We sell a couple of products at work (our Marina) that our techs use alot of to do just that. One goes under the common name of "powertune", and you remove the aircleaner, bring the rpms up a little, and keep injecting this spray into the carb throat. The engine will want to die, but you keep playing with the throttle to keep it running. You pretty much inject the whole can into the engine, and just before the can runs out you shut it off and let this stuff soak in there overnight or so. When you start it the next time all this crap will blow out of the tailpipe (carbon) like you have never seen. Various marine manufacturers sell their own brand of the same product, (Mercury has one, OMC another, etc.)

The other product is Yamaha "Ring Free"> You put this into your gas tank and run it continually to keep deposits down. There are different doses to either just keep the system clean, or in higher concentrations to "shock" treat the system. Our techs swear by both, and I run ringfree in my Jeep truck because it is on it's last legs and I can feel the difference in power from running it.

I even used the power tune in my riding lawnmower and it made a much better running engine out of it after the treatment.


Don