I bought this motor a couple months ago for cheap. It sat for many years, but was supposedly running when stored. I took a flyer on it since it had good compression, and I had a complete parts engine for it(77 115). I ended up needing almost the entire parts engine to get it running. I replaced the starter, starter solenoid, rectifier, coils, power pack, choke solenoid, plugs, lower unit, fuel pump and lines, and rebuilt the carbs. After all that it started right up and runs great on the stand. When I put it on my boat, It ran great for about a half hour. The second time I went out, after about ten minutes it started dropping rpms from 5000 down to about 4000 in a very cyclical manner. It keeps repeating it over and over like it's programmed to. If I keep it under 4000, it runs almost perfectly. I just had a similar issue with my 1994 140 Johnson, but that one would sputter out at high rpm like it wanted to die. This one does it in a calm and predictable manner. Just smoothly lowering in rpms and then going back up to WOT. I have tried multiple fuel tanks, although it doesn't feel like a fuel issue. I haven't replaced the stator or timer base yet. Could one of those be a possible culprit? I have since picked up an additional parts engine(76 115), so I still have a bunch of parts on hand.
Stephen
Stephen
