Johnson 30 not rev up

[Sarrre]

Got a Johnson 30 hp 1990. It was running good until last ride. Then it doesn't rev up. I think it is running normally in idle speed, but it is just caughing when trying to rev up. Check video below. Hope you guys can help me.

https://m.youtube.com/watch?v=5Y6EKLnMVWQ

 

[flyingscott]

sounds like it's running on one cylinder and the other one is trying to kick in go to www.cdielectronics.com they have information on testing your ignition

 

[Sarrre]

Now I have some more information for you...
The compression test was showing good results, around 135 psi on both cylinders.
I attached a spark tester between the plug and the spark, and it shows normal sparks at idle speed on both cylinders. But when I try to rev up, the spark tester only shows sparks interittently on both cylinders. So there is ignition problem on both cylinders.
I tested with other coils without any change.

I checked the cdielectronics site, but it's hard to find information about my engine.

 

[scout-j-m]

https://issuu.com/cdielectronics/docs/practical_ouboard_ignition_troubles

 

[Sarrre]

I also got a 15 hp Evinrude 1990 which I borrowed some parts with same part numbers. So far I have exchanged these parts without any luck:


Ignition coils
Stator
Charge coil


However the power pack doesn't have the same part number on these engines, so I didn't dare to change this.
I followed the CDI troubleshooting guide, but I don't think my multimeter is able to read the DVA output properly.

But since I changed every part but power pack, could it be something else?

 

[Michawilden]

There might by some wiring which is grinding against the engine block. That can explain why it is sparking properly at idle but fails when the ignition plate is turning. However, if you changed the stator, the wiring would also change so it is unlikely. Google your parts number on your powerpack. You can find sellers which tell you that the powerpack is similar to other with different part numbers. Chances are that you can swap them since all other ignition parts are equal

 

[Sarrre]

Hey! I found out that it was the power pack! I tested with the 15 hp power pack and now it revs up as it should! So I will put it back on the 15 hp and order a new one for the 30 hp.