OK. Got my boat back from mechanic and it's not running any better. Starting to wonder about his abilities.
Subject: 1977 115 hp Evinrude
History: Motor idled a little rough and under medium acceleration it would vibrate my CVX 16 until about 2800 - 3000 RPM. WOT at 5500 RPM was pretty darn smooth with just a tiny miss. Took to mechanic and he rebuilt carbs, new plugs and compression check. Highest cylinder was 135, 130, 125 and 120.
Took boat out today and it still idles rough. Seems worse. Not as much vibration under acceleration but there is a bit of surge at 5000 - 5500.
OK all you mechanics out there. I noticed that one coil was changed at one time. Reason I'm mentioning this about the coils is that my car had the same type of performance issues and it was one of the coil packs that was knocking on deaths door. It was week and about to go. Changed out the failing coil pack and it was like night and day. Also had one bad plug wire.
After 33 years, is it possible that the coils are heading south and could be causing these problems with the 115. Seams if it was having weak spark it would cause the same issues as my car was having. I can replace all four for about $130.
What does the group think here? What else should I consider?
