Rested Engine will start and run well but not restart after sailing

[heinz]

I have gone sailing a couple of times this year just to required a tow back to my slip because the engine did not want to start again. I have not been able to figure out what was causing it since the engine would start again the next time I ran it.
Does anyone have any thoughts what can cause this?

[Dave Neptune]

Heinz, we're going to need a bit more info. Have you done any trouble shooting? IE spark or fuel?

Could just be time for a tune up, how long has it been?

Dave Neptune

[joe_db]

Sounds like water getting into the engine.

[heinz]

Heinz, we're going to need a bit more info. Have you done any trouble shooting? IE spark or fuel?

Could just be time for a tune up, how long has it been?

Dave Neptune

Thanks Dave, I did a minor tune up at the beginning of the season and cleaned the plugs when it would not start. Regarding the fuel, I am not sure why fuel would be an issue since the engine runs well after the initial start.

[heinz]

Sounds like water getting into the engine.

Thanks Joe, I have not checked the oil yet but certainly will now. I presume if there is water in the oil it would prevent the engine from starting?

[ndutton]

What is your choke application practice for restart after sailing? Same as a cold start?

[joe_db]

Thanks Joe, I have not checked the oil yet but certainly will now. I presume if there is water in the oil it would prevent the engine from starting?

Not exactly. If water backs up into the engine through the exhaust, even a little bit will mean damp plugs that won't fire. Getting enough to get into the oil isn't good, but it is not the water in the oil that is preventing the engine from running.

[tac]

Ignition Coil Failure

Some of the common symptoms of a failing ignition coil are what you describe in post #1. After starting and running well for an hour or so, the coil heats up and the engine shuts down. Sometimes shutdown is preceded by a noticable missing on one or more cylinders for a period. After the engine shuts down, it often can’t be restarted for at least 20 minutes, until the coil cools off. When the coil cools enough to restart the engine, it will then shutdown again as soon as the coil warms back up. This can go on for many cycles before the final catastrophic failure.

There are a multitude of threads on coil failure and its solution; maybe the single most writen about topic.

[ndutton]

Re: Dave Neptune's post,

It would be really helpful if some testing can be performed during failure. An ignition system function test takes mere seconds and will point you (us) in a direction. Prior to leaving the dock, place a spare spark plug on the lifting eye. After a sail when the engine will not restart, have a crew take the helm, you remove a spark plug wire and attach it to the spare, have the crew crank the starter and you watch for spark. Yes spark = fuel problem. No spark = ignition system problem.

With this very quick and simple test you will eliminate half the failure possibilities and focus on what is really wrong.