Brand new rebuild on a stock 216, top to bottom. Just installed in truck and fired up for the first time. Carter W-1 carb is a newer professional rebuild (shortly before engine was torn apart, 3 years ago.).
Engine requires full time partial choke to run, at idle & high idle. After first warm-up, plugs were uniformly sooty (dry fouled). Smelled rich as well. Replaced plugs (finally got new AC R45s).
So I get that the engine is running RICH. Thursday, will pull carb and check float first and foremost.
Here's the question: Why does this engine NEED the partial choke to run?! The whole point of the choke, in my mind, is to reduce airflow/increase vacuum in the venturi to draw MORE fuel for starting. But THIS engine doesn't NEED more fuel - it's already OVER-RICH. (At idle, looking down the carb throat, I can see fuel percolating out of the jet in the center - not out the idle port.) Needing choke to run doesn't make sense to me. The two things - Running Rich and needing Choke to run - work against each other in my mind.
Here's my only idea:
The choke is providing increased air velocity which is helping atomize the excess fuel that is entering the manifold?!! Otherwise, the raw fuel wouldn't burn and it would flood?
Somebody School me . . .
-Michael
