Cobra Make, Engine: ERA #732, 428FE (447 CID), TKO600, Solid Flat Tappet Cam, Tons of Aluminum
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Quote:
Originally Posted by cobrakiwi
I got into this very discussion about this point with a friend, can you give me your reason / reasons why you need a ground strap?
Thanks.
Same reason you do it on a boat (and there are regs for boats but I don't think there are for cars!). If you have a build up of static electricity, from the gas flowing in to the tank, and you don't have a path from the tank filler to the ground circuit of the car, and the stars align properly, then you can get a nasty spark, which you don't want. The general rule for boats is that a metal fuel fill system and metal fuel tank have to have less than 1 ohm resistance to the system ground. But, if you're feeling lucky, feel free to disregard this.
Cobra Make, Engine: ERA #732, 428FE (447 CID), TKO600, Solid Flat Tappet Cam, Tons of Aluminum
Posts: 22,005
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... so let's go to the videotape. In this vid, the woman created the buildup of static electricity by getting back in to her car, maybe shuffling her butt around a bit, and with just the right fabrics involved, like wool pants, and then she touches the metal gas pump. On a non-grounded fuel inlet system, the rushing fuel itself can create the build up of electrons, and when the build up reaches the magic point, the electrons will jump. If the fuel inlet system is bonded to ground, the electrons instead will slowly dissipate through the system. And this is why you should never get back in your car and wait for the pump to click off.
An interesting and timely topic. My driving season came to an end before I was fully prepared. I had about 10 gallons of 93 octane fuel with Ethanol in the tank. No gas treatment or Marvel oil either. I decided to buy the pump for my Flo Fast cans. I went and purchased 7.5 gallons of 110 Octane Cam2 fuel. When I got home, I used the pump to siphon out 7.5 gallons of the regular fuel from the Cobra which I treated and will use for my snowblower, generator, etc. I then used the pump to put the 7.5 gallons of treated 110 octane fuel back in the Cobra. I read lots of warnings about static electricity before using the pump. I did use the ground wire and connected it to the Lemans cap flange, but I was definitely wondering how well that flange was grounded. I am hoping the aluminum body helped a bit. Anyway, I did not blow up but was a bit nervous.
Cobra Make, Engine: ERA #732, 428FE (447 CID), TKO600, Solid Flat Tappet Cam, Tons of Aluminum
Posts: 22,005
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Quote:
Originally Posted by Mongoose930
I read lots of warnings about static electricity before using the pump. I did use the ground wire and connected it to the Lemans cap flange, but I was definitely wondering how well that flange was grounded. I am hoping the aluminum body helped a bit. Anyway, I did not blow up but was a bit nervous.
Holding the lit Lucky Strike behind your back while you pumped definitely helped.
What did all the original csx 3k cars do with there filler caps as far as ground straps go?
Any of you original car owners out there have an answer to this one?
Thanks.
Cobra Make, Engine: ERA #732, 428FE (447 CID), TKO600, Solid Flat Tappet Cam, Tons of Aluminum
Posts: 22,005
Not Ranked
Quote:
Originally Posted by cobrakiwi
What did all the original csx 3k cars do with there filler caps as far as ground straps go?
Any of you original car owners out there have an answer to this one?
Thanks.
All the original fiberglass cars had them. Seriously, if the metal fuel inlet portion is securely fastened to an aluminum body, and the fuel tank itself is securely fastened to the frame via a conductor like aluminum and not leather straps, then the resistance of both those components are almost certain to be less than one ohm to the system ground. Glass cars like my ERA require a little more care.