Flame arrestor?
 

What is the theory behind the screen in filler neck of model A gas tank being a flame arrestor? I can’t figure this one out. To keep the gasoline attendant from dropping his cigarette down there?

Re: Flame arrestor?
 

To keep fumes in the Gas Tank from explosion if a static charge gets built up on the nozzle and it sparks/grounds when you touch the gas tank opening.

Re: Flame arrestor?
 

How does that work?

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It has something to do with airflow and the fumes not getting past the arrestor. I think I read about it a while ago on here.

Re: Flame arrestor?
 

I think if it catches on fire there is just a flame like a barbecue grill since it is letting vapor out to burn but not letting fire down into the tank where it would go off like a bomb. You might have to repaint the visor if it catches on fire unless of course you have a slant windshield model. Either way it will be spectacular!

Re: Flame arrestor?
 

In the Model A production era gas pumps were more primitive and the hose nozzles were usually not grounded. Putting the nozzle in the tank could create a spark, hence the arrester was needed. Think about the antique gas pumps you may have seen owned by a hobbyist.

Re: Flame arrestor?
 

The flame will not pass through the screen. Ask any Coal Minor from the days of lanterns in mines.

Re: Flame arrestor?
 

>>What is the theory behind the screen in filler neck of model A gas tank being a flame arrestor? I can’t figure this one out.


It is used by the salesman to calm nervous passengers while they stare at the fuel tank, and especially if there is a leak onto the passengers foot and they are smoking.

Re: Flame arrestor?
 

I agree with barnstuff. Modern nozzles are grounded to prevent static electricity.

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I assumed it was to strain crappy fuel from the 30’s , too simple I guess

Re: Flame arrestor?
 

It works on the same principle as the miners Davey lamp, invented by Humphry Davy. The metal gauze conducts the heat of any external flame or spark away so that the fuel on the inside of the arrestor cannot heat up and ignite. The Davy Lamp worked in reverse, preventing the burning wick inside the lamp's mesh screen from igniting the methane "fire damp" gas outside in the coal mine.
That's what I think. And why I use rhem. I do remove it while filling the tank because it impedes flow. I replace it before driving away, in case of a collision or carburettor fire etc.
Any other opinions?
SAJ in NZ











a

Re: Flame arrestor?
 

SAJ and Daren007 have it right

Re: Flame arrestor?
 

I wouldn't assume that all commercial fuel pumps are grounded. In aviation, we ground the pump or fueling truck to the aircraft before we start fueling. You never see folks do this at a gas station. The little metal nozzle with the spring loaded flap acts as a spark arrester in the modern tanks.

That filter/spark arrester should be in the tank when fueling or it defeats the purpose.

Re: Flame arrestor?
 

I read an article the other day that stated 'most' fires at gas stations are caused after the pump shuts off. It appears women get back in their car after starting the pump and fail to ground themselves again before they touch the nozzle. The article goes on to say that this does not happen as often to men because men don't get back into their cars while gassing up.

The bottom line is ground yourself before touhinhg the nozzle.

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Additionally the A is not grounded to earth ground, 4 tires prevent it from being earth grounded.

Re: Flame arrestor?
 

Pumps here in WA State all have warning decals on them.

Re: Flame arrestor?
 

Very few people seem to recall HS physics that tell us that there is a natural law that flames can't go through a screen (At least a fine one anyway) This law has a name but I forgot it. This law is demonstrated with Coleman lamps and certain propane heaters.
Terry

Re: Flame arrestor?
 

Re: Flame arrestor?
 

I believe everyone on what they are saying spark resistor and filtering. The question I have is how many people still have them in the gas tanks? :confused:I still have mine in the tank

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Mu truck had an arrestor that was held in via tabs instead of the screw in style. After it dropped into the tank when I pressed down too hard and having difficulty getting the arrestor out of the tank, decided not to replace it. And with the spark arrester in it took forever to fill the tank.


I am careful to touch me and the gas nozzle to the headlamp shell before putting the nozzle into the tank.