115 Merc, year, plugs, tips.....

[outboardkiwi]

Hi team, a friend of mine has just purchased a new ski boat with a 115 inline 6 Merc s/n 0A996094. We believe this to be a 1986 model, this that correct. Also I noticed the plugs were NGK’s BUHW, I remember someone telling me champion plugs for American outboards and NGK’s for Jap outboards etc. OK to continue running the NGK’s ? Any other tips on this engine would be greatly appreciated. We run it up today in my test drum and were very impressed, very smooth running engine, compression all 130-135, has only 340hrs on the hour meter, so hopefully should be a good one.

 

[phatmanmike]

Re: 115 Merc, year, plugs, tips.....

kiwi, mercs run top notch and are reccamended by dealers to run NGK plugs.<br /><br />i had a 1976 version of that same motor. the plugs should be flat tipped, no electrodes. no gapping required. perma gap! <br /><br />have fun with her!<br /><br />prop it to turn closer to 6000 and always run GOOD oil in it! she will thank you for it !

 

[outboardkiwi]

Re: 115 Merc, year, plugs, tips.....

Valvoline TC-W3 oil ok to run in these motors?

 

[rabidfish]

Re: 115 Merc, year, plugs, tips.....

That is better oil than was available while the engine was being produced. While I'd love to tell you to run the Mercury oil... You'll be fine.<br /><br />As for the NGKs, Myoutboards is correct, Mercury recommends and sells NGK plugs to the dealers. I have switched over to NGK for all but a few BRP applications.

 

[outboardkiwi]

Re: 115 Merc, year, plugs, tips.....

What do these Merc's have for an overheat warning. I am use to OMC outboards and the familiar horn test on turning the ignition key, which I didn’t hear when starting this engine.

 

[Clams Canino]

Re: 115 Merc, year, plugs, tips.....

Depending on the model - there may be none. You can have one tapped into the block just starbord of the #1 spark plug if you wish.<br /><br />-W