starting problem when hot

Jerry Clayton · #1 (**permalink**) 03-03-2009, 04:28 PM

Blas as you know I have been in aviation for many years----all modern jet airliners are bottom fueled to eliminate the static discharge associated with free fall fueling----

And this is after grounding the aircraft to ground rods thru the ramps, grounging the fuel trucks, and then grounding the truck to the aircraft--

Back to a car---a static charge will build up on your car driving along ( if fact, the lamans filler at high driving speeds can build up quite a charge from the air flow around it), now you stop for gas---your charge gets transferred to the pump, along comes another car, ditto, ditto again and again----then comes a tanker that got a big static charge filling up at the refinery after a tunderstorm, drove 600 miles to the station and goes to offload his fuel-----there has been enought differential charge built up to ignite the truck--- do you want to be there?????

Bond the filler to the tank----someday it could save your life

Blas · #2 (**permalink**) 03-03-2009, 05:37 PM

Then why are both my Mercedes not grounded at the fuel filler? I'll check the Passat tomorrow and the Porsche over the weekend...Take an ohm meter out to your car and check it....I'm not doubting what you are saying, just compiling the facts...I think you can make a compelling argument either way...I can't speak for airplanes or boats as I have no first hand knowledge on them. Guess we need to check a few more production.cars..Anyone with a Kirkham care to add to this discussion?

Wayne Maybury · #3 (**permalink**) 03-04-2009, 05:20 AM

Quote:

Originally Posted by Blas

Then why are both my Mercedes not grounded at the fuel filler? I'll check the Passat tomorrow and the Porsche over the weekend...

The gas filler caps on these cars are grounded assuming they have metal bodies. The gas inlet/filler is bolted to the body so there is no need for a separate ground wire. My Cobra has a fiber glass body, hence I grounded the filler cap to the metal frame. It may or may not be necessary but I figured, what the heck?

I have worked with flammable chemicals for over 40 years. All tank trucks must absolutely be properly grounded before loading or unloading to avoid the chance of a static spark igniting the product.

Wayne

Blas · #4 (**permalink**) 03-04-2009, 07:40 AM

Wayne,
When I take an ohm meter and connect one end to the car chassis and then touch the other end to the filler pipe there is no conductivity on either of my Mercedes. I then touch something else on the car and there is...No two ways about it? The gas caps are both plastic where you grab them, so you probably don't really connect electrically to the car when you remove it...Surely the TANK is grounded by way of its mounting to the car...

Blas · #5 (**permalink**) 03-04-2009, 10:04 AM

Interesting point: I called Fuelsafe and they did not appear to have a definitive answer either way on the grounding of the filler neck....

Ron61 · #6 (**permalink**) 03-04-2009, 10:13 AM

Blas,

On my 1965 Comet I can take the gas cap off, it is a locking one and some kind of metal, then touch my ohmmeter lead to the edge of the filler tube and the other to the chassis and I do get a reading. It could be via the tank straps that hold the tank in but when I looked under it I saw a wire that went off to the side and to a bolt on the frame. Don't know if that was stock or if it was added as I bought the car used. When it warms up enough I will go check on the 69 Cobra and see if is is grounded. As I said in my earlier post, I tend to err on the side of safety. To many grounds won't hurt.One to few could possible hurt.

Ron