All Choked Up
Neal Zimmerman, Eugene OR 1963 plymouth belvedere 318 poly
What typically brings on flooding conditions?- My 318 poly with Carter four barrel just started doing the flooding thing, gas smells,long cranking required, super rough idle, generally dies when dropped into gear (Automatic), black sooty patches on driveway, Thanks
This is probably NOT really flooding, which is generally a condition where raw fuel literally POURS into the engine, usually that’s caused by a stuck needle and seat in the carburetor. What you’re describing is simply and over-rich condition. On pre-’65 Mopars, this was common – the choke unloader mechanism was a piston-type deal in the carb. The close clearances just needing a little gumming up to stick the choke almost fully closed. The’65-up external diaphragm fixed this forever.
If I’m right, a good shot of Gumout will fix this up quickly. A pre-emptive strike of the same, about twice a year, is a good idea.
Other possibilities include:
> Stuck manifold heat control valve (in the open position)
> Clogged crossover passages
> Choke thermostat totally shot
> Stuck choke blade
The above four items would apply also if you’ve updated to a post-1964 carb.