Author Topic: Gas smell  (Read 1146 times)

Offline Jbh0007

Gas smell
« on: April 04, 2017, 07:54:17 PM »
I thought I had read about this issue somewhere before.  I did a search but couldn't find anything.  Anyway, when I fill my car with gas (I never fill over three quarters of a tank) the gas smell in my garage becomes really strong for several days.  Anyone have this issue or advice on how to resolve it?  At half a tank or less there is no odor at all.

Offline 62 driver

Re: Gas smell
« Reply #1 on: April 04, 2017, 08:11:30 PM »
Is gas dripping down?

Offline Clewisiii

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Re: Gas smell
« Reply #2 on: April 04, 2017, 08:18:29 PM »
Vent tube?
Crack in rubber boot vent tube to tank?
Hole in top of tank?  I had one  Strange the bottom never got a hole
Crack in rubber boot from fill neck to the tank?


Some people say close off the vent tube and use a vented cap.
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Offline russ austin

Re: Gas smell
« Reply #3 on: April 04, 2017, 08:54:03 PM »
More than likely it is a bad rubber connection for the vent tube. The hose cracks after all these years. I think it is 5/8 hose. It's an easy fix, so get under the car.
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Offline Dan LeBlanc

Re: Gas smell
« Reply #4 on: April 05, 2017, 06:41:32 AM »
Use of a vented cap and blocking off the tank vent would create issues filling the car.  Cars that use a vented cap (such as my former 63 Impala) had a special neck with a vent built in.  Just blocking off the tank vent and installing a vented cap would give the air nowhere to escape when filling the tank and you'd have burping and a very slow fill process.
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Offline Willits

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Re: Gas smell
« Reply #5 on: April 05, 2017, 07:03:51 AM »
The vent hose was missing on mine when I got and the garage did smell of gas often.    With a full tank and braking too hard gas would spill out of the vent and leave a puddle.    I bought a length of fuel hose tied it into an upside down U and have had no issues since installed.   
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Offline Jbh0007

Re: Gas smell
« Reply #6 on: April 05, 2017, 03:09:34 PM »
Thanks! There are no leaks that I can find.  The tank is pretty new as is the fill tube.  The vent tube goes up to an inverted U and hangs on the drivers side frame rail above the tire.  It is pretty old so that sounds like where the trouble may be.  The vent tube has no vapor recapture at the end and from what I can tell in the manual, it isn't supposed to.  I assume the upside down U is supposed to trap the vapor.

Offline Jeffrey A. Rogers

Re: Gas smell
« Reply #7 on: April 05, 2017, 04:59:52 PM »
you could easily remove the vent tube and visibly check for cracks, age, leaks.  An easy fix if it's the problem.

Please be careful.   
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Offline Jbh0007

Re: Gas smell
« Reply #8 on: April 05, 2017, 09:35:36 PM »
Thank you.  I may have figured it out.  Even though I could not find any obvious leaks, it appears as gas may be coming from the top of the tank and running down to the welded lip and evaporating before going any further or dripping and evaporating from the floor.  This leads me to believe that there could be a leak at the sending unit gasket.  I hate taking the whole tank out but that's what it is looking like.

Offline Externet

Re: Gas smell
« Reply #9 on: April 06, 2017, 07:28:41 PM »
It you install a valve at the end of the inverted U breather tube, it will help to eliminate the fuel smell.

I used a brakes booster vacuum valve, in such way that allows air to get into the tank as fuel is consumed, but is closed to venting fumes out.  It may cause slower refueling at high tank levels.
A not recommended vented cap may spill fuel out on acceleration.
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