Got a question for all you guys with jets, I figured there would be more knowledge here than most other places.
I have a 86 Johnson 70hp (55hp) outboard and am constantly having issues with it. The new problem is this: The motor fires up and runs great, everything seems to be working fine. I run the boat at full throttle for about ten min. and it soon starts to shut down and will only run at about half throttle. It seems that only 1 or 2 of the 3 cylinders is firing. The motor runs, and seems like it wants to fire back up to full speed but wont. If i let the boat sit (motor not running) until it has completely cooled down (a few hours) then it will run fine again for ten min. and then do the same thing. I took it to a mechanic and he said that my power pack is probably bad and so it is shutting down cylinders once it heats up. I am going to see if a have spark to all my cylinders tommorrow, which if not, would indicate that the power pack is bad...I think! I was wondering if any of you guys have any info on a problem like this.
Thanks for the help- hope everyones season is going well.