Re: 70 johnson kill me
Welcome to iboats.
You'll get better response to your questions if you'll type 'em out as full sentences. Or at least, nearly full sentences.
With punctuation. And spelling. Us old boat guys haven't really adapted to "text" shortcuts. If that's the best you can do cause English isn't your 1st language then don't worry about it we'll manage.
Have you checked for spark on all 3 cylinders?
Done a compression test?
How old is your fuel? Any water or debris in the tank? Is the fuel line holding pressure? Is the tank vent open and clear?
Has it been like this since you got it, or it was running fine before?
Any other symptoms? Any other maintenance, apart from what you listed?
You said "runs great" about 10 minutes -- is that just at idle, or does it accelerate and run full throttle during that time?
What kind of spark plugs are you using?