1996 Evinrude 9.9hp temporary reduced power/ RPM

When first started for the day my 96 9.9 hp Evinrude has reduced RPMs and power at full throttle for a few minutes. It will then suddenly rev up to normal speed and power. After a few cycles of this, it will then do fine and respond normally to increased throttle. It starts beautifully and idles fine except it will slightly accelerate while at idle for just a second then idle back. I have rebuilt the carb and changed plugs with no effect. Once it has been running for a while, it operates fine. The power pack was replaced less than 5 hrs run time ago (wouldn't start) Any ideas?

Re: 96 Evinrude 9.9 temporary reduced power/ RPM

It sounds like fuel to me,
remember all you need for a two stroke is
1.fuel
2. comp
3. spark
if you have all three it will run.
if you have good comp and spark it is fuel.

Re: 96 Evinrude 9.9 temporary reduced power/ RPM

Fresh fuel in tank. Is there a filter or screen that could be plugged or partially plugged somewhere. Maybe inside the tank? It doesn't seem like it could be a fuel pump problem because it starts immediately and does run normally at high speed after a while.

Re: 96 Evinrude 9.9 temporary reduced power/ RPM

It still sounds like a fuel problem, try pumping the fuel bulb when this happens and see if it runs better. if so, it's the fuel pump. if not I'm sure Joe will be along soon and will know what to do.

Re: 96 Evinrude 9.9 temporary reduced power/ RPM

It runs fine once it gets over the initial problem oftemporary reduced power and rpm and runs fine all day after that. It is just when first starting out. Even when it is running slow it is smooth. Just seems to be bogged down or something for a bit and then instantly kicks off and goes. It is not a gradual increase in power. It is instant. I haven't heard from Joe.