Hotter outdoors temps cause her to buck and cut out.

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idahovette

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Not much fuel in that filter!
 

dustyduds

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Had just replaced the fuel filter when I took that pic.

Has anyone tried any of the heat shield tapes or sleeves like Cool Tape or Fire Sleeve? If you have, please let me know how that worked. Also, where did you place the tape or sleeve? I think Design Engineering makes most of that stuff.
 

CoggedBelt75

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I used the tubular pipe insulation from Lowe’s, or any hardware store sells it. Cheap and holds up well to the heat. Used from the tank to fuel pump and the outlet line to filter that runs real close to lower hose.

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Fortarel

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I'm a newbie also. I had a similar issue, but not bucking, more of a classic vapor lock in my 81 3+3 454 stock, which had never vapor locked in all the years I owned it. I'm not a mechanic so suffered a lot of different trial and errors in resolving the issue. Found a mechanic who is a big GM/Squarebody guy and he put in an electric fuel pump. Problem solved. He said he had been encountering this same problem on other folks trucks, so when I showed up it was an easy diagnosis. About the only theory he could arrive at (no vapor lock for years, then vapor lock) was quality of fuel. Truck runs fine now in high temp with AC. Once in a while you can tell it want's to die, but I guess the pump just forces the fuel.....
 

fussfeld

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If it runs alright in cooler weather but not so well in the summer heat, Somethings going on with the fuel heating up like everyone’s saying. Could be because of no return line, but I don’t have one and no issues in our triple digit temps. Looking at the last pic, it appears by the rub mark on the fuel line that it is making constant contact with the lower radiator hose. More than likely boiling the fuel in the line. You might try isolating the two. Or better yet, reroute the line away from the heat source altogether. Even the line feeding the pump “looks” close to the lower hose as well.


Are you injected?
 

dustyduds

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I'm not injected; Edelbrock 1406. I've put pipe insulation on the fuel lines going into and out of the fuel pump. Also had a friend clean up the carb because it was so dirty and the right side idle screw was not making any adjustment, stuck float. I'm finally ready to reinstall the carb.

Any ideas as to what the blue wire is that runs behind the distributor? It comes through the firewall and just stops behind the distributor. Someone had wrapped it with electrical tape and left it in the loom with the other wires. I can't find any wires that it could connect to.

Thanks so much for all the suggestions on my vapor lock problem. I'll post more when I know more.
 

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