342 with 5.7 and bravo III

yeti

From one weekend to next, top speed goes from 37 to 30.  Seems to have no get up and go, can hardly get on plane.  Bilge is empty of water.  New plugs and caps.  No vibration of note to lead me to believe the props are damaged.  Seems to be able to get no more than 4200 rpms out of port engine.  Considering 1) damaged prop (floats so I cant see it) 2) water logged hull (11 years old)  3) fouled bottom (painted every three years)  What am I not thinking of??

212rowboat

fuel filter, air filter, fuel pump... 

raybo3

Sounds like the bottom could be getting growth on it. Doesn't take much. How old is the gas? Gas filters? 

yeti

Gas is new, fuel water separators are probably 3-4 years.  Fuel filters never changed that I can recall.  Not sure where they are?

LaRea

That sort of "sudden onset" problem doesn't sound like bottom growth or water-logged hull.  Maybe a stick or other debris jammed in a trim tab or outdrive?  Line fouled in the prop?

Black_Diamond

Forsure change the fuel water filters. The fuel filter is in-line and should both be mounted on the firewall. 

Clean the spark arrestors too. 

A damaged prop would not limit engine rpm. Are your tachs working?  The Faria tachs are rather unreliable fellas. 

bottomline

 same happened to my 6.2 port engine ,turned out to be wires

J3ff

you said 37, to 30 new plugs and caps... so it was 37 and you put new stuff in and now it's 30? If that's the case put the old stuff back in!