Well after years of owning my 72 demon and driving it only a few hundred miles I finally went out and fixed my broken gas gauge by replacing the sending unit.
I took the maiden voyage to my local gas station and filled her up. I think it took around 13 gallons or so (it was basically empty at this point) but can't remember the exact number, but the gauge went to full. I was excited to finally have a working gas gauge and not having to worry about diagnosing a 'no start' condition again only to realize I just ran out of gas.
I took it around the block a few times since I was out and brought it home. Since then I've really only had it running maybe 30-40 minutes idling in the garage working on it. Just took it out again around the block again to work out some kinks and noticed the gauge was already down to 3/4 full! I have a stock 360 magnum engine with an air gap intake, headers, and a holley 650 vac secondaries w/3.23 gears. I know I'm not going to be getting 30mpg (nor do I care all that much) but a 1/4 tank of gas that quick!? How?? Then I got to thinking...
The 72 demon is originally a /6 car with all the emissions crap, which was promptly removed when the 360 went in. Well when replacing the sending unit, I noticed that there was an additional steel line coming out of the gas tank at the top (presumably for the charcoal canister?).
Is it possible that all that gas is evaporating through that line? Can I plug it or is that needed regardless? I don't believe I have a vented gas cap but not positive...Any ideas guys?
I took the maiden voyage to my local gas station and filled her up. I think it took around 13 gallons or so (it was basically empty at this point) but can't remember the exact number, but the gauge went to full. I was excited to finally have a working gas gauge and not having to worry about diagnosing a 'no start' condition again only to realize I just ran out of gas.
I took it around the block a few times since I was out and brought it home. Since then I've really only had it running maybe 30-40 minutes idling in the garage working on it. Just took it out again around the block again to work out some kinks and noticed the gauge was already down to 3/4 full! I have a stock 360 magnum engine with an air gap intake, headers, and a holley 650 vac secondaries w/3.23 gears. I know I'm not going to be getting 30mpg (nor do I care all that much) but a 1/4 tank of gas that quick!? How?? Then I got to thinking...
The 72 demon is originally a /6 car with all the emissions crap, which was promptly removed when the 360 went in. Well when replacing the sending unit, I noticed that there was an additional steel line coming out of the gas tank at the top (presumably for the charcoal canister?).
Is it possible that all that gas is evaporating through that line? Can I plug it or is that needed regardless? I don't believe I have a vented gas cap but not positive...Any ideas guys?
