84 Merc 50HP Midsection exhaust

Hi folks, I have used your help with carb work and it helped my motor run better.

Lately I have started having issues again and have tried adjusting idle mix screw but cant seem get it past 4500 rpm.

I have soft spots on deck and know its and issue and prob have some exhaust blockage.

Lately I have noticed more exhaust coming out underneath powerhead from front of motor as well as some water.

is it time to lift powerhead and replace gaskets?

2-stroke


thanks!

`The exhaust tuner below the powerhead has been known to plug with carbon.

racerone said:

`The exhaust tuner below the powerhead has been known to plug with carbon.

Click to expand...

yes, thank you, ive read here you have posted that before.

Plugged tuner, equals, lifting powerhead to clean? ive read it does but hoping there may be a miracle substitution....

thanks!!

Well ----remove lower unit and inspect from below !

Ok all so there was a bit of exhaust in tuner, nothing crazy
boat is still running like it’s on 3/4 cylinders (my personal thought)

I’ve done compression all good, spark plug test all good (tested earlier this year)

as a troubleshoot I’ll ask this:
when finished running what my full throttle is, 4200 rpm at the moment

spark plugs were all hot to touch except the lowest plug which was Luke warm, plug had carbon but you can see more porcelain compared to other, but the temperature was unlike the other 3

Any thoughts on this?

thanks