Late 90’s Johnson 25hp Half power

[Sontagshane]

I have a late 90’s Johnson 25 hp. I was going down the river and it suddenly went to half power and stayed there. I made it back to the ramp at half power. But now it will crank and idle at half power for a few seconds then die. And is hard to crank after that. Does anyone know what it may be?

 

[racerone]

Sounds like it is running on one cylinder.----New sparkplugs is worth a try.----Check for spark on both leads.