Re: Mid 50’s Johnson 25HP runs like crap. Advice needed

[Don]

The water leak is sure a possibility, but I wouldn’t go pulling that exhaust cover off just on a guess. You could pull the gearcase and try to run the engine, but it will have no load or exhaust back pressure so it might just seem like it is running better….Run the engine normally, pull the plugs, look for droplets of water…Tap the plugs in the palm of your hand also, this helps show the water droplets…Again, I would not go pulling that cover unless you have more solid proof that water is getting into the cylinder(s).
I’m trying to remember which cylinder wasn’t firing correctly…I’m looking at your pictures again, looks like the manifold area that has the sooty residue belongs to the bottom cylinder. I’m making this judgement by looking at the way the crankcase is deflected "upwards" on the left of your picture, and "downwards" on the right….
So the reeds "look OK", are those rubber tank pressure valves OK? Seems like it is time to get back to basics before getting in "too deep".