Flooded Engine Compartment - Engines Won't Start

[mrodz123]

So a bit of a late response here, but it has been a long journey indeed. I followed all the suggestions here and determined the issue was most probably the ECU. After everything was cleaned and dried though, I still could not get it going on my own, so I decided to take it to my local Yamaha dealer for service. I got it back in March.

At that time I was weeks away from my wedding so I was too busy to take the boat out for a spin, but I was able to check that the engines could start. This weekend I finally got to put the boat on the water. Engines started, everything looked good, but shortly after getting the engines started, and still on idle, the starboard engine threw an engine temperature warning.

Oil level looks good, and the oil is clean. I decided to go home to do some research and try again the next day. After lots of digging, I found a bunch of people offering the same suggestions — check the peeholes for discharge or change the plugs.

The next day I went back and install all new plugs. Started it up and still got the engine warning on idle. I wanted to check the pee holes and they don’t eject water on idle, so i took it out to the nearby channel just for a minute to give it just enough RPMs to check the discharge, but not enough RPMs where it would enter limp mode. Both pee holes did eject water, so i took it back to the marina.

So oil is good, new spark plugs installed, pee holes eject water (water cooling system is okay?) — now I’m all out of ideas. What should i check next? I don’t think it’s just a faulty temperature sensor, because the engine does actually feel very hot to the touch.

 

[swatski]

So a bit of a late response here, but it has been a long journey indeed. I followed all the suggestions here and determined the issue was most probably the ECU. After everything was cleaned and dried though, I still could not get it going on my own, so I decided to take it to my local Yamaha dealer for service. I got it back in March.

At that time I was weeks away from my wedding so I was too busy to take the boat out for a spin, but I was able to check that the engines could start. This weekend I finally got to put the boat on the water. Engines started, everything looked good, but shortly after getting the engines started, and still on idle, the starboard engine threw an engine temperature warning.

Oil level looks good, and the oil is clean. I decided to go home to do some research and try again the next day. After lots of digging, I found a bunch of people offering the same suggestions — check the peeholes for discharge or change the plugs.

The next day I went back and install all new plugs. Started it up and still got the engine warning on idle. I wanted to check the pee holes and they don’t eject water on idle, so i took it out to the nearby channel just for a minute to give it just enough RPMs to check the discharge, but not enough RPMs where it would enter limp mode. Both pee holes did eject water, so i took it back to the marina.

So oil is good, new spark plugs installed, pee holes eject water (water cooling system is okay?) — now I’m all out of ideas. What should i check next? I don’t think it’s just a faulty temperature sensor, because the engine does actually feel very hot to the touch.

Peepholes shooting water does not rule out cooling system obstructions but it does indicate your intakes work, so that narrows it down potentially.
Check out @buckbuck video on how the cooling system works in FAQs.
That has helped many members narrow down the issues.

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