Hi! looked everywhere for a solution but can't find this particular electronic problem.
Background: Recently acquired 97 SP that has exchanged hands a few times in the last couple years. Ran great for a half hour on the water and after stopping and restarting the engine a few times it wouldn't beep or start (fully charged battery.) 5A fuse was blown and kept blowing instantly. Found starter laying at the bottom of the hull and after bolting back on still nothing. figured mpem got fried due to a short from that situation and replaced with amazon aftermarket and worked great again. I think that is all unrelated to the next problem but threw it out there for context.
After the next flawless day on the water, it would die and beep twice exactly as if the dess key was pulled off, and would start right back up with the push of the button. After some diagnosis determined it would only happen if the rectifier either red wire or yellow wires were plugged in, or the black/red stripe for coil (would have to kill it with the choke in this case - i did it on the trailer not in the water im not a complete idiot). Runs perfect on battery only or with coil unplugged from computer. We ran it on the water for hours on battery only and tried to kill it but was fine. replaced rectifier, mpem(again), and stator in that order with no resolution. It also runs forever at idle. only tweaks out after bringin the rpms up either gradually or also going WOT but will die pretty much instantly in that case
My thoughts: the black/red from the stator must provide signal/power to the coil somehow. that same wire that continuse to the mpem must internally ground that signal somehow in the event the key is pulled of, start/stop is pressed, or it detects another condition it doesnt like. Was my replacement rectifier bad out of the box or am I overlooking something here? I don't have a DSO just a DMM but voltage looks good 12.5 when off and climbs steadily with increase in rpms but can't go that high before dying, ive only seen about 13.5v. I was hoping to see a big spike or drop that would point to a voltage issue but I'm totally lost without understanding the mpem logic i could really use some direction. Thanks!
Background: Recently acquired 97 SP that has exchanged hands a few times in the last couple years. Ran great for a half hour on the water and after stopping and restarting the engine a few times it wouldn't beep or start (fully charged battery.) 5A fuse was blown and kept blowing instantly. Found starter laying at the bottom of the hull and after bolting back on still nothing. figured mpem got fried due to a short from that situation and replaced with amazon aftermarket and worked great again. I think that is all unrelated to the next problem but threw it out there for context.
After the next flawless day on the water, it would die and beep twice exactly as if the dess key was pulled off, and would start right back up with the push of the button. After some diagnosis determined it would only happen if the rectifier either red wire or yellow wires were plugged in, or the black/red stripe for coil (would have to kill it with the choke in this case - i did it on the trailer not in the water im not a complete idiot). Runs perfect on battery only or with coil unplugged from computer. We ran it on the water for hours on battery only and tried to kill it but was fine. replaced rectifier, mpem(again), and stator in that order with no resolution. It also runs forever at idle. only tweaks out after bringin the rpms up either gradually or also going WOT but will die pretty much instantly in that case
My thoughts: the black/red from the stator must provide signal/power to the coil somehow. that same wire that continuse to the mpem must internally ground that signal somehow in the event the key is pulled of, start/stop is pressed, or it detects another condition it doesnt like. Was my replacement rectifier bad out of the box or am I overlooking something here? I don't have a DSO just a DMM but voltage looks good 12.5 when off and climbs steadily with increase in rpms but can't go that high before dying, ive only seen about 13.5v. I was hoping to see a big spike or drop that would point to a voltage issue but I'm totally lost without understanding the mpem logic i could really use some direction. Thanks!
