mid range power/power in and out

[flangler]

So, i jus recently converted my 20hp Evinrude(93') to a 30 hp. All went well. At that time I replaced the tank, all fuel lines inside the cowl and out, added a water fuel seperator, rebuilt the fuel pump, and rebuilt the carb. Ok and also added a inline fuel filter. Ok, so what is happeing is when throttling up to WOT. I advance the throttle and it takes a moment for the engine to respond, then once I full throttle it, it stays at the same rpm and slowly builds power. It doens't loose any power once at full WOT. It doesnt sputter at WOT once its there. If I give it full throttle sitting at idle sometimes it looses power and has shut off. Its hard to explain. Pumping primer bulb while operating has no effect.

I think its not getting enough fuel. It starts easy, every pull so I don't think it's flooding. Maybe a timing issue? I didn't advance timing. Possibly a clogged high spped jet?

If anyone could throw some helpful advice my way the would be awesome!

 

[Watermann]

Re: mid range power/power in and out

Sure sounds to me like a fuel delivery problem alright. Looks like you have gone through everything. Have you tried adjusting the jets yet? Give that a try before pulling them apart. I believe there is a faq on jet adjustment here.

 

[flangler]

Re: mid range power/power in and out

Well I actually just pulled the carb and looked in it and it was clean. Jet was clean and everything. I don't think you can do any type of jet adjustments. It looks like it is a fixed jet.

Even when I got home today and was flushing the motor, it wanted to sputter whem reving it. After I pulled the carb and started it again, it reved just fine. So, maybe it's just when its warm?