no power at WOT

[SamLin]

i have a 1987 omc 5.7 ltr (bayliner) last year I installed a new carb. new fuel pump and filter. I also changed the drive shaft in the out drive ( installed a used shaft with new bearing installed at a shop and I re assembled it) my problem is that at WOT im only getting 3500 rpm and only 14 mph. could this be because of the out drive or something else. im not the best at mechanical so please any ideas would help. thanks

 

[Scott Danforth]

when you installed the carb, did you make sure the throttle cable is adjusted properly and the throttle plates are opening fully?

 

[vinnie1234]

I'm not sure if boats are equipped with a high output version of the 5.7 Chevrolet engine, but most automotive versions hit redline at around 4-5000 RPM. If you are at 3500 RPM and only 14mph, i would be inclined to check the prop. Do you know what WOT RPM is supposed to be? If it should have more RPM, aside from throttle that Scott mentioned, you could have and ignition timing issue. If you have a misfire, you may also have a lean fuel condition.