1995 Johnson 30HP electric start running very rough issue

[xoibsurferx]

Issue 1: My father has a 1995 Johnson 30HP electric start outboard that's acting up. We run 87 octane with quality 50:1 tcw-3 oil and the motor has brand new spark plugs that are what's required to be in the engine. Let me start by saying it used to run great until my father took it to the marina to have them replace the impeller and ever since its ran rough. It starts out running very slow and rough acting like its running off one cylinder or bogging down, etc...Just not a happy two stroke. After about 20 minutes of going slow at wide open throttle, messing with the choke, and messing with this red lever on what looks to be some fuel pump accelerator (I cant find a picture or anything of this mechanism but my 1984 johnson 25hp doesn't have it). It suddenly clears up and runs great the whole time we're on the lake. Until the next day when you try to start it. It even runs perfect after the ride home and we're flushing it. But if you wait until the next day and try to flush it then it does its running rough mess.

Issue 2: After the motor clears up from running rough and as the day gets hotter on the lake we run the motor and it acts like its running out of fuel and will actually cut off until I pump the ball. If I keep pumping the ball every two minutes or so it will stay running. I've tried running with the fuel cap off, cracked more, etc...Maybe thinking its just a fuel tank venting issue but still does it. Any ideas? Could this be related to my rough running issue? During this time where it wants to cut off until I pump the ball it runs great.