Date: Sat, 3 Aug 2002 21:45:33 -0500
Reply-To: Stan Wilder <wilden1@JUNO.COM>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Stan Wilder <wilden1@JUNO.COM>
Subject: Fire Investigation Type IV engine
Content-Type: text/plain; charset=us-ascii
I submit this information so folks with the 74-83 Air Cooled FI engines
might add the air distribution box to their checklist if you're smelling
fuel but not finding your fuel leaks at the injectors, lines or other
common locations.
I highly suspect that the combination of the tiny leak in the air
distribution box and the absence of the cold start fuel spray
distribution tree was the cause of this engine fire.
If you have a leak in the box it can be soldered by yourself or a
radiator shop.
*I recently had an opportunity to investigate an engine fire in a 1980
Vanagon Air Cooled.
It is hard to detect exactly where the engine fire started but here is
what I found.
#1) The cold start spray tree was missing from the air distribution
manifold and after the fire it appears to have a leak on the bottom of
the distribution manifold. Hard to tell if this leaking condition existed
before the fire. I've never seen an 80-83 Air Cooled distribution
manifold without this tree mounted under the cold start valve.
#2) The Magnesium fan shroud caught fire (tells me there was a lot of
heat) and once the magnesium ignited the fire department just backed off
the engine fire and tried to keep the fire inside the vehicle suppressed.
It is evident that the owner used at least one fire extinguisher on the
fire and that the fire department hit the burning magnesium shroud at
least once with water, blowing portions of it back up on top of the
engine and back into the engine tin both above and below the cylinders.
#3) The fire reached high enough temperatures to melt the engine fan, the
aluminum engine yoke, the oil cooler and when I removed the 17mm head
yoke mounting bolts the threads came with them. (everything rubber,
plastic or insulated with plastic just virtually evaporated leaving
clumps of ???, but nasty). The engine tin reached high enough
temperatures that it has sags in some locations.
#4) The valve cover gaskets were burned completely out of the covers.
#5) The aluminum sealing washer was melted from under the oil drain plug.
#6) Just generally speaking all of the steel fasteners had reached high
enough temperatures that they expanded substantially and enlarged the
threads where ever they were located on the engine, top, bottom etc. They
readily screw into the threads with just light touch of the fingers.
(tells me they'll never again stay tight)
#7) Surprisingly the exhaust studs also reached high enough temperatures
that they came out rather than the nuts coming off the studs. I thought
that these studs possibly reached red hot in normal use, I see now I was
wrong on that assumption.)
I'm not completely finished with the investigation, I have a few more
things to look at.
The engine is locked, It will not budge in either direction with a 24"
breaker bar.
I'm speculating the only salvage from this engine may be the crank and
rods. I have some question about the crank since the fan end got hot
enough to reduce the seal to a tin shell and a tiny spring.
Nasty work but very interesting to me because I've got a momentary fuel
smell everytime I start my Air Cooled Westy, think I'll check out my
Westy a little better tomorrow AM.
Stan Wilder
83 Air Cooled Westfalia
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