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Discussion Starter · #1 ·
my 57 is outgassing somewhere. I have checked the entire system for a gas leak but can't find anything. Does anybody have any advice where these gas odors might be coming from?
thanks, mike
 

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Hi Mike , I have the same problem with my cars . The 32 roadster is the worst . It has a holly carb and a tank vented to atmosphere . My 56 is not as bad it has 2 ABF's and a stock tank vent. It's mostly caused by evaporation .This is why auto builders went to the carbon canister system . Don
 

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Mike,
Did you just fill up? I had an issue with my sender and I only discovered that, when I filled the tank.
 

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Just a guess here but do you have your exhaust system close to your tank?
If so,the exhaust will heat the tank and make it vent more fumes.
Another thought would be,what carb. are you running? I had a 1906 carb(like the qaudrajet) and it would leak fuel into the intake runners and would give off strong fumes.Qaudrajets would do the same.
One dead give away would be that you would have to 'pump' the carb to get the engine to fire after sitting for a few days.Good luck-Keith
 

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Mine would stink up the garage too. I couldn't find a hint of a leak and it would only do it after running up to operating temperature. I have a Weiand intake on mine that has the exhaust passage under the carburetor and the carb would get extremely hot. You couldn't touch the intake in that area or carb after driving it. Aluminum transfers heat very well and I am sure it was vaporizing some of the gas in the carb. I pulled the intake, and blocked the passage with a piece of stainless shim stock that was about .016" thick. I bought an intake gasket that was solid over the exhaust port and milled out a place about half way thru the thickness of the gasket for the stainless shim block using a rotozip. You can buy gaskets that have the sheet metal block plates with them, I just didn't like the one I looked at at the local Advance. I put it back on along with a 3/8" thick insulating carb gasket and mine is 95% better.
 

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my wife complained of the gassy smell right ater i bought the 57. the q-jet was seeping out of the epoxy plug on the bottom - put on a "new" one and the smell is gone.
 

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Braided lines in play, here??
 

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I suddenly developed an awful gas smell with my stock 6 cyl 56. I looked everywhere and couldn't locate the leak. Finally I crawled up under the fuel tank and after running my hand all around I found a wet spot on the right side top of the frame just below the gas tank. After pulling down the tank I found a very tiny hole that was weeping gas. Be careful of gas fumes in your garage. You don't want to create explosive levels of gas fumes that could possible ignite:eek: I've seen that a few times in my Firefighting career.

Don
 

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Had a strong gas smell in my garage at one time. Followed my nose right to my lawn mower with a rotted rubber gas line :eek:

Good luck :tu
 

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I have been dealing with the same problem, just replaced gas tank with a new one for the second time in the last month. The first time the problem was I had the new tank powder coated and it leaked around the seam where
the fiiler tube fits ioto tank. After removing AND GETTING ANOTHER new tank It is now leaking where the sending unit fastens. The next step is to remove sending unit ,put new gasket on and put some sealer on with the new gasket. Hope this fixes leak.

Jim, 56 BELAIR 2dr sedan
 

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Jim do a search here about this gasket. some say you have to replace the gasket that comes with the tank for a cork (?) gasket and be sure to use the washers under the screw heads.

Don
 

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Discussion Starter · #14 ·
Interesting comments - yes I do have ss braided gas lines from the fuel pump in the truck up to the front - but I checked that and could not detect any leaks - so I concluded it is something else.

When I first got the vehicle a few months ago, I didn't notice any gas odors - but I did fill the gas tank pretty full (the gage wasn't working, so I couldn't tell how much fuel was in it), anyway - it seems the odors got much worse after that. But I checked the sending unit - seems to be ok, no leaks that I can see??

I can't get a good look where the filler neck joins the tank.

I also heard the 57 was vented with a small slit on the filler tube - this seems impossible? has anyone heard of this?

Thanks again for all your suggestions,
Mike
 

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"Interesting comments - yes I do have ss braided gas lines from the fuel pump in the truck up to the front - but I checked that and could not detect any leaks - so I concluded it is something else."
U may not see a leak... Some of the braided hose will "wick" fuel thru it's liner, and not show on the braid....BTDT, and threw a complete cheapo Earls line set in the trash....
 

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I also heard the 57 was vented with a small slit on the filler tube - this seems impossible? has anyone heard of this?
No. The 57 filler tube is vented, but with smaller diameter tubes coming off the main tube and has a rubber tube connecting them. Then the gas cap should be vented too.
Terry
 

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Discussion Starter · #17 ·
well thanks for the help-turns out I found my braided gas lines seeping. Was really smelling up the place. Not sure I got em all, I have several more ss braided lines to check.
Thanks again, Mike:):)
 

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well thanks for the help-turns out I found my braided gas lines seeping. Was really smelling up the place. Not sure I got em all, I have several more ss braided lines to check.
Thanks again, Mike:):)
SS braided lines are kinda like my wife - pretty, tough enough for even the roughest environment and VERY high maint. Except the part where ya gotta replace at least every three to five years! :eek:
 
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