[rick powell]

I checked the timing on the motor and it appears to be 6 to 8 degrees off. How do you adjust timing? Motor runs rough at idle but good w.o.t.

[HighTrim]

How did you check it?

Look at the FAQ and find a thread by Joe Reeves regarding this.

What is your idle set at? Should be 650 to 750 RPM under load in gear. When was the carb last bathed and rebuilt?

[rick powell]

put timing light on top right hand cylinder, started motor put in gear idling around 800 rpm's. Carbs have recently been rebuilt.

[HighTrim]

Was the low speed jet removed and thoroughally cleaned? Try a couple tests. Will spraying pre mix fuel into the carb throat pick it back up again? How about choking it?

Here is the link I was talking about before.

http://forums.iboats.com/showthread.php?t=228183

[rick powell]

I put new jets in everthing cleaned, high speed jets cleaned. Motor acts like it got a miss in it at idle. I've checked spark it's getting a good 7/16 spark on all cylinders, compression test good low 112 high 120.

[HighTrim]

Spitting back, sounding like a mild backfire, usually indicates a carb slow speed restricted jet..... something causing a lean carburetor scenario.

If you can't find anything wrong with the fuel system, maybe consider a leaky lower crankshaft seal, letting air to the lower cylinder and resulting in a lean sneeze of the lower. Cant really think of anything other than those two.

[Dhadley]

A very common place for an air leak is the side plates on the carbs.