96 Evinrude 115 wierd issue

I have a 1996 Evinrude 115 on a 19 foot center console that has had a weird issue for about 7 months now I can't seem to diagnose myself or professionally.

When I plane out at around 4-4500 RPM after about a minute or two the motor will start to hesitate and RPM's will bounce up and down like it's starving for fuel or sucking air. I end up having to stop and shift into neutral and let it stabilize. Then go back to powering up and repeat the process. It'll happen every time after a minute or two on plane. Occasionally it will happen in rough water when bouncing over waves going slowly.

A mechanic said fuel pump so I had the VRO removed and a new fuel pump installed professionally removing the oil injection. All fuel lines were replaced at that time too. That didn't fix it.

I've also replaced the power pack under advisement from another person. Still didn't fix it.

Has anyone had anything like this or any idea's on how to fix this problem? It's getting frustrating to try and cross the lake having to stop every few minutes. I think it would be a waste to buy a new motor since the compression is good. Any help would be greatly appreciated.

Could be quite a few things:

- dirty or partially clogged main jet in carbuertor
- like you say, an air leak in the fuel pick.
- gas tank not venting. Maybe run off a different tank and see if it helps.
- stator issue
- trigger issue
- bad coil. If this is your max rpm, then probably not firing on all cylinders.
(use a DVA meter to troubleshoot all your ignition, or you could/will spend a fortune throwing parts at it)

I appreciate the info. That gives some things to check out. It's not the max RPM, I'm not comfortable running wide open so I tend to keep it between 4000 and 4500.

I found it very weird that it only happens like it does and it's stumped me.

Could also be the fuel bulb. You need to replace those every few years or they start leaking.

check to see if battery charging properly?

Thanks, I replaced the fuel bulb when the fuel lines were replaced.

Battery is charging... The rectifier was replaced too...

I seem to be dumping money in the water lol.

I would try a different tank like recommended that will at least clear whether it is a tank problem.

Should be able to troubleshoot this without spending much money. From the sounds of it, I'd think you could get this cleared up for $300 or less. And look at it this way, you haven't really dumped a lot of money in the water, you've just built up a nice inventory of good used parts....