97 Sea Doo Speedster twin 717's acting up

[Robmoo]

She just sat all last year and never got used. I put 5 gallons of fresh fuel in the tank to top it off, added some marine fuel stabilizer, made sure the engines would fire up, and took her out yesterday. Both engines fired up nicely, but then began to act up. They would rev up and then lose power. When I stopped the starboard engine failed and then wouldn't restart. I have valve installed to cut off the flow of water through the engine. So I cut of the water to the starboard engine and used the port engine to beach her. I couldn't get enough power to get her up on plane With me the DW and 2 DD's. We probably weigh about 650 lbs total and then there is some gear. I checked the fuel filter/water separators and it looked fine. When I fired up the engines to leave the starboard engine started, but stalled before I could let off the choke. I finally decide just to cut the water back off and use the port engine to get back to the ramp.

I haven't changed the spark plugs in a few years so I ordered replacements. I also haven't change the oil filters in a while so I ordered a pair of replacements. The engines acted a bit like they were being starved for fuel. If the engines were getting too hot an alarm should have sounded.

 

[Robmoo]

I think that I know the issue. I was watching a video of a guy tearing down a mukuni carb. It had a filter in it that was clotted with crud from the where the fuel lines had deteriorated. I bought the boat second hand back in 2004. As far as I know the fuel lines have never been changed. What do you bet that my engine are acting like they are starved of fuel because they are from these filters being clogged? Sound like I need to replacing the fuel line and pull the carbs and clean these filters.

 

[Beachbummer]

Those engines are super reliable and simple...but 99% of the time, it's the carb that will cause it to run like crap. That's a LONG time for those carbs. Mine usually needed cleaning/replacement every 3-6 years. I added dual spin on fuel filters in series to make them last as long as they could.

They can be had as a Mikuni model for around $200. If you have single carbs (like I did) it was worth it to just replace them.

Best of Luck!

 

[Robmoo]

What did you replace the original carbs with?

Those engines are super reliable and simple...but 99% of the time, it's the carb that will cause it to run like crap. That's a LONG time for those carbs. Mine usually needed cleaning/replacement every 3-6 years. I added dual spin on fuel filters in series to make them last as long as they could.

They can be had as a Mikuni model for around $200. If you have single carbs (like I did) it was worth it to just replace them.

Best of Luck!

 

[Beachbummer]

Same carbs. Mine was single carb mikuni bn-40-38-24 they are much cheaper through mikuni than through seadoo.

Here are some options from Riva. With some googling you can find better price.

https://rivaracing.com/b-88059-mikuni.html

Everyone thinks I'm nuts for replacing vs rebuilding, but I just have not had great luck with my carb rebuilds.