• Welcome to the new B.I.R.D. Forum. Please be sure to read the "New Member / New Registered ? Please Read" thread in the Coffee Shop. This contains some important information. To become a full member ( £5.90 a year ) simply click on your user name near the top on the right I hope you enjoy the new site ................ Jaws ( John )

Explosion

mick the knife

Registered User
Too a lot of techie peeps on here this will prolly sound a stuppit question, but why doesn’t the petrol tank go bang when there’s live electrics inside the tank ??
 

derek kelly

The Deli lama
Club Sponsor
Not a techie so I don’t know.
Now I do.

All cars have the same "design" fuel pump (a small motor turning a device - usually a turbine or gerotor). ... The reason electric, tank- mounted fuel pumps do not cause explosions is that the concentration of fuel vapors is too high to allow an explosive mixture.
 

mick the knife

Registered User
Now I do.

All cars have the same "design" fuel pump (a small motor turning a device - usually a turbine or gerotor). ... The reason electric, tank- mounted fuel pumps do not cause explosions is that the concentration of fuel vapors is too high to allow an explosive mixture.
Wow
Never would have believed it
 

Centaur

Site Pedant
Club Sponsor
Now I do.

All cars have the same "design" fuel pump (a small motor turning a device - usually a turbine or gerotor). ... The reason electric, tank- mounted fuel pumps do not cause explosions is that the concentration of fuel vapors is too high to allow an explosive mixture.
Also, and probably more importantly, they are brushless motors which means no sparks.
 

Squag1

Can't remember....
Club Sponsor
Well its "under water" most of the time:D

Can't remember the Bird, although I did have one out, but the connections for the pump in the BMW are inside the tank.
It's aluminium, which I remembered after I ordered a magnetic tank bag.:mad:
 

Lee337

Confused Poster
Club Sponsor
My Tiger has the fuel pump inside the tank, often wondered the same, how does an electric motor work immersed in fuel & why doesn't it go bang? :yikes:
 

Pow-Lo

Make civil the mind, make savage the body.
Club Sponsor
Now I do.

All cars have the same "design" fuel pump (a small motor turning a device - usually a turbine or gerotor). ... The reason electric, tank- mounted fuel pumps do not cause explosions is that the concentration of fuel vapors is too high to allow an explosive mixture.
Now, you've done it, now you've really done it!

We'll have Beaker back here demanding to know if it's safe to smoke a fag inside a petrol tank. It'll take Tony slim63 about a week to explain it to him and he'll still ask if it's safe :BangHead::BangHead::BangHead:
 

slim63

Never surrender
Club Sponsor
Too a lot of techie peeps on here this will prolly sound a stuppit question, but why doesn’t the petrol tank go bang when there’s live electrics inside the tank ??
Easy really you need oxygen, fuel (vapor) & a spark (or ignition source such as a flame) to get fire, contain the fire & it becomes an explosion

So while fuel & electrics are present in your tank there is no spark just a small current & there is no vapor mixed with oxygen present at the pump or fuel gauge = no bang

On a related point I have had people running for cover when I have welded tanks, but its perfectly safe done properly IE stick a hose from a car or bike exhaust into the tank, wait a while then weld away the co2 from the exhaust removes the oxygen so with one of the required components gone there is no bang
 

DEG5Y

Been there, and had one
Club Sponsor
Yep, same as gas, has to be the correct gas/air mix otherwise it won't burn!
 

Malone

Been there, and had one
Club Sponsor
An old disused fuel tank that hasn’t seen fuel in ages will still provide a big bang if you don’t look out.
 
Top