Have Boat Questions? Ask a Boat Repair Expert.
Hello Jason. My name is Tan.
This is a sign of an ignition failure. Do you have a timing light?
Could I get the engine model number also?
Ok what we need to do to start out with is check spark on all cylinders with the timing light. The way to do this is connect the timing light to each spark plug wire run engine and watch the flash of the timing light. The flash should be steady with no dead spots. If you find a cylinder misfiring swap that coil with a known good firing coil. Does the misfire move? If it moves the coil is bad if it stays then we have another ignition component failing.
If you have no misfire then you will have to do this test on the water running the boat.
Can you do these checks and do you understand the procedure?
Do you have spark on all cylinders when you pull each plug wire? Does the engine slow down on each cylinder when you pull the plug wire?
Ok did you do this test when the engine was low on power? Have you tried choking the engine when low on power or squeezing the primer bulb?
Do this test advance the throttle and watch the timer base linkage. Does the timer base move when you advance the throttle at the same rate?
From your description you have an ignition issue. The choke and the primer bulb test eliminates fuel delivery. We really need to do the timing light test. So far by your tests there is nothing wrong with your engine. You have spark, fuel and compression.
Nope. The only thing the key switch does is turn the starter and ground the ignition. The rest of the wires to the engine are for the choke and the instrumentation. So the only thing that would cause an issue with the key switch wiring is the stop circuit. If that was an issue the engine wouldn't start.