Date: Fri, 28 May 2010 10:52:06 -0500
Reply-To: John Rodgers <inua@CHARTER.NET>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: John Rodgers <inua@CHARTER.NET>
Subject: Re: 2.1l Spark plug wire routing
In-Reply-To: <4BFF582B.6040009@williamsitconsulting.com>
Content-Type: text/plain; charset=ISO-8859-1; format=flowed
Keep in mind that the voltage in the ignition wires is about 25,000
volts. That represents a lot of electrical pressure trying to get
electrons to leave the wires any way they can. Of course the normal way
is down through the wire itself to the spark plug - BUT - there is a
moment in time when the pressure builds to the point where the pressure
is great enough to jump the gap in the spark plug. In that time just
before the spark - if there is any weakness at all in the insulation,
the electrons will seek out that weakness and attempt to arc from that
point. Adjacent wiring such as another plug wire actually in contact
with another wire sets up a condition which makes it easy for the jump
to occur. Once it starts - that will be a weak spot forever in the
insulation. It doesn't require a great deal of separation between the
wires, but some space ensures a reduced possibilities of a short.
John Rodgers
Clayartist and Moldmaker
88'GL VW Bus Driver
Chelsea, AL
Http://www.moldhaus.com
On 5/28/2010 12:44 AM, Steve Williams wrote:
> Hi,
>
> I have a 91 Westfalia, standard, 2.1l. I have just started to do the
> work on it myself after having work done by a mechanic for the last
> couple of years. My work has slowed down to a point where I can do
> things myself and take the "right".
>
> I have started with things that I'm familiar with from days of old,
> though this is my first fuel injected vehicle I've worked on. So, I
> started with rotor, distributor cap, plug wires and spark plugs. I
> wanted to know the "vintage" of that system and in the grand scheme of
> things it's not that expensive.
>
> I routed the new spark plug wires where the previous ones went. After
> it was all tie wrapped, I noticed the plug set came with directions, so
> out of curioisity, I actually read them! lol It says to keep the spark
> plug wires separated as far as possible, and if they do need to cross,
> it should be at 90 degrees. Well, the spark plug route that I followed
> for the passenger side cyclinders doesn't conform to that policy! I've
> driven this van with wires like that for 3 years now... how important
> is this "guideline". It makes sense from an inductive interference
> point of view...
>
> Where would the plug wires normally be routed?
>
> I've got a photo of the setup here:
>
> http://www.williamsitconsulting.com/westy/DSCN2355.JPG
>
> And yes, the fuel lines are next... but I'm curious if these are "stock"
> VW fuel lines with the grey protection on them?
>
> Thanks,
> Steve Williams
>
>
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