I recently had similar problems with my 60 HP Johnson. I'm convinced it had something to do with the engine monitoring system (ironically named SLOW). Below is a page from the owners manual describing the system limiting the engine operation to 3K RPM and "noticeable vibration". She idled fine...
***UPDATE***
Yesterday, in a last ditch effort before buying or borrowing a trailer and pulling the boat out of the water for significant disassembly (you can only do so much on the boat lift, suspended over 20 feet of water) I literally unplugged and plugged back in every electrical connection...
Thanks. I'll do a compression test this weekend. The spark plugs, plug wires and coils are all new. I swapped to the new coil/wire set and have the same surging issue as with the old set so that eliminates that part of the ignition system. Agree, could be upstream from there.
The Neutral Safety Switch? That is the only switch I recall around or on the shift linkage. It works...as in the boat will not start unless in neutral. I'll be back at the lake on Friday and will take a closer look at it though. Perhaps something is binding it during throttle up? Thanks for...
Thank you for the response. I'll try your suggestion. Did you happen to watch the video I posted on YouTube of the motor running? Hopefully that helps with my description of the issue.
New member here, looking for recommendations and advice for getting our boat running right. Thanks for taking the time to read my post and sharing any insight you might have. I share a lot of detail below so bear with me:
Background: We have a 2004 Johnson 60 HP, four-stroke, fuel injected...
