Fine tuning the timing on the water

[sparky4612]

I just completed a link and synch on my 1984 Mercury 115 i6 and was able to finally get it out on the water. Seems to run well but I'm not sure if there needs to be a little more fine tuning. It's an old engine so I'm not sure if the manufacturer specs are still the best fix. Can I fine tune the timing on the water at wot like I did the mixture? If so, what effect will advancing or retarding the spark have on the engine as it's running and what should I listen and look for. I've read about predetonation and that it's a bad thing but have no idea on how to do this by ear. Your help is alway appreciated, again!

 

[verado7]

Re: Fine tuning the timing on the water

let me put it this way - in the old days timing was set in a test tank or on the water - generally no mechanic will go out ans set timing on the water for obvious safety reasons - having said that i have always done it that way and yes you can -just pick a real calm day and go by the book spec -some engines will get a minimal gain -by advancing or retarding a degree or 2 but you have to be willing to accept possibly shorter engine life .