So I recently bought a 64 f100 with 390 has a 650 edelbrock carb msd box and a Holley intake basic performance parts. Truck sat for about 3 years till I convinced my dad's friend to sell it to me ran awesome when I brought it home it has a toploader and 456 gears so it gets up and moves pretty decent so for the fact it sat so long I decided to run some sea foam through it started running rough filled it with new fuel ran good I decided to order some moroso plug wires and new plugs while I was waiting for those to arrive I realized ever since I used sea foam it diesels when shutting off so I drained fuel put new fuel in ran good than same thing so i decided to wait and do the tune up I started to clean up wiring for the fact it was a mess and all the msd connections and coil connections where just twisted together and taped I got my new plug wires and plugs gapped them at 35 they are autolites put a new cap on and an accel coil I had laying around after tune up it ran like it had lost tons of power I tried using old coil no change I changed gap to 45 it doesn't rev good yes accelerator pump is working I've tore carb aprt and cleaned when it gets to around 190 200 degrees you shut it off let it sit and try and start it and you have to hold pedal to the floor to get it to fire it runs rough you rev motor and tries to die haven't touched timing for the fact it ran so damn good when I first got it any info helps and I have changed fuel filter seems to get plenty of fuel
You should use some periods and commas, because it's hard to figure out where the second quote below, starts or ends: This by itself, sounds like gas leaking into carb throat, when motor is shut off. It could be leaky needle valve, caused by a flake of dirt. Or, if hot enough under the carb, and higher content of methanol/gasahol. then the gas could be boiling and forced down the carb. Next time you shut it down hot, look down the carb. Can't tell where the commas should be. If you mean it cuts out when you hit the pedal, then it sounds like it's a lean condition, like the accel not spraying enough....that's if the timing is OK, and if it's advancing enough. BUT, if it runs so raggy like way too rich, the extra gas from the accel, could make it worse as you hit the pedal... Does it ever idle decent at a normal low idle speed? .If it never has a good idle, it could be more things, like vacuum leaks.
It idles fine when its a cold motor. If you let it warm up go drive around the block come back shut it off it is hard to start and won't idle good. sometimes motor will just die. And you have to try and peddle it to keep it going
so, why did you run seafoam in the first place? sounds like it might have loosened up carbon deposits inside heads. what octane gas (ethanol) did you put in it? what was condition of carb when you took it apart - very clean or? was there a spacer between carb & manifold? plugs the same as ones you took out? is there more than one fuel filter - replaced? distributor advance working properly?
Plug gap should be .034 and point gap should be .017 on that one. Point style ignition doesn't usually like as much gap as you put in the plugs if you are running .045. I'm with Jalopy Joker in that your main problem is that between the Seafoam and the new gas they have loosened up crud in the tank and lines that is now in the carb plugging circuits or holding the needle open. I've seen similar things happen on too many rigs that sat for extended periods of time and then someone got them running and they started acting up when dirt or crud plugged up the filter or carb. Including the OT rig I got running this morning after a carb rebuild. That one also had a bad float but it is a quadrajet carb so that is almost a given.
It has an MSD ignition, and the MSD wire 'harness' was attached by the P.O. by winding wires together... The O.P. first repaired the sloppy wire connections, and changed coils; ran badly when warmed up, so the original coil was put back on. Presently displays said problem. In all the repairing of wires, changing coils, and (where is the 12V source now? MSDs are very susceptible to power source...) overall sensitivity, your MSD box may have been 'compromised'. Try a standard points distributor with the 12V Ford coil. (just for a test)
All the wire connections I fixed where exactly the way they where. I just added metal***** connectors and heat shrink so they weren't taped connections
Gonna try a different coil tomorrow as well as cleaning carb agin and all the fuel lines regap plugs to .035 and possibly new set of points
You might check your float level while your at it...symptoms suggest that may be most of your problem.
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