Date: Tue, 23 Sep 2008 18:36:02 -0700
Reply-To: neil N <musomuso@GMAIL.COM>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: neil N <musomuso@GMAIL.COM>
Subject: Re: Help with exhaust bracket design?
In-Reply-To: <2D9A51E2-A9B6-46F6-A083-C192B43D0553@eoni.com>
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Thanks Jim.
Darn those "bad vibrations"! Shakin' up those metal molecules (I
assume) Your 1" plate comment illustrates that more clearly now.
The exhaust is mounted entirely to the engine. I figured one metal
flex bellows http://tubaneil.googlepages.com/ExhaustBushin.jpg would
suffice. Obviously I missed the point.
I did not know about the isolators needed for the exhaust system.
Unless I misunderstood and you mean the isolators (DV setup) between
the engine carrier bars and frame. I used two Fox rubber mounts
between the engine and the carrier I made.
I didn't know the Vanagon exhaust had isolators. I'll study my Bentley.
Thanks for the pointer to that and the other tips.
Obviously I can't make it strong enough and need to make amends with
the exhaust Gods soon!
:^)
Thanks,
Neil.
On Tue, Sep 23, 2008 at 6:10 PM, Jim Arnott <jrasite@eoni.com> wrote:
> Neil,
>
> When I peeked under your van at Catherine Creek, I saw the potential for
> exactly what you're experiencing. The problem is the engine vibration. The
> solution is rubber vibration isolators. You need to develop a support system
> that has a bit of 'give' in it. You could do what you've done in 1" plate
> and all you'll have done is lengthened the time until it fails. Find someone
> local with a stock diesel vanagon. (Shawn Wright or Tobin Copley come to
> mind.)Take a look at the muffler mounting. You'll note that VW did mount the
> muffler to the motor (actually to the motor mounting system) and used
> elastomeric mounts. One on the right and two perpendicular to each other on
> the left. You'll need to come up with a similar system. I'll send you jpg
> of the relevant ETKA page p-mail. You might also chase down Bjorn Ratjen. He
> has a TDI mounted at 15 degrees and IIRC lives in Vancouver.
>
> Jim
>
> On Sep 23, 2008, at 5:29 PM, neil N wrote:
>
>> Hi all.
>>
>> After repairing my exhaust:
>>
>>
>> http://tubaneil.googlepages.com/JustForLaffs.jpg/JustForLaffs-full;init:.jpg
>>
>> (yes you can laugh now)
>>
>> I found yet more nagging details. Like broken exhaust brackets:
>>
>> http://tubaneil.googlepages.com/brokenexhaustbrackets
>>
>> I *think* the passenger side breaks are due to me bumping into a hill
>> side whilst escaping from a logging road on my last trip. The driver
>> side likely started to fail due to the increased motion. Plus upon
>> disassembly, I realized I had mistakenly built a little tension into
>> the design. i.e. inlet of cat needs to be pushed a little to line up
>> with the flange on primaries.
>>
>> So I'm hoping engine vibrations aren't the culprit.
>>
>> But if they are ......
>>
>> Does anyone have some pointers on a better design for these parts?
>>
>> I like where they're mounted, and the material should be suitable
>> (1/8" mild steel) but the design may be the fault here.
>>
>> FWIW, the welds held up fine. There is an flex bellows in the exhaust
>> system.
>>
>> TIA for any pointers or pics of successful designs!
>>
>
--
Neil Nicholson '81 JettaWesty "Jaco
http://groups.google.com/group/vanagons-with-vw-inline-4-cylinder-gas-engines
http://web.mac.com/tubaneil
http://tubaneil.googlepages.com/