I
> remembered reading that many automakers have ended up revising alternator,
> A/C and other accessory mounts to eliminate noise, vibration and harshness
> (NVH) in 4 cylinder engines.  Oh my god, I found it.
>
> The solution came in the form of one of the rubber bushing mounts intended
> to mount the exhaust brackets in the TiiCo installation.  After alot of
> experimentation I decided that the one on the muffler side was making the
> droning worse, so I left it out. Now, I used it to separate left and right
> sides of a fabricated alternator tensioning bracket.  It's been installed
> for about a week, the droning has not returned, and it seems to do a good
> job of maintaining belt tension.
>
> The fact that not all TiiCo engines seem to have this problem surely
relates
> to the variety of belts and brackets that mount the accessories.  Some
have
> A/C, some don't.  Some use one long serpentine belt for most of the
pullies,
> some don't.
>
> If you have the TiiCo droning, test this theory by removing the tensioning
> bracket and the belt from the alternator (yes the charging light will come
> on) and take a test drive.  I'm betting it will be the quietest ride in
your
> TiiCo powered Vanagon that you've ever had.
>
> Gary
>