Date:         Mon, 4 Apr 2005 10:34:01 -0400
Reply-To:     Kim Brennan <kimbrennan@MAC.COM>
Sender:       Vanagon Mailing List <vanagon@gerry.vanagon.com>
From:         Kim Brennan <kimbrennan@MAC.COM>
Subject:      Re: why...vibration @ idle only when skidplate is installed --
              turbodiesel engine
Comments: To: BenT Syncro <syncro@GMAIL.COM>
In-Reply-To:  <ccafde090504040327572b4077@mail.gmail.com>
Content-Type: text/plain; charset=US-ASCII; format=flowed

Which portion of the skid plate, Ben? That around the engine, that
between the front and rear diffs? Or the front section? (note to
non-Doka owners, the front section is different than the tire carrier
typically found on passenger Vanagons, it really is a skid plate....

The section between the transmissions would lead me to think that the
vibration was in the drive shaft, but if you were just sitting still
that shouldn't be the issue.

The rear section is just tying the engine carrier to the middle
section. If that's heavily vibrating when connected, the vibration is
still there when not connected, it just isn't getting transmitted all
the way forward.

That would mean engine mounts might need to be examined.


On Apr 4, 2005, at 6:27 AM, BenT Syncro wrote:

> Hi Folks,
>
> I have a 1989 Syncro 16 doka. When I had the 1.6td in there, I noticed
> it vibrated like crazy at idle. The vibration is so severe that it
> shakes the instrument cluster to the point where it looks like it will
> all fall apart. If you raise the RPMS, she smooths out.
>
> I initially blamed this all on an old tired engine. When I had a 1.9td
> AAZ motor installed, the vibration miraculously disappeared. So it
> seemed at first. Then we put the skidplate back on. Bam! She was
> vibrating like a marital aid gone insane again. Same symptoms as
> before. Take the skids off and all is well again. Checked for contact.
> Nothing out of the ordinary. Everything bolts on where the factory
> designed them to be or so it seems.
>
> Is anyone else out there experiencing this with their turbodiesels? It
> appears obvious that the skidplate is transferring the vibration
> forward. I can't see getting around this unless I . Can anyone help?
> Or am I stuck keeping my foot on the throttle? BTW, my skidbars
> actually have a big plate welded to it unlike the ones you see in the
> gas powered Syncros. The truck is also equipped with the noise
> protection capsule which is a series of sheet metal plates that form a
> box around the engine. Removing that shrouding does not seem to affect
> the vibration -- just increases noise.
>
> tia,
> BenT