Vapor lock cured

[mlktst]

67 Charger has a 383 after 1st stop [ It is 97 degrees outside ] always hard to start ran rough a couple of miles, heat soaked or vapor lock you know ... Allen Bills at S and S carbs put a return line on my carburetor back to tank. Now it is 100 degrees outside I made 7 short stops car ran perfect each time i stopped NO heat soak NO vapor lock. I threw away the phenolic heat risers . Now I drive my car more, matter of fact thats all I drive hahaha. Hope this can help someone

 

[Cranky]

Good deal! Are your lines in the stock location? Never had a problem with mine and drove it everyday. You have 97 there now? Just now hitting 90 here but even though the humidity isn't all that high, the heat index is 99. Just came in from the shop and it doesn't feel that bad but it's real cloudy right now....

 

[coloradodave]

I thought Texas was HOT! Today we're gonna hit 108* in sunny Northern California....lol.

 

[mlktst]

Good deal! Are your lines in the stock location? Never had a problem with mine and drove it everyday. You have 97 there now? Just now hitting 90 here but even though the humidity isn't all that high, the heat index is 99. Just came in from the shop and it doesn't feel that bad but it's real cloudy right now....

Yes Cranky mechanical fuel pump stock lines I even wrapped them with heat sleeve, installed phenolic heat spacer between manifold and carb. I would still get heat soak It was a minor issue longer starting. idle bad a minute or so but drove me nuts can't stand that kind of inconvenient stuff. The actual test was done on last week when it was hot. I have a 26" champion radiator with factory shroud 18" mechanical fan on 1" spacer no clutch run 165 degrees on highway 190 long idle in traffic

 

[mlktst]

I thought Texas was HOT! Today we're gonna hit 108* in sunny Northern California....lol.

Hello Dave you guys are lucky it will cool off there at night. Here we match temperature with humidity to get it just right lol 100 degrees 100% humidity and the same at night. I like your caption about guns and parachutes I have used both many timesbut only for FUN .

 

[coloradodave]

You're right. It drops to about 80* after midnight. I had some experience with high humidity in the military. Didn't like taking a shower in the morning and never getting dry all day...Glad you got your problem sorted out. Stay cool...

 

[Bart K]

Not sure if this is related, but after I drive my car, when I park it in the garage, there is the strong smell of gas, but nothing is leaking. Anyone have any ideas?

 

[coloradodave]

This is normal for a carbureted car. The carb and the tank are vented to the atmosphere, so you're going to smell it in a garage. Once you're sure there's no actual fuel leaking, that's the end. Only cure is to add an aftermarket fuel injection system.

 

[Mike67]

Kinda summms it up..

 

[Bart K]

This is normal for a carbureted car. The carb and the tank are vented to the atmosphere, so you're going to smell it in a garage. Once you're sure there's no actual fuel leaking, that's the end. Only cure is to add an aftermarket fuel injection system.

Thanks for the info Dave! Much appreciated!

 

[khryslerkid]

Are you useing straight pump gas? Just curious...

 

[Bart K]

Are you useing straight pump gas? Just curious...

Yep, I am using medium grade Chevron gas for the 318.

 

[khryslerkid]

Yep, I am using medium grade Chevron gas for the 318.

I'm wondering what the OP is useing. It's all good!

 

[Lionized]

I've considered this conversion for my Bee. I believe there is a return line nipple on my sending unit and I already purchased the filter...just gotta get to it.

 

[coloradodave]

Thanks for the info Dave! Much appreciated!

You're sure welcome...

 

[440+6]

A couple of things I did where insulated the supply line from the pump to carbs, phenolic spacers, also insulated supply and return from tank to rocker, then wrapped my exhaust from about 6 inches in front of the tank to the tips.

 

[ckessel]

I've been seeing more fuel issues on friends and customers older cars around here. Issues with boiling over even when the ambient temperature is not that high. On my neighbors 68 c20, his boiling over hit from one re-fuel. He always gets it a the same station and never had a problem till he pulled into his house after re-fueling that one time. I believe there is more alcohol being put in fuel than we are led to believe and this is the main contributing factor to the lower boiling point. I will have to learn to use a hydrometer, my boss was tailing about this at work too, to further investigate my theory. In the mean time, you can also block off heat risers on the intakes and use heat shields under the carburetors. I don't think the phenolic ones work that well from what I've seen. The best ones I've seen and used were [unfortunatly] GM units from Vettes and Z28's. They are just one sheet of aluminum with a gasket on each side. The standard 4150 type flange unit can be had from Classic in the, cough cough, Camaro listing. The GM number was 3969835. The spread bore unit was 3969837 but am not sure if its re-produced. I've sold and used them on RV applications which are probably the worst for hot underhood air. For the b-motors on intake gaskets with blocked heat riser passages, get them from Mopar Performance. A-motors will probably be the same source or Fel Pro etc. I got the MP unit for my 440 and made a carb shield using the Classic unit as my template and made my own since I have material plus toollage to cut it out. Another note on the carb shields: stay away from the ones which are multiple layers of gaskets and aluminum, like more than 2 gaskets 1 aluminum, as they are vacuum leak city waiting to happen.

 

[Bart K]

In looking for a carb heat shield, all I can find are shields for 4 bbl carbs. Anyone know where to get one for the stock 2bbl Carter carb on the 318???

 

[HawkRod]

In my humble opinion, all heat shields, wraps, phenolic spacers, etc. will do is delay the inevitable. On a limited use race car (or street car), that might be fine. But if you want to drive the car and really have it be reliable I don't think they will work long term. Unless you can truly route the fuel in a place that it never heat soaks, I think the only real solution with today's pump gas is a fuel return to the tank. That goes hand in hand with fuel injection, and as good as those systems are getting, that would be my suggestion. I have a FAST FI system, but the FITECH systems now are very reasonable - about the cost of a high end carb. Since I have installed my system, I have NEVER had any vapor lock or fuel related issues, and that includes stop and go in 95+ degree weather with the A/C running. I drove my car across country and I am sold on FI systems. If you are going to really drive your car I really believe this is the best solution.

 

[Bart K]

In my humble opinion, all heat shields, wraps, phenolic spacers, etc. will do is delay the inevitable. On a limited use race car (or street car), that might be fine. But if you want to drive the car and really have it be reliable I don't think they will work long term. Unless you can truly route the fuel in a place that it never heat soaks, I think the only real solution with today's pump gas is a fuel return to the tank. That goes hand in hand with fuel injection, and as good as those systems are getting, that would be my suggestion. I have a FAST FI system, but the FITECH systems now are very reasonable - about the cost of a high end carb. Since I have installed my system, I have NEVER had any vapor lock or fuel related issues, and that includes stop and go in 95+ degree weather with the A/C running. I drove my car across country and I am sold on FI systems. If you are going to really drive your car I really believe this is the best solution.

Great post hsorman! Currently my only issue is a gas smell in the garage, granted I have not been driving the car a lot until I get some other safety issues addressed. However, I will keep the aftermarket FI solution in mind if I do see more fuel issues cropping up.