Have Boat Questions? Ask a Boat Repair Expert.
Hello Calvin. My name is Tan.
Have you checked the spark on the engine when it acts up with a timing light? We need to try to determine if you have a spark issue or fuel issue. The symptoms tell me an ignition issue. The only way to know is to run the engine and check spark when it is acting up. What you do is connect the timing light to #1 cylinder run the boat till it acts up look at the flash of the timing light. You should have a steady flash of the light. If no misfire move to the next cylinder. Continue till you have checked all cylinders.
If you have a misfire on only one cylinder move that ignition coil from that cylinder to a known good firing cylinder. Does the misfire move?
Can you do these tests?
Ok but is it acting the same way it did before? Do we know that you have a power pack issue again. You could have a stator or timer base issue that will tale out 3 cylinders at a time. So we still need to test to find out if it is a pack or something else. What I would do it take the boat out run it till it acted up. If we have 3 cylinders on the same time go out I would then swap the power packs. If the misfire moves then we know the pack is bad. If the miss stays on the same side then we have either a bad timer base or bad stator. What you would do next is test the out put of the timer base and the stator with a DVA adapter or peak reading volt meter.
Do you have the means to do these tests?