I have a metal line that connects to the fuel pump with a B-Nut. It runs almost all the way to the carb. It does lay on some eng areas that get really hot. Is there a way I could insulate it just to make sure? The line has got to be at least 3/8. James
You need to get the fuel line away from the other surface, it should not touch. If you notice in the picture above I have rubber fuel line and have had that arrangement for years with out a problem. As far as vapor locks go, you need to keep the line away from hot surfaces. Mine has a metal line from the pump to just about the top of the power steering pump bracket and from there it is rubber. In neither case is the line closer than 2 in. of the engine.
If that doesn't fix the problem some other possibilities already mentioned need to be checked.
1. Fuel pump
2. Fuel line clogged
3. Worn concentric that drives the fuel pump
A pressure gauge should tell you if you have a problem in one of these. Also as mentioned by roach57 a clear filter will let you see what is happening with the flow.
Also there are two rubber connections in the stock metal line. One from the tank to the metal line and one about 1/2 way up the chassis between two sections of metal line. Check the condition of these for cracks or holes, I had a mouse nibble thru one once causing a flow problem by sucking air, no leak just air sucked in by the flow of fuel.