Why will my boat only go 15mph?

[Crudd55]

I have a 2002 Outback and took it out last saturday and it ran great, then I went out 3 days later and it won't go above 15mph, and 3000rpms, I can rev the engine up to 5000rpms but as soon as the transmission is engaged it won't go like it should. Any ideas? Thanks

[jester]

How does the engine sound when it is running. When you are going 15MPH are you getting any vibrations? How is your oil pressure and engine temp? I think 3K is high for 15MPH.

[KSmith]

Do you have Moomba cruise? If so make sure it is turned off.

[DOCDRS]

How old are the spark plugs?

[KSmith]

Did you pull up the anchor?

Just a thought.

Sorry... couldn't help myself :D

[eseebeck]

sounds like moomba cruise is on to me.

[Crudd55]

Brand new spark plugs
no moomba cruise
the oil pressure is 40 and temp was 170
the engine sounds good but, sounds like it was struggling like it was using all its power to go 15
there were not any vibrations that i noticed

oh and the anchor was up:)

[kaneboats]

Did you examine your underwater gear? Nothing wrapped around the prop? Check trans fluid?