'84 70hp Johnson Bogs out when throttled up.

Hi All.

I bought my first boat last fall with a 70hp Johnson, great deal it started fine and everything was good winterizing it, maybe a little too much fogging spray but that was it. This year I brought it out on the lake, it was a little hard to get going at first, big cloud when it did catch but aside from that it ran well. Topped out at 32mph so I was rather pleased.

I had a couple of issues starting it after changing tanks but got it going again for another run around the lake. The real problem started when I had 4 guys in and went to throttle up, it just bogged out and barely got past idle speed even though it should have been wide open.

I didn't know at the time to try to pump the primer ball so I'm not sure if that would help. I figured I would change the fuel filter and the plugs just to start off with.

Any advice as to the best place to start would be helpful, unfortunately a mechanic is not in the budget at this point so hopefully I can figure it out with the help of the community.

Thanks
Greg

Re: '84 70hp Johnson Bogs out when throttled up.

Start with a compression test and get your max rpm verified (empty boat).
Most likely, and hopefully, you may solve the most with a carb clean and re-build.