loss of power??

[clutch3752]

Recently purchased a boat with a 2000 model 115 Yamaha four stroke. Taking it out the motor would not get up to past 4,600 rpm. I reduced the prop size and am currently running a 17pitch on it. Noticed a little increase in rpm, but did not fix anything. This time I noticed when taking off I could get up to about 5,000 at about 3/4 throttle, but when I cotinue to the console the motor drops rpm, sometimes to 4,600 and once I saw 3,800. Pull it back to 3/4 and I actually pick up some speed and rpms. Is this a vst tank filter and injector problem?? If it is, roughly how much is this going to cost me to get taking care of?New to the whole boat thing and just wanna get this right. Any help in appreciated,
Thanks
Scott

 

[rodbolt]

Re: loss of power??

clean the VST,replace all the fuel filters, send the injectors to flagship marine for cleaning and screen replacement.
do the work yourself and its 250 bucks or so.

 

[clutch3752]

Re: loss of power??

Thanks Rodbolt! Was thinking that was the problem after reading all the previous posts concerning power and rpms. I did just take the boat to a shop for a readout and we'll go from there. I don't have (and need) a service manual. I am pretty good with a wrench 30year Helicopter mech, any special tooling or concerns in doing this, how many man hours does the shop get??