Re: Grey Spark Plug Scum
Don't let it get ya down. You'll get through it. At least you haven't pulled a head and found major damage like some other folks to visit. If all your problems can be taken care of with some advice from the good folks here at iBoats, a handful of gaskets, and a spare tire or two consider yourself blessed....

. Hang in there.
Well blessed I be!!!
I just couldn't sit around here and do nothing so I went ahead and put the smaller tire on the trailer and hit the road. Put her in the water, warm-up lever up, choke switch on, and I turned the key. The strangest thing happen and I need someone's help to figure this out. When I did those things, the motor started up and then ran. Turned the warm-up lever down and it still ran but at a lower rpm. Put it in reverse and the boat moved backwards until I took it out of gear and then the motor just sat there and idled at about 650. What the heck is this?????? Is the motor supposed to start on the first crank and then just....run?
What will I do with all that free time now that I don't have to sit at the dock and throw a tantrum?
So you all get the idea here by now. It worked. Now the big test, I ran it cautiously up the river for about 1/2 mile slowly (no wake zone) and then at a moderate speed (15-20mph). I can only use the speed from my depth finder (paddlewheel) as an estimate. turn around and back to the dock. check the timing on the lower end to make sure I had 5 degrees when the cam roller lined up with the top notch on the cam follower. It did. Pulled #3 plug to look for grey, not there. Took the boat back out and slowly bumped up the throttle until I was maxed out. RPMs only about 3200, estimated speed about 35 heading into a 10-15 headwind. Turn round, back to the dock doing the same thing but keeping the throttle below WOT (just in case something was wrong). Pulled the plugs and they looked good. Pretty much like automotive plugs, Maybe just a tad of film on them.
I took her back out and took it WOT,this time maybe 3500 rpm and a little faster. On the downwind leg I was able to hit about 4100 rpm and speed was 45. But I noticed some surging in the rpm gauge when doing this. It would shoot up about 200 rpm but I could not here the engine surging to match. Anyways after all was said and done, back on the trailer, checked the plugs and they looked good. Interesting that the rpms were higher on my downwind run. Does this mean prop issues or still some low HP issues?
I used up about 2.5 gallons of gas doing this, which seemed to be much worse gas mileage than I am used to. And the engine just seemed to run a bit rough. It definitely did not purr. It's a giant leap forward but I still would not trust taking it out very far without a buddy boat nearby to tow me home.
Maybe now I can take it back to the person who gave it a tune-up and ask him to fine tune it from here.