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From: John De Armond
Subject: Re: burning a tire
Date: Sun, 03 Oct 1999 04:54:49 EDT
Newsgroups: rec.outdoors.rv-travel

"Light, Ed" wrote:
> Neon John <> wrote
> > Been there, done that, have the pictures :-)  Tossed a few tires on
> > a bonfire.  Neighbor called the cops.  Cops threatened the death
> > penalty unless I put it out.  Couple of squirts with the garden and
> > viola!  A pile of smoking gooey carbon.  Tires were easier to put
> > out than the bonfire. BFD.
> Thanks for the info. I wonder why some tire fires are so impossible.

Look at how many acres of them typically burn in a dump fire.  When
the fire is 10 or 20 layers down, it's kinda hard to get water on

> Is it your impression that the tire has to be completely smothered by the
> water? Maybe it's something a fire extinguisher can't do.

A fire is extinguished one of 3 ways:

1. remove the fuel - not an option in this case.
2. cool the fuel
3. deprive it of oxygen.

Any of the three will extinguish the fire.  The other consideration
is to cool the surroundings to the degree that rekindling is not
possible.  Water both cools and smothers the fire.  The steam
produced smothers fire not directly contacted by the water stream. 
Dry chem ONLY deprives the fire of oxygen by covering the fuel and
by decomposing and liberating CO2.  Ordinary dry chem is nothing
more than baking soda.  A more advanced extinguishing agent, Purple
K, is potassium carbonate, first cousin to washing soda.  it works
better on materials that are pyrophoric (tending to spontaneously
ignite in air) or reactive because it melts easier and flows over
the fuel.  

This is just a plain old Class A fire.  If you can get extinguishing
agent on it, it will go out.  QED.  Getting the agent on it in the
case of a small dry chem extinguisher might be a trick.  If I ever
thought I had any risk of a tire fire on my RV I'd arrange for a
water hose off the system's water system.  Water is probably the
best agent for this type fire.  Biggest problem is figuring out you
have a tire fire.  I once flagged down an 18 wheeler with a trailer
tire fire.  Driver didn't have a clue.  Fortunately it was a flatbed
or it would have burned down.

From: John De Armond
Subject: Re: burning a tire
Date: Mon, 04 Oct 1999 04:01:03 EDT
Newsgroups: rec.outdoors.rv-travel

"Light, Ed" wrote:
> So, John, what do you think of putting out a tire fire by smothering it
> with a blanket? Is that a myth or a good idea, if the fire extinguisher is
> inadequate?

Well if the tire was laying out flat on the ground and the blanket
was one of those GI heavy wool ones and I had nothing else.... 
OTOH, one of these modern poly blend blankets - I suspect it would
melt into a little ball of goo almost instantly.

I'm sitting here trying to visualize cuddling up with a burning
dually trying to tuck the blanket all around the tire so air can't
get in.  Hmmm...  If you kinda toss it over the top, well, you've
just added some fuel to the fire.

One of the things they hammer into you in fire school is to think
outside the box.  If a blanket is all you have, you use a blanket. 
Might not work but OTOH, if you do nothing....


From: John De Armond
Subject: Fires and Re: burning a tire
Date: Mon, 04 Oct 1999 18:08:02 EDT
Newsgroups: rec.outdoors.rv-travel

"Light, Ed" wrote:
> Neon John <> wrote in message
> >
> John, another question.
> Is there a fire extinuisher small enough to take along that's big enough to
> douse a tire fire? Or is it a case of you'd never cover it well enough?

I didn't mean to imply that the little extinguishers most of us
carry in our vehicles would be too small.  I don't know that.  The
problem would be since the small extinguishers lack a hose or a long
nozzle, getting close enough to get the agent on the burning tire,
particularly that part of the tire that is up under the cowling on
an RV, might be impossible.  The dry chem provides no cooling like a
water spray would and it discharges so fast that it would be
difficult to walk the stream into confined areas.  Dry chem
extinguishers will extinguish amazingly large fires for their size. 
If the powder adheres, it will probably put the fire out.  Getting
it on there will be a problem.  I don't use dry chem in my
restaurant.  They make too big a mess and there is no hose or
nozzle.  I use 20 lb CO-2 extinguishers.  These blow a cloud of
atomized dry ice at the fire.  It leaves no residue.   These are
probably too large for an RV.  Too bad.  They make really good beer
coolers too! Just put the can in the horn pointed at the sky and
squeeze.  Instant cold :-)

Speaking of fires, I saw a large class C burn down on I-75 today
near here.  Driver had enough warning that something was wrong -
probably electrical - that he had time to pull into a rest area. 
Burnt to the frame.  This brings up some more thoughts.

We all have lots of money invested in our RVs.  I wonder how many of
us have systems installed to manage the stored energy sources in our
vehicles.  I'm speaking now of the battery system and the engine and
fuel systems.  Some items:

* 	Central battery disconnect switches operable from outside the
RV.  This is standard hardware on a race car and the switches are
fairly cheap (<$50).  This switch can stop an electrical fire before
it gets started good.  I had the starter cable on my 68 Fury contact
the exhaust manifold once and burn through.  The large deep cycle
battery that I use in that car almost immediately lit the 2 gauge
wire red hot, exploding the insulation off of it.  All the time it
took me to get to the trunk, open the tool box and get a pair of
wire cutters the wire was glowing red hot!  That battery had a lot
of Oomph!  I was lucky the wire ran along the metal fender.  Had a
similar wire shorted under the dash, the car would have burned
before I could have gotten the battery disconnected.  That's the bad
thing about an electrical fire in a vehicle.  Until the battery is
either disconnected or dead, or the wire burns in two,  no matter
how many times you put it out, it rekindles by itself. I'd used
battery disconnects on my race cars for years but had never given it
a thought on my street vehicle until then.  Some may think it ugly
but mine stick right through the side of the front fender for anyone
to be able to operate.

*	Automatic fire suppression systems.  These are standard equipment
in race cars.  Consists of a bottle of Halon (yes still available
despite the EPA ban), some piping and nozzles and either a manual or
automatic (or both) release.  The nozzles are pointed at parts of
the engine where  a fire might start, at the fuel system and in the
case of a race car, at the driver.  A reasonable sized system can be
bought for under $500.  I have a system on order for my new used
Class C.  I think I'm going to install one in the generator
compartment.  Anyone who might think this is un-necessary might
consider how often most people leave the RV with the generator
running while they're doing something on a trip.  All that's needed
for a fire is a gas line to vibrate in two.

*	Heat/fire detectors interlocked with the RV's energy systems. 
Several years ago I wrote an article recommending that anyone with
an indoors washer and dryer should install a rate-of-rise fire
detector over the units and hook it up to dump power to the
appliances when tripped and then described how to do it.  The
article had been on the streets for only a few weeks when I got what
was probably the most gratifying letter I've ever received.  A
reader had followed my advice and less than a week after installing
the detector, his dryer had a lint fire while he was at work.  The
fire tripped the rate-of-rise detector (which alarms when the
temperature rises faster than 10 deg/minute) which shut off the
dryer.  His central alarm system alarmed and called the fire
department who came to find an already out fire and a lot of smoke. 
Both he and the fire department gave credit to this detector for
saving the guy's house.

These detectors are fairly cheap ($50-100 ea) and generate a contact
closure on rate of rise.  And because they are rate of rise
detectors, they don't trip when it simply gets hot.  We used these
detectors in the power house around turbines and large transformers
where the temperature was ordinarily very hot.  A simple relay feeds
signals to the various energy sources - stops the generator, cuts
off the LP, disconnects the batteries, etc.  This is going to go on
my new MH as soon as I get the time to finish the install.  Kiddie
makes the best detectors.

*	means of egress during a fire.  Anyone ever think of how they'd
get out of their RV if, say, the generator started a fire in the
middle of the night?  This is very close to home because I was
trapped in my burning home (not MH) about 10 years ago and barely
got out!  If you rationalize that you can figure something out on
the fly, you're fooling yourself!  For all their high prices, our
RVs are little more than mobile homes when it comes to fire.  These
things practically explode when the fire starts.  Think about how
you'd break out a window to escape if necessary, for example.

Oh, BTW, I'm not a fireman.  I'm aa retired nuclear engineer who
volunteered for various fire brigades over the years.  Legs were too
bad to let me play fireman for real :-(


From: John De Armond
Subject: Electrical fire
Date: Wed, 13 Oct 1999 20:21:30 EDT
Newsgroups: rec.outdoors.rv-travel

This is in the general category of "teach me to run my mouth"...

Last week I talked here about some precautions one can take to avoid
an electrical fire in an RV.  2 days ago I got to experience the
benefit of those precautions.  I had an electrical fire in my 68
Plymouth Fury.  Not a MH but the principle's the same.

I was driving down the interstate when I smelled something odd.  Not
really a burning smell but more like overheated chlorinated
solvent.  A few minutes later the dashboard erupted in smoke.  Tried
to turn the ignition switch off but it was frozen.  Locked 'er down,
skidded off the side of the road and was out of the car and was
hitting the battery disconnect switch before the car had quit
rolling.  After a few tense minutes with the fire extinguisher
waiting to see if anything had caught fire, the smoke cleared and I
could see what had happened.

The less-than-one-year-old ignition switch had started overheating. 
It relaxed the tension of the spade lug connector bringing power
from the battery.  This let the lug overheat which melted the nylon
connector.  This was the solvent smell. The hot wire drooped down
and laid across a ground wire. When the insulation melted, there was
a direct short from the battery to ground.  No fuse and on this old
car, no fusible link.  Had I not installed a battery disconnect
switch, this wire would have burned until it melted.  It would have
surely have set the cellulose-based sound deadening materials under
the dash on fire.  The battery wire was smoked all the way back to
the starter relay where it branched off from the battery lead.

I got some alligator clip jumpers I carry in my toolbox for
emergencies and jumpered power to the ignition, fuel pump and
alternator and drove home without problems.  A couple of hours spent
rewiring the battery circuit and replacing the ignition switch with
the old 30 year old one that was replaced because the key fit was
loose and the car was back to normal.


Install that battery disconnect switch.  If I was doing it over
again, I'd install one of the switches with a remote actuation cable
that could be operated nearer the cockpit.  Every second matters. 
The battery wire had melted its insulation.  It had started melting
through nylon tiedown clips that fastened it to the body at various
places.  When those burned through, the red hot wire would have
contacted flammable materials at several places.

Have that fire extinguisher handy where you can reach it from the
driver's seat.  Mine sits on the floor between the seat and the door
on the driver's side.  Consider a race car-style fire suppression
system.  My old Fury probably isn't worth it but my MH surely is.

Pay attention to odd odors.  I normally would have stopped to figure
out what the odor was but I'd just passed a bridge that was being
stripped and painted and assumed that the odor was paint solvent.  
Bad move.

Carry some electrical jumpers in your tool kit.  Mine are 3 feet
long and made from 14 ga wire and alligator clips.  I keep a half
dozen in the tool box.

Figure out how to get your vehicle running again if you suffer a
massive electrical failure.  It might not be practical for a fuel
injected engine but for a carburator engine, identify a place to
feed power to the ignition module, the electric fuel pump if
present, the alternator if it needs it, and to the starter.  This
can save a very expensive tow or roadside service bill.  More
importantly, it will allow you to drive the vehicle away from a
dangerous area.  I learned this lesson years ago when I was fooling
with British cars where electrical failure is a daily fact of life. 
(Sir Lucas, Prince of Darkness!) This wasn't the first time that my
little jumper kit has saved me a lot of hassles.


From: John De Armond
Subject: Re: Electrical fire
Date: Thu, 14 Oct 1999 04:07:06 EDT
Newsgroups: rec.outdoors.rv-travel

GBinNC wrote:
> On Wed, 13 Oct 1999 20:23:40 -0400, Neon John
> <> wrote:
> >Install that battery disconnect switch.  If I was doing it over
> >again, I'd install one of the switches with a remote actuation cable
> >that could be operated nearer the cockpit.
> Sounds like an outstanding idea, John. Where would one purchase such a
> device, or were you talking about fabricating it yourself?

This is a standard race car and heavy equipment part.  JEGS racing
parts ( has one listed for $19.95.  They've
gotten so whippy-kool with their java scripts and such that I can't
extract a URL to take you directly to the picture.  Click "products"
to the left, then "ignition & Batteries" and "Jegster Master
Disconnect Switch."  You'll see a picture.  A better switch can be
seen at  I've seen
these on heavy equipment.  This is another source for the same
switch that JEGS has:

One of my favorite companies for automotive wiring supplies is
Waytek.  800 328-2724.  They have a web page but it is still
inviting you to ask for a free 1998 catalog!  In the current
catalog, they have 2 full pages of battery disconnect switches.  The
basic switch, #44030 lists for $18.16.  This is the same switch as
you see at the JEGS site.  Switch #44031 includes an aux contact to
isolate the alternator circuit at the same time and lists for
$22.80.  Recommended, as shorted diodes in the alternator can cause
a fire.  

Cable-operated versions of this switch can be had from race car
supply outfits (can't lay my hands on a catalog at the moment) but
most guys just drill a hole in the switch handle and fit up a heater
control handle and flex cable.  Easy push-pull action.

Wherever the handle is located, a sticker bearing the standard
lightning bolt inside an upside-down triangle should be fitted. 
This is the standard marker in racing and (I think) aircraft and
most emergency responders are trained to know what the symbol
means.  The switch should come with a decal.

From: John De Armond
Subject: Re: Electrical fire
Date: Thu, 14 Oct 1999 17:35:13 EDT
Newsgroups: rec.outdoors.rv-travel

"Will R." wrote:
> >
> > When the insulation melted, there was
> >a direct short from the battery to ground.  No fuse and on this old
> >car, no fusible link.  Had I not installed a battery disconnect
> >switch, this wire would have burned until it melted.
> What happened to the orginal fuseable link?  If memory serves me this
> car had one.  It probably melted or corroded and got replaced with
> wire years ago.

Well, you see, It's like this. When you use an antique car as a
daily driver, you end up with a clip board with several sheets full
of to-do items.  Rewiring the engine compartment is on that list
:-)  The firewall terminal penetration had long ago started
failing.  the previous owner had put individual spade lugs on the
circuits that had failed.  I did that to the whole mess and sealed
it in some fireproof mastic a few years ago.  I imagine the fusible
link was part of that block.  Under the general theory of closing
the gate after the horse's gone, I just ordered some stuff from
Waytek including a breaker designed to replace the fusible link. 
fix that problem once and for all.  What we do for the vehicles we


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