SteveG

I'm not going to be paranoid about my my car b/c there have been fires in other sharks; I doubt it is any more at risk than any xx year old car out there; I'm going to keep checking my fuel lines and drive the car. But I want to know how to deal with fire if I can.

I want to know about FE, agents, installation, the whole thing. We know halon and halotron (sp) are the best but are bad for atmosphere, but the other chemical agents (cheaper) are a mess to clean up and some say not very effective. Although, banned after 2009, Safecraft website says it has Halon 1211 and 1301. Anybody purchased from them? I bought Halon from Stabile last Spring.

Re Engine fire and technique: If as Jeff (Speedtoys) says, you should never open the hood on a fire as it will surely flash, then the question is what good is an extinguisher in the cabin other than for something outside the bay? Bear w/me: Instinct says, if I have an extinguisher, I'm not going to watch it burn, I'm going to open the hood, is there a technique? Is Halon heavier than air? If the hood is cracked and I'm aiming the agent as best as possible toward the source is it not better to start the flow and try to force the air out of the bay suffocating the fire, while slowly (if possible) raising the hood?? The only other choice is a permantly mounted system. These run $450- 650 and up.

Unless Halon is lighter ? and you direct it under the bay so that it rises and pushes the oxygen out. I've never heard of this being done.

So we're back to the permanent system, with a nozzle somewhere under the hood, which is obviously the best sys to have, but $$$. And where is best to mount the nozzle?

jeff spahn

The systems I have seen have nozzles at the front and the rear of the bay. 4 nozzles. two front, two rear.

Alan

Halon is heavier than air, opening the hood is bad, not having a belly pan is bad, fans running or car moving means that all the halon will be out of the engine compartment in no time.

Halotron is the environmentally safer version of halon - but it doesn't work as well per volume.

There are plenty of thread on this - read those.

https://rennlist.com/forums/928-foru...gine-fire.html

https://rennlist.com/forums/928-foru...eferrerid=6055


Alan

dr bob

Halon is effective only if there's something to hold it at the base of the flame. It is heavy and will fall out the bottom of an open engine bay. So while it leaves the least mess it also has the risk of not doing the job. Fire travels on the hot vapors generated. In other words, something gets hot enough to give off flammable vapors, and the vapors burn. To kill an engine fire, you cut off oxygen, and also reduce the temp of the material so it stops giving off those vapors. Halon takes care of cutting off oxygen so combustion stops, and depends then on that loss of heat source to allow materials to cool. CO2, on the other hand, both smothers and cools, so it is generally a better option WRT actually putting the fire out. This applies to auto engine bay fires. Dry chemical extinguishers offer a bit of the benefits of CO2, plus they continue to generate a smothering blanket even after the extinguisher is spent. Except for the clean-up problem and the risk of corrosion when water is used to help the clean-up, a dry chem extinguisher probably offers the best chance of putting out an engine bay fire for the average user.

Technique for any of these is to put the extinguisher output as low as you can at the base of the flames, from a low as possible. Sweep the discharge from side to side, 'pushing' the combustion zone out from center until the flames are out. Trying to spray down on a flame means the gas and heat evolution from combustion is pushing your spray away from the place it's needed. Spraying low from the sides means those same rising heat and gasses will draw the spray in to where it will do some good.


If you have a fire--, TURN THE KEY OFF!!! Too many people jump out of a car at the first signs, and leave the engine running. This keeps pumping fuel to the engine bay until the engine dies. 30 Seconds of fuel-pump flow will make a fire bigger than most hand extinguishers can kill. Engine and fuel pump off, available fuel is what's in the accumulator and rails. With gasoline removed as the fuel source, you can use the garden hose to put the fire out safely. It cools the burning materials, and generated steam will continue to inhibit combustion.

Many modern cars now come with inertia switches that shut off power to the fuel system on impact. I had an interesting spring-and-ball-bearing switch on a race car 30+ years ago, where the pump ran off a switch in the dash with no "engine stopped" inhibit. Would not help in the case of a non-collision-caused fire, but an interesting piece. Meanwhile, OEM pieces from [pick your brand of SUV] might be an interesting add-on.

Leon Speed

For technique was learned to pop the hood, open it ever so slightly (a few cms) to get the nozzle of the fire extinguisher in and to get shot at the fire.

In case of an engine fire on our 928's, the old oil soaked hood liner is great for feeding the fire. Maybe it would be beneficial to put on a new hood liner, covered with a non-burning material. Don't know what material, just a thought that popped up.

pjg

Halotron in action, engine fire near the end: http://www.halotron.com/halotron_movie.php

SteveG

Thanks all. I should have mentioned, I would hope to be present enough to shut off engine, good to get that in the brain pan though; the scenario would be standing at driver's side with hood cracked a bit. In the best of this horrible situation, the belly pan holds the Halon long enough to fill the bay and out goes the fire. Then the question is how much vol of gas from a 2.5 lbs jug? and how fast does it drain through the vents in the pan?

Alan, didn't you have pics of a bottle w/hose to bay installed in your car? Or am I thinking of someone else?

Speedtoys

Thats half the battle, the other half is a man with a high volume hose spraying from the side of the hood..into any gap that is starting to open near the front of the hood..to suppress any rush of flame that is expected to come at the operator opening...the hood.

Its hard to open it slowly in bare hands and fancy nylon clothing, and live to tell about it, if it goes wrong.

andy-gts

do people use co2 extinguishers for the engine bay instead of halotron etc...???

Jim M.

Fire Extinguishers: advantages/disadvantages by brand and chemical.
Halon 1211: Advantage: leaves no residue, effective, not thermal shocking. Disadvantage: it’s toxic, doesn’t quench the fire and depletes ozone. Used in hand held fire extinguishers because it’s toxic. One of two chemicals used by FireBottle.
CEA-614: a Halon substitute. Advantage: leaves no residue, not thermal shocking, and ozone safe. Disadvantage: it doesn’t quench the fire and it takes twice as much to do the same job as Halon, it’s also expensive. 5 lbs. of this is SCCA legal, but it won’t do the same job as 5 lbs. of Halon.
AFFF or ColdFire: are foaming water-based systems. Advantage: it quenches the fire. Disadvantage: the systems are heavy, large, may thermal shock, will not spread out like Halon, leaves a mess in the car and on the track and it’s expensive.
Halon 1301: the best product on the market. Advantage: it’s effective, non-toxic, non-caustic, leaves no residue, small, lightweight, industry standard with plenty of supply, no thermal shock, leaves no mess. Disadvantage: it does not quench the fire and it’s ozone depleting. There are two major suppliers of Halon 1301: Phoenix and SafeCraft (RaceSafe). Halon 1301 is stockpiled across the country. It’s readily available, and should be around for at another 10+ years. The manufacture of this chemical has been banned by international treaty but the use hasn’t.

I've had to use my fire extinguisher twice, once on my own car. Worth 10X what I paid for it.

Speedtoys

(Most of this is Cut & Paste from appropriate club CCRs to be specific)

=====
They must be Halon 1301, 1211, or Halotron I, hexafluoropropane, HFC-236a, CC0610, FE-36.

2lbs min for bottles
5lbs min for systems

AFFF material (e.g. SPA Lite, ZERO 2000, Coldfire 302) 2.25 liter minimum...with the PROPER nozzles.

Onboard systems may also use CEA614 provided that the lines and nozzles are replaced as per the manufacturer’s (3M) instructions.
=====

If yer system doesn't match these requirements, its not what I would consider safe enough for street use, because its not meeting race requirements...and insurance reasons/best-practices are what generally defines safety regs.

bordin34

I had a fuel fire in one of my cars, 73 Charger. The rubber fuel line leaked onto the distributor and caught fire. The car stalled at the stop sign and I saw smoke coming from my hood so I grabbed my dry chem extinguisher, which is in reach of the driver, and popped the hood. When I popped it, flames were licking off the tip of the hood, luckily my extinguisher managed to put it out but just barely.
This engine had a mechanical fuel pump so no fuel flow after the engine stalled.
You can see the extinguisher I used in the pics.


Luckily I hosed off all the powder before it had time to corrode. All I had to replace was the fuel line and 3 wires.

danglerb

Does steam displace oxygen?

If so maybe a system that sprayed coolant on the engine and headers with the hood closed would put out a fire? Could be powered with a can of nitrogen, maybe with some scheme to add a foaming agent.

I'm thinking a BIG factor in addition to old hoses are engines coated in oil, and our pressurized fuel lines that don't dump when the pump is turned off, maybe get rid of the check valves.

OGRacing

Nice car.
Are you still finding powder in the engine compartment? It seems like it never goes away completely.

Bill

bordin34

I haven't seen any powder since the day I hosed it out. But when I hosed it out I sprayed the water everywhere assuming everything under the hood was a loss, so the entire engine bay got drenched. I even sprayed the electronics and connectors.
My fire was burning maybe 30 seconds and I believe the lower pressures of a carbureted system made it burn shorter than if it were fuel injected.