Here's the story... 2003 Merc 50hp EFI 4-stroke. At the end of the '04 season I did all the owner maintenance and storage routines by the book. I stored a 5-gallon can of gas with the exact correct amount of stabilizer. Last Spring to maintain the warranty, I hooked up the 5-gallons and went to the Merc authorized service guys to run their 200 hour checks and document the service for my warranty. But the stored fuel had gone very bad, and she ran badly til they launched and blew it all out with new gas. Nobody knows why that happened, so I figure that gas was pretty bad to begin with, before it was stored. Or can exposure to light through the plastic do it?<br /><br />I put on almost another 100 hours this season and she ran fine, so I had no reason to do anything more than routine checks. I did not look at the plugs I had installed at 200 hours.<br /><br />Yesterday I did the routine maintenance and storage programs. All four plugs were pretty oil-fouled. Not enough to have run bad because she didn't--- but crummy-looking. It's possible that they were not tight enough since there was a little oily residue along the threads. They feel plenty tight at more like 3/16ths than at the recommended 1/4 turn. This year I torqued to 20, but it looked about the same as last year as far as the 1/4 turn goes.<br /><br />I'm worried that the gummy gas screwed up my nice engine's rings or valve guides or stem seals and she just didn't complain about it yet. <br /><br />I brought the boat back home this year and will be taking it in to a different local Merc dealer later this winter to do another a 100 hour check. I kept the old plugs. If I tell them the whole truth I could chalk up some expensive hours to just check, not to mention possible repairs. The other things I could do is play even dumber than I am and just show them the plugs, or I could quit worrying and just go with it unless she starts to run bad. But that could screw up fishing for the Summer of '06.... <br /><br />What wuld you guys do?
