It is a 2000 90hp johnson on a pontoon. I have replaced the fuel pimp, sparkplug, rebuild all the carbs and evap system. I'm kind of running out of things to try with this thing. After about 10 mins of roughly idling it shuts down and sounds like this video.
Found one of the vapor returns header lines on the side of the engine was partially pulled out. So now it runs, but is reving and coughing at idle. Still lean?
