I am working on a 25 HP Merc with no spark, history-- did a service call for engine not running, found water in fuel, cleaned carb, lines and tank, ran great! A month later called again, engine not running good, found bad plug wire on top cylinder, cleaned corrosion, dielectriced ran great.-- Called again last week, won't start. I found no spark, in both cylinders. Any Ideas?? The safty switch is in RUN. This is an elderly couple with not a lot of money,so I don't want to just change alot of parts.
