I am having an electrical problem with my 1996 Johnson 90hp. (I'm also having fuel problems, but I think they are separate... will ask in other post.).<br /><br />I have had to jump-start the motor to get it started. Once it is up and running, the motor purrs beautifully, then dies after a while... at that point, the batteries are too dead to start it again.<br /><br />I just went and checked and one of the batteries failed a load test, so I replaced it. I was hoping that this would be the end of the problem. Also got a charger and topped them both up.<br /><br />Following the various posts on checking the rectifier, I put a meter on the battery and started it up. Unfortunately, I wasn't able to ge the motor running smoothly (due to the fuel delivery problem, I hope)... How soon after the motor starts should the voltage increase if the motor is charging the battery properly? At any rate, the voltage did not go up above what the battery was delivering before the motor started.<br /><br />The tach also doesn't work while running. Just as the motor dies, the tach jumps up to 1000, then drops again.<br /><br />I followed the instructions from the shop manual and various posts from the archive, and tested the regulator/rectifier excite and sense circuits... I had voltage on the purple lead from the rectifier with the key on, so nothing obviously wrong there.<br /><br />I also measured the stator resistance; according to the manual, I think I should be seeing 0.175-0.195 ohms... I measured 2.5 ohms across the yellow / yellow-grey leads to the stator. I did not find a short to ground on the stator.<br /><br />My questions: <br />Does it sound like I need to replace my stator assembly? Do people think I have checked it correctly? Is this a big job or something that I can follow the manual and handle?<br /><br />Is there any way to tell whether the rectifier is also bad without replacing it? Apparently, for this model, the rectifier is about $200, so I'd rather not swap it just to see.<br /><br />Could these sort of problems cause the motor to run rough? I suspect that is all related to a fuel issue, but thought I'd ask. A week ago, it was running smoothly when it started, but still wouldn't stay running.<br /><br />Thanks a lot for any help. This is driving me nuts.
