115 HP Jet Spark Plugs

I have a 1994 Four Winns Fling Jet Boat with an 115 Hp Johnson/Evenrude engine. When I bought it used it had NGK Br9hs 10 plugs in it. I am not sure if these were even the correct plug for that engine. I just replaced them with NGKBr9hix Iridium IX Plugs. I have not yet tried to start the boat. I have not read anywhere were this is not a good move, but i thought I would throw it out to the experts, before starting it up. Everywhere I read it stated that this was a great 2-stroke plug for sea-doo, yamaha etc, but they did not directly mention my engine even though somwhere it did reference this new plug as a match to the original plugs I swithed out.

Thanks in advance for your comments

Re: 115 HP Jet Spark Plugs

your motor is not a yammy, or seadoo, it is a J/E champion QUL77V. four winns and omc created the fling as a joint venture, and the only boat to use that set up.

Re: 115 HP Jet Spark Plugs

I have ordered a set of the plugs you said should have been in the boat? until they arive will I have any problems withthe plugs currently installed. I want to do some boating this weekend. I never had an issue with the "wrong" plugs that were in the boat when I purchased it this year.

Re: 115 HP Jet Spark Plugs

as long as they are not too long and hit the piston, you should be fine. all the OMC engines were built to run on champion.

Re: 115 HP Jet Spark Plugs

You can go to the NGK website and check these plugs for your self. I suspect the reach is ok but I think your heat range is off. The number ...in your case 9 referes to the plugs heat range. With NGk the higer the colder, 9 is a cold plug for sleds and MX bike stuff. Most outboards seem to be in the 7 range....close to cars heat range. I am playing with some NGK plugs in my 90 erude simply because I have used them racing bikes and sleds for 30 years and I like them. In your case I think I would wait for the champions or at least be real careful, if they are too cold you will prob just foul them anyway. Sell them to a biker or a sledder, actually one of my bikes and one of my sleds.....a ski-doo... use these plugs....lol .Then stick in the spec plug, better safe than sorry, esp when plugs are not a high ticket item, a melted piston is.