Islandia with Mercury EFI 240 M2 Jet Drive PLEASE HELP

[Rubcuev]

Hi guys, this is my first post here. I refrain from posting until I've thoroughly exhausted all my resources and have searched over and over again. I acquired 2002 Bomardier Islandia about 1 year ago and have had this same problem. I've been on the water for the last 2 days and will be here for another 2 days (at the river) so it would be nice to get some troubleshooting pointers.

The issue ONLY happens after I pull a towable and sit for a while. The boat will fire right up, but stumbles on acceleration. I'll apply full throttle, It'll reach 4,300 RPM's with out trouble, but then slowly stumbles to max RPM.

After reading several pages here, I replaced the TPS and port side head coolant temp sensor, but to no avail. The boat runs fine all other times, only happens after I tow.

Any help will be greatly appreciated. Thank You

-Ruben

 

[philipmurphey]

I would check for fouled spark plugs and replace as needed.

 

[Rubcuev]

Gonna replace them right now and go launch. Will report back in a bit.

 

[Sportster-2001-951C-Stock]

Yep, always look to plugs 1st. The other idea that pops into mind is there could be some water in fuel tank. Pour the spin-on filter into a clear bottle and let it settle.

 

[Dr Honda]

Once it gets to top RPM's... and clears out... is it ok after? Or... is it always rough on the top end?

 

[Rubcuev]

It will continue to stumble. I usually pull out of the water right after this happens.

I replaced all the spark plugs yesterday, the old ones were pretty fouled up. I launched right after. Waited to use the towable towards the end of the day (didn't wanna ruin the day so early, since this only happens when I tow).

This time after I towed, I didn't shut the engine off. I wanted to dissipate any excess fuel or oil before shutting down. I cruised for about 5 minutes and shut the boat off to prep my anchor. Well when I went to turn it back on, it didn't start. Sounded like the engine was flooded (from what I've read on here, this is a common problem)

Thanks to all the info I read on here, I didn't panic because I knew it would start up as soon as it cooled down. After it cooled down it fired right back up and ran flawlessly.

I'm now wondering if I should replace the temp sensor on the starboard side?
I'm about to go launch again right now, I don't think I'm gonna tow today until I get this figured out

Can I use the sensor on the port side on the starboard side? Are they the same?

Thanks for all the help guys, I really appreciate it.