Mercruiser 2.3L Goes rough at idel

[reavesga]

Motor starts easily but is rough. Bring the RPM up to 2000 on just the throttle and let it warm up and things smooth out. Bring the throttle back to idle and it is smooth but let it sit for a a minute or two and it gets rough. Kind of like something is hitting or misfiring. Advance throttle to 1000 and smooths out with no stumbling. Put it in gear and take it out and it is rough idling out of the no wake. Get clear of the no wake, put the throttle down and it smooths out with no hesitation and planes out fine. Sounds good. Come back to no wake. Bring it back to idle and it seems nice and smooth idling and then it starts to go rough like its missing or miss firing. Here is what has been done.

Compression checks. All good.
Replaced cap and rotor. No change
Replace plug wires. No change

Starting to suspect that I have a lifter bleeding down. Oil pressure while on plane 60psi. Idle 20-30 psi. Any help figuring this out is appreciated.

 

[superbenk]

Check your idle mixture on your carb. Maybe fuel delivery issue. When was the filter changed last? Could be a dirty screen filter in the carb or the carb needs cleaning.

 

[alldodge]

Sounds like you need to rebuild the carb, the idle circuits are clogging

 

[Bondo]

[h=2]Mercruiser 2.3L[/h]

Ayuh,.... I'm guessin' ya mean a 2.5l or 3.0l, as Merc has never used a 2.3l,.....

I agree with the above, it's much more likely the carb is the problem,....

I rather doubt the lifters have anything to do with the problem,....

 

[harleyman1975]

is it clacking at idle? that would be the tell tale sign of lifter bleeding down. I'm with the pack on this sounds like a dirty carb. the two brass tubes with the tiny holes may be plugged up. try poking through the little holes with a fine piece of wire...very carefully.