Gas Smell
Thread Starter
Heel & Toe
Joined: Feb 2019
Posts: 21
Likes: 5
From: Nashville Tennessee
Gas Smell
My 1975 has all the sudden gotten a super strong gas smell when I shut it off. Have checked carburetor (Holley 600) and nothing seems out of the ordinary. The only thing I see that is questionable is that the fuel filter (plastic WIX see through) has barely any gas in it, around 1/4 of the way full), when its running. Any ideas?
Thanks
Thanks
Le Mans Master
Joined: Nov 2001
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From: LONG ISLAND
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My 1975 has all the sudden gotten a super strong gas smell when I shut it off. Have checked carburetor (Holley 600) and nothing seems out of the ordinary. The only thing I see that is questionable is that the fuel filter (plastic WIX see through) has barely any gas in it, around 1/4 of the way full), when its running. Any ideas?
Thanks
Thanks
Thread Starter
Heel & Toe
Joined: Feb 2019
Posts: 21
Likes: 5
From: Nashville Tennessee
1967 Pedal Car Champion
Joined: Mar 2020
Posts: 9,068
Likes: 4,200
From: US-PNW
Unless you have an obvious fuel leak at the fuel tank, pump or carb, strong fuel odor is usually something to do with the EVAP vapor system. n2h2o2's suggestion to look at the charcoal canister (engine compartment behind the driver-side wheel well) is just part of the EVAP system, so more needs to be inspected.
- With a flashlight, inspect under the gas tank on the driver's side. You're looking for signs of fuel seeping down the side of the spare tire carrier and/or on top of the muffler. If you see signs of this, it's likely the fuel separator "valve" mounted to the upper corner of the tank. These are prone to splitting of the housing or internal failure of the baffle. It separates liquid fuel from tank vapors.
- The tank vapors are pulled to the engine along the frame rail to the charcoal canister. The PCV system pulls the vapors to the carb where they are burned off. If the separator isn't working correctly, the canister can get contaminated with liquid fuel which saturates the charcoal. Check the hoses at the canister to ensure they are snug on the nipples - maybe cut 1/2" from each to get a non-stretched segment and reinstall.
- If the above doesn't yield any strong suspects, inspect your gas cap (it should be marked non-vented) and its gasket seal under the lip.
1967 Pedal Car Champion
Joined: Mar 2020
Posts: 9,068
Likes: 4,200
From: US-PNW
Did you remove the separator on the tank or at least cap off the nipples?
Thread Starter
Heel & Toe
Joined: Feb 2019
Posts: 21
Likes: 5
From: Nashville Tennessee
I did not, when I dropped the tank in July-ish of last year to replace the sending unit I just hooked the old hose back up. I did run new supply and return rubber lines though. The only fuel lines that haven't been replaced besides the evap lines are the rubber lines from the frame to the pump.
Last edited by SR75; Oct 14, 2023 at 12:53 AM.
Team Owner
Joined: Mar 2002
Posts: 44,650
Likes: 1,827
From: Huntsville AL
Unless you have fuel pooling in the intake after shutdown or an obvious leak the culprit is most likely the E.E.C. Valve (Separator Assembly) that is mounted at the top of the fuel tank on the left-hand side. The ball inside gets stuck allowing fuel to get into the vapor canister and that is what you're smelling.
I haven't read anything good about the repop E.E.C valve the vendors sell.
.
I haven't read anything good about the repop E.E.C valve the vendors sell.
.
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Le Mans Master
Joined: Aug 2017
Posts: 8,336
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From: Cool Northern Michigan
On some Holleys a metering block gasket, a fuel bowl gasket and sometimes the accelerator pump gasket can weep. Not dribble. Weep.
You can get a strong gas smell at shut-down but no visual of drips. The only clue is, again sometimes, a gas stain under the carb.
Not my car but, why do you feel the need to know if gas is flowing through the lines?
Those plastic or glass in-line filters are mauldov cocktails waiting to go off.
Those gas bombs should only be sold as a kit: One Filter, Two Hose Clamps and One Fire Extinguisher.
You can get a strong gas smell at shut-down but no visual of drips. The only clue is, again sometimes, a gas stain under the carb.
Not my car but, why do you feel the need to know if gas is flowing through the lines?
Those plastic or glass in-line filters are mauldov cocktails waiting to go off.
Those gas bombs should only be sold as a kit: One Filter, Two Hose Clamps and One Fire Extinguisher.
Burning Brakes
Joined: Dec 2021
Posts: 805
Likes: 260
My 1975 has all the sudden gotten a super strong gas smell when I shut it off. Have checked carburetor (Holley 600) and nothing seems out of the ordinary. The only thing I see that is questionable is that the fuel filter (plastic WIX see through) has barely any gas in it, around 1/4 of the way full), when its running. Any ideas?
Thanks
Thanks
Burning Brakes
Joined: Dec 2021
Posts: 805
Likes: 260
On some Holleys a metering block gasket, a fuel bowl gasket and sometimes the accelerator pump gasket can weep. Not dribble. Weep.
You can get a strong gas smell at shut-down but no visual of drips. The only clue is, again sometimes, a gas stain under the carb.
Not my car but, why do you feel the need to know if gas is flowing through the lines?
Those plastic or glass in-line filters are mauldov cocktails waiting to go off.
Those gas bombs should only be sold as a kit: One Filter, Two Hose Clamps and One Fire Extinguisher.
You can get a strong gas smell at shut-down but no visual of drips. The only clue is, again sometimes, a gas stain under the carb.
Not my car but, why do you feel the need to know if gas is flowing through the lines?
Those plastic or glass in-line filters are mauldov cocktails waiting to go off.
Those gas bombs should only be sold as a kit: One Filter, Two Hose Clamps and One Fire Extinguisher.
Thread Starter
Heel & Toe
Joined: Feb 2019
Posts: 21
Likes: 5
From: Nashville Tennessee
On some Holleys a metering block gasket, a fuel bowl gasket and sometimes the accelerator pump gasket can weep. Not dribble. Weep.
You can get a strong gas smell at shut-down but no visual of drips. The only clue is, again sometimes, a gas stain under the carb.
Not my car but, why do you feel the need to know if gas is flowing through the lines?
Those plastic or glass in-line filters are mauldov cocktails waiting to go off.
Those gas bombs should only be sold as a kit: One Filter, Two Hose Clamps and One Fire Extinguisher.
You can get a strong gas smell at shut-down but no visual of drips. The only clue is, again sometimes, a gas stain under the carb.
Not my car but, why do you feel the need to know if gas is flowing through the lines?
Those plastic or glass in-line filters are mauldov cocktails waiting to go off.
Those gas bombs should only be sold as a kit: One Filter, Two Hose Clamps and One Fire Extinguisher.
1967 Pedal Car Champion
Joined: Mar 2020
Posts: 9,068
Likes: 4,200
From: US-PNW
I did not, when I dropped the tank in July-ish of last year to replace the sending unit I just hooked the old hose back up. I did run new supply and return rubber lines though. The only fuel lines that haven't been replaced besides the evap lines are the rubber lines from the frame to the pump.
Did you, by chance, have a spirited drive with a fairly full tank before you noticed the fuel smell? If so, the separator valve is likely the culprit.
Thread Starter
Heel & Toe
Joined: Feb 2019
Posts: 21
Likes: 5
From: Nashville Tennessee
If I'm understanding, you reconnected the vapor lines (driver's side) at the tank/valve to the frame rail's hard line that runs to the canister but no longer have the canister and capped the line there? You could still have valve failure at the tank so that fuel is leaking there.
Did you, by chance, have a spirited drive with a fairly full tank before you noticed the fuel smell? If so, the separator valve is likely the culprit.
Did you, by chance, have a spirited drive with a fairly full tank before you noticed the fuel smell? If so, the separator valve is likely the culprit.
1967 Pedal Car Champion
Joined: Mar 2020
Posts: 9,068
Likes: 4,200
From: US-PNW
I just noticed that '75 doesn't use the separator valve - that stopped in '74 - I assumed it had one. I'll bow out and let someone more knowledgeable with the '75 setup address how the vapor line may allow fuel to the canister.
Team Owner
Joined: Mar 2002
Posts: 44,650
Likes: 1,827
From: Huntsville AL
