stonecamp

My 65 six which I have owned since new has hada problem for years. In hot weather, 80+ degrees, in city stop and go traffic, it stalls and stumbles and vapor locks. It won't restart until it has sat for a while.It doesn't overheat according to the temp guage.
One obvious thing is that the fuel line from the fuel pump is routed from the fuel pump on the left side of the engine, lower mid engine around the the front of the head to the carb which is located on the right side of the engine.
The fuel line seems to be exposed to plenty of high temperature to cause fuel boiling and vapor lock.
Does this sound plausible and is there any fix? Would it help to insulate the fuel line?
The fuel pump is original. Could it be the culprit?

9teen65coupe

Vapor lock is very plausible and rerouting your fuel line is a possible solution. I had the same problem but i chose to use a phenolic spacer under the carb along with a heat shield carb gasket from holley and my problem was solved. The only difference is my 65 has a 289

mustangmatt63

Anything you can do to keep excessive heat away from the fuel line will help.You could also try a heat shield carb gasket but I am not really positive how that would help on a six since all mine have V8s.Good Luck with it!![8D]

Nosboss

I had the same problem for a couple of years with my '66 coupe. I found the problem to be in the fuel I was using. If the fuel is an ethanol blend it will vapor lock very easy. I am not sure where you are from or if that fuel is even available where your at. I used it cause it was cheaper than the other fuels and it took a long time for me to figure out what was happening. Hope this helps.

stonecamp

I have never used E85 but the more I think about it, I'm thinking that it started when they started reducing the lead in fuel.
It didn't do it when it was new.
I'm going to find a way to insulate the fuel line.

109jb

My first 70 fastback did the same thing and I would have sworn it was vapor lock, but it turned out to be a plugged fuel filter. The sintered bronze one screwed into the side of the carburetor. For some reason it would flow enough in all situations except when it was hot outside and just loafing along.

falconfixer

Yeah, but... The six has the exhaust and intake on the same side. I would suspect vapor lock as well. I second the phenolic spacer solution.

stonecamp

My '65 doesn't have a "screen" on the carb input. The fuel filter is on the fuel pump, a pleated paper filter in a screw-on can.

stonecamp

I can't find an insulating spacer. I guess there isn't enough demand for 6 cyl parts, ( 1 bbl carbs) I guess I'll have to make one and see if it works. There is an aluminum spacer on there but it is used to circulate coolant.

mySAVIOReigns

I think it's a combination of a couple things: most likely the service station you're filling up at uses E-10 (10% ethanol, 90% gasoline) - this would lead to it.

second, have you replaced the fuel system? I'm not saying it's needed, as the car seems to drive fine, but I wonder about the varnish in the system.

third, I would do like you said and insulate the fuel line against as much heat as you can.


I have a spacer if you want it.