Lost power

Question
Question -
I have a 1998 115 hp Johnson Outboard motor. It runs but will only get up to 20 mph. Usually, it runs 40 to 45 mph. The throttle cable is fine and moves the engine lever to full throttle. My tachometer range 3 to 4 on the gauge or 3500 to 4000 rpms. I was told to check my prop,i removed it and the rubber seal seem fine. This proplem started shortly after i put a fuel addative in my fuel, that suppose to be okay for marine motors. Any suggestions on what the problem could be?


Answer
Hi Robert...Thanks for selecting the undersigned to reply to your question. Infortunately, you didn't mention the type/brand of the fuel addative.

I'm not mechanic but, if the engine was functioning fine before you introduced the product to the fuel, maybe that's the problem so, drain the fuel, refill, and see what happens. Have you checked the fuel line to ensure all connections are secure and the line isn't defective in any manner whatsoever? Are the reeds defective? Sometimes, a good tune-up helps. Best you consult a qualified and reliable marine mechanic who is familiar with OMC o/b mtrs.

Safe Boating
Ron