Date: Mon, 5 Aug 2002 09:26:57 -0700
Reply-To: Jack <john.cook58@VERIZON.NET>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Jack <john.cook58@VERIZON.NET>
Subject: Re: Wiring warning: corrosion on AC main feed wire
In-Reply-To: <5.1.0.14.0.20020803222415.03b78620@unixguy.com>
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Rob,
Good catch! A fire was in the making for sure. This is what can and does
happen within people's walls at home.
Unfortunately, I think that solder tinning the wire (stranded?) and then
reheating after the crimp is not a good idea even though I'm sure you have
a good connection for now. It may intuitively seem a good thing to do,
but ...
A properly crimped connection relies upon the high metal/metal pressure to
maintain airtight connections and can do this better than solder. I think
you had a bad crimp to start with - that happens. Solder (usually a
tin/lead alloy) tends to cold flow away from the pressure points and may
then allow air to enter the connection (even without being reheated).
Also, I doubt the solder will wet the stainless steel. At least I've
never been able to solder to SS.
I'm not an expert in this particular technology although I worked close to
it. If I'm wrong, I'd appreciate someone correcting me.
//Jack
'85 GL
On 4 Aug 2002, at 20:39, Rob Scott wrote:
> I though that I'd post a note warning others to watch out for a
> potentially hazardous wiring condition I found today that some of you
> may also have.
>
> Yesterday I was going through my AC system electrical circuits after
> charging the system with ES-12 (problems with the charging hose sold
> to me by the ES-12 dealer but that's another story). I discovered that
> the main supply wire to the AC electrical system got hot, really HOT
> right at the junction block on the 50-amp solid metal fuse connection.
> This junction is located inside the rearmost portion of the storage
> cabinet on my 1990 Westie MV.
>
> The main feed wire is of good size (10ga?) but the crimped ring connector
> is what gets so hot. I suspect that corrosion and heat over time
> have raised the wire resistance in the joint. It gets so hot that the
> 50-amp metal fuse stamping appears to have been warped a bit and when
> hot the plastic insulation gets dangerously soft.The copper wire is
> discolored and has become quite stiff for approximately one inch below
> the connector.
>
> Today I removed the corroded wire and connector. I replaced it with a
> stainless steel high-temp ring crimp connector. I tinned the wire
> prior to crimping, and heated the wire until the solder flowed after
> I crimped the connector in place. Even when running the AC fans on
> high, the connector now gets no more than warm to the touch.
>
> Failure to correct this could have caused other wires in contact with
> the hot wire to burn through. Eventually the 50-amp fuse may have
> melted or the junction block may have melted. A short of
> the 10-gauge wire to ground (should it have melted) may even have shorted
> out an entire portion of the wiring harness.
>
> I suggest that anyone with AC check this junction at your earliest
> opportunity. Turn on your AC and let it run for a minute or two, then
> check the temp of the wiring junction where the main 10-gauge feed
> wire is screwed to the relay block.
>
>
> Regards,
> Rob
> p.s. Boy, have I learned a lot about AC in a short couple of days.
> Once I figured out where the wiring diagram for it was in Bentley,
> things were much easier.
>
> It's never too late to have a happy childhood.
> -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
> Rob Scott, mailto:rob@unixguy.com
> Langley, Washington on Whidbey Island (a suburb with a moat)
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