I would inspect the head for warpage per Yamaha's directions.
If out of spec, you could have a few thou removed. In which case you might want to consider the use of a slightly thicker gasket.
When you say that it "seems to be" the charge coil, what do you mean?
You should be able to test the charge coil in situ to see if it is within specifications or not.
It is conventionally threaded. To loosen turn counter clockwise.
Flywheel is tapered. You will need a puller to remove it.
If you think the nut is tough to loosen, wait until you try to remove the flywheel.
Clogged carburetor may be the reason for no fuel to the number three cylinder. Mist some gasoline into the throat of the carburetor and see if that cylinder starts working.
A failed diaphragm on the fuel pump can allow gasoline to get into the crank case.
What kind of thoughts? Thoughts related to water in the oil? My first guess would be a failed gasket.
Now where is the water? Just in the lower cowling? Just in the oil pan? Or both?
1998 200 what? There are multiple 1998 200 models.
Why not use the Yamaha parts catalog to find a Yamaha part? Novel concept that.
I will make a guess.
