1999 Evinrude 40 HP Surges / Skips at High RPM

[whalerdude24]

Ok, so I've had this strange problem with my 1999 electric start 40 hp Evinrude. I'll drop the boat in the water, go to the fishing spot, then when I try to change fishing spot the boat will surge or skip at higher RPMs. Typically when the RPMs are above 2.5k. It's a huge loss of power when it does it, and the boat hardly moves at all. However, the engine will idle fine, and if I engage the motor at very low speed like 1.5k to 2k, it can move no problem and the timing seems perfect. No misfires, or sputtering at low RPM.

I've cleaned the carbs twice. I believe it could be an electrical issue, but I don't know where to start. Any advice would be greatly appreciated. I've attached a video of the problem. In the video, you can see the boat idling, then when I raise the idle lever to higher RPM, you can hear the surging / skipping.

https://vimeo.com/190501151

Let me know your thoughts!

 

[racerone]

Test run with a " known to be good " tank and hose.

 

[jakedaawg]

I believe that is slow mode engaging but it a quick video and not under load.

Do you have any alarms sounding?

Does your.alarm beep once when you 1st Turn the key?

I suggest you run on 50:1 Mix until this is sorted out. A no oil signal and overheat are what engages slow on that motor.

 

[whalerdude24]

Hi all, sorry for the delay. I have used a different gas tank, and lines before only to find the same effect. I always use a 50:1 mix, since the oil mixer was removed from my motor. I'll try to find another video and post for you so you can get a better idea.

 

[jwall116]

Does it do this even on the first start of the day?

The video is pretty short but that that motor appears to be in a limp/safe mode. Something an overheat/no oil alarm would do.

I would start by testing the alarm system or disabling the alarm for a short test on the hose to see if it stops. There will be a sensor with a wire near the t-stats, try disconnecting that for a quick test.

When you first turn on the key, you should hear a very brief horn under the dash. If not, you could have an alarm issue.

 

[whalerdude24]

Does it do this even on the first start of the day?

The video is pretty short but that that motor appears to be in a limp/safe mode. Something an overheat/no oil alarm would do.

I would start by testing the alarm system or disabling the alarm for a short test on the hose to see if it stops. There will be a sensor with a wire near the t-stats, try disconnecting that for a quick test.

When you first turn on the key, you should hear a very brief horn under the dash. If not, you could have an alarm issue.

I'll try that this weekend, thanks jwall!