Need advice on which is better for trolling. Lean or rich to keep plugs clean enough.

[cyclops2]

My 2 stroke 30 hp Evinrude loves the NGK 4322 hotter plugs. The carburetor idle mixture screw is air temperature sensitive. So I have fouled plugs sometimes. I carry spares cleaned up.  I can clean the stumbling plugs if I run at about 80 % power for 4 to 5 minutes.

The 1988 30hp  2 stroke  is a fantastic reliable motor.  What would help besides a drop down plate to increase drag as I raise the in gear idle speed.

[Way2slow]

If you get it too lean, it's going to lean spit, and that's hard on the reeds.  With the motor in gear, in the lake and with the tilt set so the anti cavitation plate set so it's level with the water surface (motor is vertical) and warmed up good, I adjust mine until it idles it's absolute smoothest.  Turning the screw in, until it starts getting a little rough, then back out until smoothest, then go out about another 1/16 to 1/8 turn.  Please note, direction you turn depends on the carburetor, some are air mixture which turn opposite than the ones that are fuel mixture.

I also run nothing but Champion plugs in OMC motors QL77 in that motor.  As you have found, it also pays to run WOT for a few minutes the clean the plugs after a long idle period.  Indexing the plugs helps a lot to keep them from fouling.

 

Understand, when I say level with the surface of the water, I'm not saying it's on the surface, it's going to be a foot below the surface, but it should be on a level plane with the surface of the water.   Also, if you put a small level on top of the flywheel, facing front to back, it should be level.

[cyclops2]

Many thanks on the level check. I have seen the term INDEXING used in car tuning.   Turning the ground electrode to a certain place in the cylinder. Where is my ground electrode TIP or thick base part to be pointing?  I have 7 new plugs with plenty of gasket to probably get the index definitely much better.  Than where it is right now with the crushed washer from cleaning the plugs so much.  The mixture is touchy. + or- 1/8 from smoothest in gear position. I can put a black Magic Marker where the ground electrode is welded to the steel ring.  

[cyclops2]

I have learned that slightly RICH is the best sett ing while idling forward. I can hear the complete smooth firings. ?  The speed is TOO SLOW. increased speed to be fast enoughso they commit from a reaction strike.   Life is good.  Trolled 2.5 hours perfect running and no hesitation whentime to speed up.  

[cyclops2]

Way2slow

 

 Thank you for the Indexing information !!!  The engine is as good as a FI. Better at idle than a F I.   WWAAAHHOOO

You are the best. Many thanks. It cured ALL cold idle starts & idling. Allows the smoothest and slowest idle possible. Instant acceleration hot or cold. NO color on the plug metal or insulator.

 

You are the best.  ? ? ?

[cyclops2]

I spent a 1/2 hour more on the indexing FINE TUNING.  It paid off I was about 45 degrees from the best setting possible.   I had used a old black, wet oily set of plugs. The best setting was OPPOSITE what looked like it should burn best.  Trial and more trial worked.  Idle mixture is stable enough with the throttle valve completely closed.   It runs great on either 50 or 100 to 1 oil ratio.