Gasoline Smell - 1966 L79

[Rich G.]

Re: Gasoline Smell - 1966 L79

My 66 L79 did that twice. Once was the sender, next was the fuel pump. With those fixed no more smell ever. If you just noticed this, it's probably a leak.

Rich

[Jeffrey B.]

Re: Gasoline Smell - 1966 L79

When I come in from a drive in my 66, after I pull into the garage, I loosen the wing nut and take the top off of the air cleaner to allow it to vent heat and fumes from the carburetor with the hood open until it cools off. Of course I let the garage door open so the fumes dissipate. The fumes don't bother me but with my wife it's a different story, I often wonder if these cars gave off the gas odor when they were new back in the day.

[Leif A.]

Re: Gasoline Smell - 1966 L79

Absolutely, they did. That smell, today, is what triggers so many wonderful memories of my youth. Kind of like the vinyl smell of the '60s GM cars...very distinct and a definite memory trigger.

[Tony S.]

Re: Gasoline Smell - 1966 L79

Check your fuel sender, especially if you have one of the modern Chinese examples. They can leak and stink up a garage.

[Frank D.]

Re: Gasoline Smell - 1966 L79

A properly maintained car did not reek of gasoline when parked "back in the day"...my Dad was a used car salesman for all models over the years; we (as most did) had a small one-car attached garage, poorly insulated from the 1,000 sq ft house. Not the behemoth man caves of today.

If the smell of raw gas was normal the entire house and its contents would have stunk accordingly. They didn't.

[Stuart F.]

Re: Gasoline Smell - 1966 L79

I agree. We too had a single attached garage with a small 3 bdr. home in Hinsdale, IL where I kept m 63 for many years and I don't recall any gas smell problem unless it was when I changed a fuel pump, and that disappeared fast. Must be the gas as today in a 2 car attached I've been fighting the gas smell for years. I now run non-ethanol and I seldom notice any smell, plus I eliminated the hot soak percolation problem some years ago.

Stu Fox

[Leif A.]

Re: Gasoline Smell - 1966 L79

Frank and Stu,
I believe the OP was asking about the gas fumes smell immediately after a drive and did that smell exist "back in the day". My answer to that was an unequivocal "yes", because they did. That smell would dissipate after several hours. But, as I mentioned earlier, if the strong smell of gasoline persists then there is more than likely a leak (of some kind...fuel, vapors, etc) from somewhere.

[Frank D.]

Re: Gasoline Smell - 1966 L79

Frank and Stu,
I believe the OP was asking about the gas fumes smell immediately after a drive and did that smell exist "back in the day". My answer to that was an unequivocal "yes", because they did. That smell would dissipate after several hours. But, as I mentioned earlier, if the strong smell of gasoline persists then there is more than likely a leak (of some kind...fuel, vapors, etc) from somewhere.

Not worth debating - the owner in the thread clearly has something amiss...

[Joe L.]

Re: Gasoline Smell - 1966 L79

A properly maintained car did not reek of gasoline when parked "back in the day"...my Dad was a used car salesman for all models over the years; we (as most did) had a small one-car attached garage, poorly insulated from the 1,000 sq ft house. Not the behemoth man caves of today.

If the smell of raw gas was normal the entire house and its contents would have stunk accordingly. They didn't.

Frank------


It does not take very much gasoline in a confined space to create an aroma of gasoline. If evaporative loss of fuel did not occur, whether in a confined space or not, then there would have been no need for evaporative emissions controls.

[William F.]

Re: Gasoline Smell - 1966 L79

Some smell is normal. The smell of the emissions from exhaust of an L79 in addition to some gas smell due to vented carb fuel bowls and vented gas cap. But do rule out leaks as suggested. Also check carb float levels and after shutdown, look down into carb and make sure no gas is dribbling out of venture boosters.

[William F.]

Re: Gasoline Smell - 1966 L79

Also do check for a ruptured power valve . Test described in archieves.

[Joe C.]

Re: Gasoline Smell - 1966 L79

Absolutely, they did. That smell, today, is what triggers so many wonderful memories of my youth. Kind of like the vinyl smell of the '60s GM cars...very distinct and a definite memory trigger.

Ah yes........reminds me of the smell of napalm in the morning...............

My internet dropped out three days ago, and I just now got it restored. I notice that my post of three days ago in this thread never went through. I asked, kinda hypothetically but then again no...................how old the OP is? I also asked if he knew the difference between the dee-lightful smell of exhaust and that of raw gas.

Raw gas smell is semi-normal now but was not normal "back in the day" . If your carb is not perking due to heat soak then you should not smell raw gas unless there's a leak somewhere else. Many, if not most Corvetters don't have heat soak problems. BTW: The reason for heat soak perk is because of the ethanol in the gasoline. Now, exhaust smell is an entirely different matter, as my bud Joe (looooaAAbstah) Lucia kinda alluded to earlier. Most vintage engines will leave a distinct exhaust smell in your garage (less the acrid twinge of lead, which is GONE) which should dissipate after awhile. The bigger the cam in your vintage engine, the more exhaust smell you will have in your garage and the longer it will take to go away.

[Joe C.]

Re: Gasoline Smell - 1966 L79

Also do check for a ruptured power valve . Test described in archieves.

William,

Most times the engine won't idle with a ruptured PV, and if it does it will be rough as h#ll.

[Frank D.]

Re: Gasoline Smell - 1966 L79

Ah yes........reminds me of the smell of napalm in the morning...............

My internet dropped out three days ago, and I just now got it restored. I notice that my post of three days ago in this thread never went through. I asked, kinda hypothetically but then again no...................how old the OP is? I also asked if he knew the difference between the dee-lightful smell of exhaust and that of raw gas.

Raw gas smell is semi-normal now but was not normal "back in the day" . If your carb is not perking due to heat soak then you should not smell raw gas unless there's a leak somewhere else. Many, if not most Corvetters don't have heat soak problems. BTW: The reason for heat soak perk is because of the ethanol in the gasoline. Now, exhaust smell is an entirely different matter, as my bud Joe (looooaAAbstah) Lucia kinda alluded to earlier. Most vintage engines will leave a distinct exhaust smell in your garage (less the acrid twinge of lead, which is GONE) which should dissipate after awhile. The bigger the cam in your vintage engine, the more exhaust smell you will have in your garage and the longer it will take to go away.

I drove every kind of car imaginable home from Dad's used car lot 'back in the day'.....from Renaults to bathtub Porsches to Shelbys to Corvairs. If I smelled raw gas I was under the hood...it meant danger. Now if you had an early Corvair the gas smell from the zany spark plug heater could knock you out...that's an exception. I have a 3 car garage now and with three classic cars in it at one point (all 95% original) still no gas smell.

Not when I first shut them down, or first start them up, or, after sitting...WCFBs, AFBs and a Holley. If they did the wife would be all over my backside.

Go figure.

[Joe R.]

Re: Gasoline Smell - 1966 L79

Ned, Try shutting the car off outside the garage and letting it cool off. Then bring it into the garage after it has cooled. You may just be smelling the fuel evaporating out of the carb bowls. Because of the low boiling point of current gas along with the high heat of the engine after its been driven then shut off you will get some residual fuel smell.

I have personally experienced what Joe Scafidi describes above, and I know other '67 owners that have experienced it. Today's fuels seem to have a lower boiling point than the fuels of the 1960s. If the car is parked with the engine hot, sometimes the heat soak causes the fuel in the fuel bowls to boil. Even if the fuel doesn't quite boil, the hot gas still throws of a lot of fumes.

While I think all Holley carbs have bowl vents that are open to the atmosphere (those two tubes that stick up into the air cleaner), the 1967 small block carb has an additional vent on the top surface of the front bowl. This vent is in the form of a rubber disk that sits over a hole in the top of the bowl. The carb linkage is arranged to open this vent whenever the throttle is in the idle position, such as when the car is parked.

I have no idea why Holley decided to add this feature in 1967, but they didn't use it for very long. Most Holley carbs do not not have this added vent. However, the combination of volatile gas and this open vent on the front bowl is a good recipe for gas odors, even if there are no actual leaks anywhere in the system.

I see that the OP lives in Texas where temperatures can get pretty hot. To reduce the heating of the gas in the carb, it helps to replace the heat riser valve with an open spacer, block the exhaust crossover path under the carb, and install a phenolic insulating spacer under the carb. This will probably keep fuel from boiling in the carb, but there will still be some emission of gas fumes after the car is parked hot.