carburetor "downgrade"

[Plow Boy]

I have a 1979 F150 fwd C-6 with a 351M engine. The carburetor is the original 2150 and has all the original plumbing still attached. About 3 years ago, I rebuilt it and it ran great. Last winter I could not get it to run right as it wanted to stall whenever I let off the accelerator. The truck is a dedicated plow truck and is used only in the winter for plowing. It is not licensed for the road. I would like to return the truck to the simplicity of a '66 352 with a 2100 carburetor. Can this be done on the '79? If so, what do I retain as far as vacuum lines and what can be eliminated? I'd also like to raise the carburetor an inch or so to allow more clearance for adjusting the idle. Are spacers for a bbl available? I'd also like to run an open paper element air cleaner and remove the heat tubes, etc. that are currently on mine. Fuel economy is not a concern and the truck is always warmed up before it is put to work. As it is now, it starts immediately and runs fine until I let up on the gas.

[fastEdsel]

I had one of these engines in a '79 LTD 4 door sedan. I bought it new. The engine was right for the time and just adequate enough to get it from the production floor of Ford to and through the delivery system to the dealer lot. But the carb was equipped with an "anti dieseling" solenoid on the left side of the carb. This is the unit to set the idle of the 351 and when the engine was shut off the solenoid would disengage the idle and drop the throttle plates to a fuel cut off position. Quite annoying but they did work. I think if your carb is equipped with this solenoid it may have failed so when you let off the throttle it goes to the fuel cut off position. The solenoids are adjustable so I would just screw it forward and use it as your new idle position. Don't go change engines for something that could be such an easy fix. If there is no solenoid then I would survey the actual idle screw, it may just be laying on your intake manifold. They can fall out but most are held in place with a spring that puts pressure to keep the screw in place. Keep us informed.

[colnago]

It could also be as simple as a clogged fuel filter. In fact, I just changed the cartridge in my mechanical fuel pump, and the bowl was full of gunk. As far as vacuum, on my 352, I run manifold vacuum to brake booster, PCV valve, C6 tranny, and in-cab vacuum gauge. I run ported vacuum to the dizzy vacuum advance can.

Joseph