• Welcome to the new NAXJA Forum! If your password does not work, please use "Forgot your password?" link on the log-in page. Please feel free to reach out to [email protected] if we can provide any assistance.

Electric fuel pump ; why doesn't gas short itout?

my2monkeys

NAXJA Member
Stuppid question ,but why doesnt the fuel pump being immersed in fuel just short out between the pos. and neg. terminals ? Does gasoline conduct electricity?
 
Gasoline has a low electrical conductivity, but more importantly, all electrical connections are insulated from the gasoline.
 
....and did you know that its not a good thing to run your tank way low....believe it or not, the fuel also acts a coolant for your fuel pump. Who'd a thunk....lol
 
fizassist said:
Gasoline has a low electrical conductivity, but more importantly, all electrical connections are insulated from the gasoline.

actually not the clip on wire connections are all exposed inside of the tank. they are in the gas and fumes.

Fuel_Pump_out_of_tank.JPG
 
Gasoline liquid does not burn, it is the vapors that do.

We had a demonstration from the local fire department. The fireman actually put a match out in a cup of gas (he knew what he was doing).

So long as the connections are connected and there is no arcing all should be OK.
 
TJ Rat said:
Gasoline liquid does not burn, it is the vapors that do.

We had a demonstration from the local fire department. The fireman actually put a match out in a cup of gas (he knew what he was doing).

So long as the connections are connected and there is no arcing all should be OK.

Yep. Road flares will go out when kicked into a Diesel spill as well (had a cop who didn't know that while I was getting a roads incident under control. I was putting flares out, he told me that was a fuel spill, I said "I know - it's Diesel" and kicked a flare into it.)

As long as the electrical connections are tight (they're usually screws and ring lugs,) you'll be fine. You just don't want any sparking - especially with a low fuel level...
 
5-90 said:
Yep. Road flares will go out when kicked into a Diesel spill as well (had a cop who didn't know that while I was getting a roads incident under control. I was putting flares out, he told me that was a fuel spill, I said "I know - it's Diesel" and kicked a flare into it.)

As long as the electrical connections are tight (they're usually screws and ring lugs,) you'll be fine. You just don't want any sparking - especially with a low fuel level...

cherokee electrical connections are simple clips no screws. just press on connectors
 
The fuel pump & connections are submerged in fuel.
Simple, No Oxygen=No flame, I learned that while working on aircraft & noticed all the fuel pumps were in the fuel tanks!.
 
garr said:
The fuel pump & connections are submerged in fuel.
Simple, No Oxygen=No flame, I learned that while working on aircraft & noticed all the fuel pumps were in the fuel tanks!.

hello even when the tank is 3/4 full on an xj the connectors are above fuel line
 
rockwerks said:
cherokee electrical connections are simple clips no screws. just press on connectors

Not on my 90', they are most definetly ring connectors. And if you replace the stock pump with a non-OEM replacement make sure you modify the bracket so that the studs for the electrical connections do not short out against the pump bracket.
 
fizassist said:
Gasoline has a low electrical conductivity, but more importantly, all electrical connections are insulated from the gasoline.[/quote ] OK, thanks for the responses, so if I dunked the fuel pump in water and put 12 volts to it would it blow a fuse or work just fine? Also, if I put my head lite in the fuel tank and turned it on, what would happen? Thanks for your thoughts.
 
5-90 said:
Yep. Road flares will go out when kicked into a Diesel spill as well (had a cop who didn't know that while I was getting a roads incident under control. I was putting flares out, he told me that was a fuel spill, I said "I know - it's Diesel" and kicked a flare into it.)


I'd have paid to see the look on his face when you did that:laugh3:
 
bjoehandley said:
I'd have paid to see the look on his face when you did that:laugh3:

Priceless. My boss told me about it - I'd already turned around and gotten back to work. I understand his eyes were open about six inches, tho - and I think I heard his jaw hit the ground...

You know - cops need to know this sort of thing. Why aren't they taught it in the Academy?
 
Back
Top