Tohatsu 9.8 HP 4-stroke won't restart.

[joevar]

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?

 

[pvanv]

Assuming your model is MFS9.8A3.
Did you check for spark?
What do the plugs look like (wet or dry, clean or black)?
What is the level on the dipstick?

 

[Sea Rider]

At restart while OB is still warm, throtttle grip must rest at idle position, if doesn's start after 2-3 max rope pulls, pull choke fully out, advance throtle grip to start position, pull rope vigorously one time, put choke back in, should re start right up.

Near all OB's tends to become tricky when at restarts. It's a matter of finding the right throttle/choke setting. If suspecting having a flooded OB, remove plugs, will look well wet, with a lighter ignite both plugs, let flame die, pull rope everal times before puting plugs back in, should start right up.

To stop OB, when throttle grip is backed to idle position and geared neutral soon after has run at speed for some time, do you hear a slight rpm increase compared to idle ? If so, let OB decrease rpm before shutting OB down or will have more fuel leftover on combustion chamber when at restart.

Happy Boating

 

[pro-crastinator]

I may be way off base here but I had a similar experience and found the problem to be (me) user error.
WHat I did was use a red safety shut off clip from a different manufacturer that worked fine until I pushed the red button to stop the motor, and the clip shifted a slight bit to where the motor would not start. Figured it out after a while.