Tohatsue 9.8HP 4-Stroke won't re-start.

I have a Tohatsu 9.8 HP 4-Stroke that I do not use very often - Probably 50 hours since new in 2006.

Yesterday, I put my dinghy in the water and the Tohatsu started right up. Let it run for 5 minutes or so and all seemed fine.

I pulled the safety key to shut it off and then restarted it. Started great.

Took the boat for a spin... probably 15-20 minutes without a problem.

Came back and pulled the safety key to shut it down.

Within a minute, I tried to restart and it would not restart - Choke off and throttle opened a crack.

Re-primed the fuel, made sure the fuel hose was connected properly on both sides, made sure the engine was in neutral, added choke. The fuel is fresh and the air inlet was open on the gas tank

Would not start. This went on for 10 minutes.

Figuring that I might have flooded it, I waited an hour and it would still not restart.

Boating day over.

Given that it had been running perfectly just minutes before it stopped running, I am confused?

This morning, I went to start it and it started right up. Now I really don't trust that it is dependable.

By the way, 2 weeks ago, I changed the motor oil and lower gear oil.

Any ideas?

So, did you test for spark? Did you check to see whether the plug was wet or dry?

Thanks for the help.

I was on the water so didn't have tools, but did check that the spark wires were firmly attached.
They were.

The weird thing is that the engine started and ran for quite a while and then would not start.

I'm not sure how I'd loose spark or how the spark plugs would get wet in the time from when I stopped the engine to the time I tried to re-start it a minute later?

If spark plug was wet,usually weak or no spark. dry plug probably insufficient fuel or no fuel going to the cylinders. Answering our questions with a question doesn't get yours answered. please answer our questions,we are trying to help

Sorry about answering a question with a question.

I don't know if the sparkplug was wet or dry.

I will be sure to have tools with me when I next have the problem and will report the results.

Thanks.

I had an outboard that did this. Turned out to be a blown head-gasket. Would start, run fine and strong when cold but as soon as I shut it down warm would not restart for anything! I tried, carb, fuel, plugs, coil, nothing fixed it. Had reasonable compression when cold (which is when I checked it) so that was over looked for a time until one day I noticed it pulled easier when warm. Did your motor ever get hot, because that will do it? Is the water pump strong? I'd have a look at the compression both cold and hot.

The water pump is strong and I don't believe that the motor ever got hot. I will check the compression when I next get to the boat.

Thanks

Joe To see if engine is running at normal temp. Place hand in the telltale stream,if you can hold it there indefinitely she's fine. Another test would be hold hand on cylinder head for a six second count without scorching fingers your ok. Or new school an infrared temp. gun on head roughly 160 degrees

So I came back to the boat today, still without tools.

Motor is running great!

Started it multiple times.

Ran it hard to get it warm. Stopped it and it started right up.

The water that is exiting the engine is cool to the touch.

Still think there must be a problem but no evidence of it today.

If it isn't broken, it will be very hard to fix.

Exactly!