View Full Version : Merc 115 Horse ongoing problem
walkersteelhead
09-24-2004, 05:51 AM
A friend of mine has a 115 horse merc 2 stroke. It has been in and out of the shop more than he wants to remember. The problem he is having is that it seems to lose cylinders. When he takes it into the shop they have replaced I believe what are called the spark boxes. One the first time it went in then the other one the next time. It was running great till last weekend after trolling then going back up river a couple of times to get back into the trolling lane it started acting up,having the same symptoms. Anyone have any ideas he is getting tired it being in the shop.
walkersteelhead
09-25-2004, 04:05 PM
bump
Boat Doc'
09-27-2004, 06:57 AM
assuming it is not losing spark in order of what is most common, plugged carburator, leaking water jacket or bad reeds. If the problem is intermittent I would expect electrical.
A friend experienced a similar problem and we were stumped until we happened to be working on it in the evening. As the sun went down and we found ourselves fiddling around in the dark, we were able to see an electrical short arcing from a wire to the engine block. One new wire and all the problems went away. Motor runs like a champ now.
Just a shot in the dark(pun intended), but it would be worth checking out! Best of all it is free!
PATRICK 11-14
09-28-2004, 08:38 PM
Sounds like you might be running rich? A bad float or idling for extended periods of time on upper hp motors tend to load up and foul the plugs! Does it cough, spit and sputter after trolling for any amout of time? Do you run it for 10+ minutes at half to 3/4 up to clear it out and its fine?
Might start with a hotter plug if you are going to troll with it. Just through experience! :cheers: