Smell of gas, turns out not floats set too high

[Jim_Gruber]

I think I resolved the issue with raw gas smell when driving Bugsy. Thought it was an issue of gas going out overflow tubes and floats set too high but whenever it happened I could pop the bonnet and not detect any evidence of gas around the overflow tubes. Grosse Jets are installed on my SU's and I thought I might need to change out to Vitron Tipped Needle Valves as a cause. Had the car running at various speeds in driveway with bonnet up for 20 minutes with no evidence of gas overflow occurring. A head scratcher for sure.

Think Gruber think where else could I get a gas smell to come from... H'mmm I replaced the intake manifold gasket last year and both carbs and manifold were off of the car. 7/16" wrench in hand discovered that both Carbs and Intake manifold could take at least 1/4 to 1/2 turn on all nuts. At this point seems to have solved the issue after one test drive. Guessing that normal driving caused these nut to loosen up as they were tight when I reinstalled carbs and manifold last year.

Now will be curious to see if one more flat leaner will turn plugs the correct color now. They have gone from black and sooty to dark grey at this point in time.

 

[spritenut]

Jim

I am having this same problem on my 59.
I just rebuilt the carbs, nothing is loose and nothing shows up leaking.
After a few times smelling gas, I realized it was only after a turn or sharp curve at speed. The rubber mounting things where the float bolts to the carb body were very soft rubber in the kits I had. I could wiggle the float bowls easily by hand but the bolt was tight.
I replaced those mushy rubber things with some old hard rubber ones and the smell is gone.
I am thinking the floats pivoted on a turn and dumped fuel into the carb where it spilled out into the air filter. Nothing ever came out of the bowl lid or overflow but I did test this theory by moving the bowl and watching the gas spill into the carb body via the jet tube. Mine was only the front carb but both had the mushy rubbers on them.
If that's not it, then it's gremlins for sure :wink:

 

[Jim_Gruber]

Thanks Frank,

Gotta do some more test driving to see if issue is gone but next step is the replace the Grosse Jet with new Vitron seats from Joe Curto. It's either that or go back to old style carb tops/floats from a spare set of SU's I have in the back of the garage. Time to do some more driving this weekend. I hate having to put in so much time "Test Driving". Honey see you in an hour or two...

 

[jlaird]

You poor sole Jim.

 

[Jim_Gruber]

I know Jack, you feel for me. Thanks for the moral support for this arduous task ahead tomorrow. Drive!!!!!