No Power in the water,

[wink83]

i have a twin rotax jet boat, my left engine will run fine on the trailer, rpms will get up to 7k plus, but as soon as i put it in the water the rpms will not go above 5k and the boat barely moves on that engine, i have checked fuel and plugs and compression, took the back end apart and looked at what i could look at, what else do i need. i have had this boat for four years now and never an issue until last year, this caused me to go and buy another boat but i still have this one and want to try and fix it or sell it.
any advice would be great.

 

[mikidymac]

What is the compression?

 

[wink83]

Compression and all engine oil and fuel test were all good.

 

[PSBeachBum]

i have a twin rotax jet boat, my left engine will run fine on the trailer, rpms will get up to 7k plus, but as soon as i put it in the water the rpms will not go above 5k and the boat barely moves on that engine, i have checked fuel and plugs and compression, took the back end apart and looked at what i could look at, what else do i need. i have had this boat for four years now and never an issue until last year, this caused me to go and buy another boat but i still have this one and want to try and fix it or sell it. any advice would be great.

I am a new boat owner myself but my sportster (single engine) does the same thing at the same time and from what ive read this means its in limp mode. So that one engine is probably in limp. When youre in the water your speed sensor is at play and the computer is trying to limit your speed by keeping that engine at 5k rpm. Id read the codes.

 

[mikidymac]

None of the carb 2-strokes have limp mode.

Year and model would really help the OP.