Engine will not run at low idle and is burning through gas like crazy.

[Coddy]

Engine will not run at low idle and is burning through gas like crazy.
I finally got my motor (1972 45HP Model 457HD) running this weekend. I had to work on the ignition system a little bit to get it running. I cleaned and re-gapped the points then replaced a bad condenser. After setting the gap to 0.015? I synchronized the carburetor to the ignition per the service manual (this involved adjusting the stator plate at WOT).
I think I solved the ignition problem since it started right up.
The problem that I?m having now is that it will not run at a low idle. Every time I try to bring the RPM?s down to a reasonable level, the engine stalls. It is also sucking up the gas like CRAZY!
This seems to me that it is most likely running rich. Is this theory correct? If so, how do I adjust the mixture? Thank you.

 

[DukeDelago]

Re: Engine will not run at low idle and is burning through gas like crazy.

You need a compression test first

 

[Frank Acampora]

Re: Engine will not run at low idle and is burning through gas like crazy.

First, regap the points to .020. Next look for a sticking inlet needle on the carb or a very high float level causing it to run rich.

Finally, at the top front of the carb is a low speed mixture adjusting screw (needle). Start with this screwed out about 1 or 1 1/4 turns out from lightly seated. Screw inward 1/8 turn at a time with several seconds in between adjustments for the engine to stabilize. Adjust until the engine sags or dies lean. Now go the opposite way until the engine breaks up rich. Set the needle midway between those two points.

NOW: On the water do a hole shot--full throttle acceleration from a stop. If the engine sags then picks up it is too lean and you must richen the needle. If it burbles then clears itself it is too rich.

Under any circumstances do NOT set the needle to less than 3/4 turns out. To do so will cause melted piston(s).