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Here is a suggestion to help overcome vapor lock. On air conditioned cars one of the AC lines is cold when the system is operating. Could one re-route the fuel pump to carburetor line so it could be clamped to the cold AC line for cold transfer? Just a suggestion. Look forward to hearing your views on this.

(o{I}o)

The a/c line on my car is on the opposite side of the car. Re-routing the fuel line would be quite an undertaking, but it sounds like a plan. The way I solved vapor locking is by hooking up an electric fuel pump.

Interesting idea. I know that's the pipe that gets all the shielding and added doodads to cure vapor lock. From what I've read, not always successfully though.

It does run close to heat which undoubtedly contributes but have found it interesting that an electric pump at the back of car usually seems to resolve the issue for almost all. The pipe in question is most of the time under some pressure from the mechanical pump so would think it would not be the culprit as much as the feed line before the pump which operates under reduced pressure.

Since the usual electric pump installation pressurizes that supply line to essentially same level as the pump to carb pipe and usually ends complaints, would think the answer is more complicated than just one section.

West and HH56, good comments. I got the idea from a Jag Tech Session on Saturday. I went with a friend as a guest. There I saw a vintage V-12 fuel injected Jag that had the return fuel line bracketed to the cold AC line with a heat (cold) sink. Jaguar did this to cool the fuel being returned to the tank. It may be something to consider for those who do not want an electric fuel pump.

(o{I}o)

Thats a good idea. Wonder why more mfgs didn't think of doing something similar or is it not an issue with them. As I recall, Jags had a bit of overheating problem and V12s maybe even more -- so that might be the reason they came up with it but think others might benefit.

Wonder how a Peltier module or heat pipe setup would work for those without AC. Peltier might draw too many amps for a decent size but easy & cheap enough to do. A passive adsorptive refrigeration cycle might work too-- maybe take advantage of exhaust pipe heat. That would require some engineering though.

two or three wooden clothes pins clamped on the fuel line will do the trick. You can always take them off when you get where you are going. I know it sounds strange but it works, that's the key.

Having the fuel pump in proper condition, no warpage in the housings where they mate, a good, current-material diaphragm and having the factory heat shields in place, along with properly routed lines will go a long way towards eliminating fuel system problems. The flex line from the frame to the pump should be inspected and replaced if cracked, and the hard line going back to the tank should be inspected for rust or holes and the tank should be cleaned and possibly coated if need be.