Date: Sun, 23 Feb 2003 17:39:59 -0800
Reply-To: Alistair Bell <albell@UVIC.CA>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Alistair Bell <albell@UVIC.CA>
Subject: Re: vanagon with ticco engine/vibrations
In-Reply-To: <BA7EB3E1.C8B2%albell@uvic.ca>
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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
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