1989 30hp yamaha fouling middle plug

[basin1974]

I have a 1989 30ELH 30hp Yamaha that keeps fouling the middle plug, I rebuilt the carbs followed the set screw adjustments for each carb and still keep fouling the middle plug, could their be a leak in the fuel pump? its the same carb where the fuel pump is attached, or could a bad coil cause this also? Any help would be appreciated and if someone needs more info just ask thanks.

[99yam40]

Post up a pic so we can see what the plug looks like when fouled.

Rodbolt has talked about plugs before that were getting a small amount of water into a cylinder before.
but the extra fuel might cause a cylinder not to fire properly

ELH should be a 1987

[TownsendsFJR1300]

Did you inspect the fuel pump diaphragm for tears, holes leaks?

If not, you may want to, it's most likely your issue.

If original, it's almost 28 years old...

[basin1974]

I won't be able to post a pic, I am offshore till the 21st, I changed the fuel pump about 7-8 years ago and pulled and looked at it last time I was in, it didn't look bad nor did I see any tears but I did order another one. The best way I can describe the plug is that it is a lot more darker (almost black but no carbon) the the top and bottom cylinder are a lot lighter. I will change the fuel pump and order a coil and go from their, hopefully its one of those two giving me the problem.