tgundo2003
New member
Last year on the last run of the day the last day of the season like someone flipped a switch I suddenly lost about 1500RPM off the top end of the motor under load. It was the last day and it was going to storage, just winterized it and that was that.
About a month ago I pulled from storage, did routine maintence, changed the plugs, took it out and it ran great, no problems, so I figured I just had a fouled plug. I put a spark tester on all three plugs and had the same spark on all three. Took it out the next week while on vacation and had no trouble.
Well today, took it out, started my first run across the lake and again, like someone flipped a switch suddenly lost power. Local boat shop says it's likely a bad CDM module. It seemed like the bottom cylinder was the problem, it was cooler to the touch than the other 2....
Heres what I see after checking it out in the barn tonight:
Cylinder 1 & 3 plugs looked identical, wear, color, contact was dry.
Cylinder 2 plug was still wet, looked blacker, smelled of gas.
Pulled off all three CDM modules, did the diode and resistance checks per the chart, all three the same and all three checking out.
So- Given this info, it appears cylinder 2 wasn't firing. The question is if a CDM module is that intermittent, maybe when it heats up? How to figure out which one is bad if they are behaving? This motor really doesn't have many hours on it, it really only goes out a couple times a year.
Any advise or help appreciated!
About a month ago I pulled from storage, did routine maintence, changed the plugs, took it out and it ran great, no problems, so I figured I just had a fouled plug. I put a spark tester on all three plugs and had the same spark on all three. Took it out the next week while on vacation and had no trouble.
Well today, took it out, started my first run across the lake and again, like someone flipped a switch suddenly lost power. Local boat shop says it's likely a bad CDM module. It seemed like the bottom cylinder was the problem, it was cooler to the touch than the other 2....
Heres what I see after checking it out in the barn tonight:
Cylinder 1 & 3 plugs looked identical, wear, color, contact was dry.
Cylinder 2 plug was still wet, looked blacker, smelled of gas.
Pulled off all three CDM modules, did the diode and resistance checks per the chart, all three the same and all three checking out.
So- Given this info, it appears cylinder 2 wasn't firing. The question is if a CDM module is that intermittent, maybe when it heats up? How to figure out which one is bad if they are behaving? This motor really doesn't have many hours on it, it really only goes out a couple times a year.
Any advise or help appreciated!