1999 40 hp Force loses power when warm

[jimdbob]

I am new to boat motors so please bear with me. I recently acquired a 95 Nitro16 TF with a 99 Force 40 hp 3 cylinder 2 stroke. It runs great out of water with muffs, so I put it in the water, idled out of the no wake zone, increased to full power and was tooling along for 5 minutes or so before we slowed to a crawl. Even at full throttle the speedo doesnt register, you can definitely hear the rpm's increase but not enough to get out of its own way. Spark is good on all cylinders when it won't power up. It will sit and idle no problem. It starts back up no problem, just doesnt have any power. A friend suggested perhaps the stator had failed. I pulled the cover off the motor once I got home and saw CDI stickers on the wires of both the stator and trigger with install dates of 2013, and noticed that a new voltage regulator and fuel filter had been installed pretty recently.

Any thoughts out there? I have not gotten into running diagnostics yet as I have been unsuccessful at replicating the failure on dry land.

Thanks for any help!

Jim

 

[foodfisher]

Rpms increase with no increase in speed indicates a spun prop.

 

[jimdbob]

Rpm's increase a minimal amount, and propulsion increases relative to the rpm's, It certainly is not full throttle though.

 

[SkiDad]

maybe the squeezie is going bad ? It doesn't sound like electrical issue if you have spark... if the stator was bad you would have no spark at all (at least my experience) I think you have a fuel related issue either squeezie, fuel pump or maybe clogged line or vent line. is the fuel filter clear if so you can see if you are getting enough gas. maybe try squeezing the ball again and see if it runs any better ?

 

[jimdbob]

the fuel filter is not clear, so I cannot confirm that. I think I will try to take it out again this weekend and try to troubleshoot the fuel system. Swap the fuel filter before I go. will advise. Thanks for the help!