Fuel vapor odor-sealant? or live with it?

A/C leak testers also trigger on gasoline. Might try one to pinpoint the source. Smoke testing works on fuel systems too.
Years ago I made an adapter to fit a Ferrari fuel filler neck with an air fitting on it. I connect it with a leak down tester and pressurize the system with about 1 lb of air pressure. It makes leak finding easier but you need to be really careful. If you accidentally give it much pressure you'll be needing new fuel tanks.

 

One frequently overlooked item is the fat hose from the filler to the top of the driver's side tank. Mine looked fine when inspecting from the engine bay side, but when removed the hidden fender side was completely deteriorated. Very scary.

 

This will be the best $40 insurance policy you ever purchased:

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Agreed, these are super useful. You can check for leaks in your kitchen gas stove or BBQ grille or any other source of flammable fumes

Does your car have part 112641, the little motor fan that pulls fumes into the charcoal canister? Mine is missing and I definitely smell fuel fumes after shutoff. Without the fan and the air cleaner snorkel flap operating properly, you will have more fuel smell. I'm not sure if it affects the tank venting though

 

Match is cheaper

 

Lol, that's like using a lighter to shine light in your tank to check the level

"Hell, it seemed like a good idea at the time"

 

If the welds are cracked (its either that or a bad hose) I don't think you can.

 

Here's a tale:
I had a challenge with a fuel smell on my 308GT4, US car with charcoal cannister. Very-very tough to find! All new fuel hoses and new cannister. I noticed fuel weeping from carb plugs. Minor but enough to measure ~200HC from several spots. Carb rebuild and addressing plugs cured weeping but smell not fixed. Dove back in and discovered the brand-new Gates hoses with the low HC permeability specs written on the side had trouble sealing on one of the aluminum tank nipples. I saw intermittent 1,XXX HC readings (I'm still a Gates fan, but these new hoses are a higher durometer, and require more tightening to seal.) A-ha moment...but still the smell. I noticed I was getting HC hits by the filler neck, sometimes in the engine bay, sometimes by the fuel cap. So, I bought another filler neck hose to replace the 6-month-old filler neck hose. I was about to install the new filler-neck hose in the car when at the last moment, I decided to do a soapy water dunk test on the filler neck & cap even though I thought it highly unlikely that the filler neck or cap would be the problem. I discovered a filler-neck brazing defect directly under the large grommet that controls the filler neck-to-body movement. With ~1/2 psi of air, a significant stream of bubbles was seen. This explains why the HC hits were back and forth between the engine bay and the fill cap. As I wriggled the filler neck trying to get HC readings, I changed the leak path. I got a new filler neck and I'm soo glad to be rid of the smell. What did I learn? Be patient!

I would be surprised if this same problem shows up on another car, but who knows?

How we love them so!!!

 

Kind of why I mentioned pressurizing the system. Makes it easier to find small or intermittent leaks.

 

I used a smoker to put 1/2 psi in system but could not see the smoke. It used baby oil, made lots of smoke and made the garage smell like baby oil perfume & gasoline. I had it hooked up for about an hour and used a strong flashlight to look for smoke, but again, I couldn't see it. I re-read your post and 1 psi would help push the smoke through leaks. The smoker I have has a fixed regulator. Leaks can be tricky to find.

There's a camera which sees HC vapor made by FLIR. I thought this would be the cats-meow to actually see where the vapor is coming from. The oil refining industry uses these. The camera hovers at $100K, and the rental which is a bit tough to manage is iirc $500/day. The person I spoke with also cautioned that the settings are not perfectly intuitive or obvious. I see lots of downsides to getting involved with this. The camera might not see what you want, and IF something happened to it...........

 

Do you get pressure build up when you run your car? I found my ventilation flow check valve was installed backward on my QV. This essentially pressurized the fuel tanks every time it heated up. We would get small whiffs of gas when driving and after in the garage. Reversing the valve solved my issues.

Sent from my SM-P610 using FerrariChat.com mobile app

 

If you can smell it so will an OTC sniffer. Either AC or a gas sniffer as shown earlier. Use that with 1lb of pressure.

If it is carbed and the air box is not sealed the way the factory did it, it will never stop smelling like gas. There a 4 carbs full of gas evaporating.


Also a possibility it may not be gas. Jaguar back in the 80's had never ending complaints of gas smell in the trunk. A lot of money was spent looking for vapor leaks. 4 gas analyzers could not detect it and they are far more sensitive than anyones nose. It was finally found it was not gas at all. It was a non hydrocarbon glue used in the trunk upholstery.

 

This makes me feel a little better about the challenge of hunting down the fuel smells. I spent god-knows how long finding that filler neck problem.

Another lesson from experience is suspect e v e r y t h i n g !