Date: Sun, 29 Jun 2014 19:29:01 -0400
Reply-To: David Beierl <dbeierl@ATTGLOBAL.NET>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: David Beierl <dbeierl@ATTGLOBAL.NET>
Subject: Re: Metallic burning smell front of van.
In-Reply-To: <20140629200305.CD0E823B1C@pb-smtp0.pobox.com>
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At 04:03 PM 6/29/2014, Harry Hoffman wrote:
>this is pertinent but I'd like to solve it). Get to driving a bit,
>on a hot day, and all of the sudden I'm smelling what I can only
>describe as a metallic burning smell. Not unlike that same sort of
>smell that is produced in a car fire. Stop and look everything over.
>Temp is reading its normal mid point, there's plenty of coolant in
>the reservoir tank. The temp light works on startup by
Hmm, things that can burn.
Electrical wiring and electronics - burnt vinyl, styrene, epoxy,
phenolic, all fairly distinctive smells of varying chemical
character. See http://boedeker.com/burntest.htm and
http://www.modernplastics.com/how_to_identify_plastics.htm sor some
thoughts on how burning different plastics smell. If you've smelt an
overheated or burning paper-phenolic circuit board (used to be
common, they're tan or dark brown. Glass-epoxy is more common now
and are usually colored with a green mask) or have ever smelled
carbolic acid/phenol that's what burning phenolic plastic smells
like. If you've ever been near an integrated circuit when it smokes,
that's what epoxy smells like. The big connector block in the back
of the fuse/relay panel might be phenolic, not sure. If it isn't,
it's might be nylon but perhaps a mixture with styrene and maybe ABS
in it? Styrene is what model airplanes and little clear hinged boxes
are made of, burn with a very distinctive sharp smell. The bodies of
the various dash/ignition switches are some sort of
thermoplastic. If the heater motor seizes and burns most of what
burns is probably the varnish on the wires of the motor armature,
which are probably phenolic - maybe accompanied by burning vinyl
smell from wiring or perhaps the switch body.
Headlight sockets are very likely phenolic plastic as it doesn't melt
if overheated. They're a ripe candidate for getting too hot and smelling.
All terminals and connectors carrying high current are prone to
melting/burning.
Brake and clutch linings/pads - probably a strong phenolic
odor. Sometimes you can smell it when a big truck goes by.
Hot coolant from inside cooling system - sweet/metallic/rubbery
smell, very distinctive. No idea what clean hot coolant smells like
except for the sweet part -- it's closely related to glycerin which
is also sweet.
Hot wheel bearing could sizzle the grease and give a burning-oil smell.
Oil leak onto exhaust pipe, burning oil.
Coolant onto exhaust pipe, hot coolant.
Brake fluid - dunno, but the regular type is a sort of alcohol and
I'd suspect a chemical smell.
Rubber hoses, tires etc - burning rubber.
What are the burning things you know it does *not* smell like?
Yrs,
David
