115 problem

[Rj_]

I have a 2002 2 stroke mercury 115. It has an alternator driven ignition. The motor starts and runs fine initially. After a half hour or so, when running at any speed above idle, the motor will act like you are running out of gas. You can idle for a few minutes, take off again, and you might de able to run for 5 minutes or 30 seconds. The problem seems heat related, since I have never had the problem happen in the first 30 minutes or so.
i put a portable fuel tank with a new fuel line,bulb, and fuel on board to try to eliminate my fuel system with no help.
have inspected wiring from trigger and stator with nothing obvious. Does anyone have any suggestions on how to troubleshoot this problem? Thanks!

[boats.net]

You can use a timing light to see if all cylinders are firing when it slows down, if it does have a loss of fire then need to test peak reading voltage( will need a peak reading voltmeter or a DVA adapter to read peak voltage) output of stator, trigger coils and switch box output to coils to see which part has failed.

[Rj_]

Thanks! I will check the firing. I don’t have an attachment for my meter. My meter will store voltage peaks, but I assume this is not the same thing as what you are referring to?