Surging Issues

[Greg Mallek]

Im happy to say that my "Surging" issue has been defeated. I changed both fuel filter, and water seperator, added some "Heat" to the fuel, new cap and rotor, and then a new batch of plugs. I finally was able to get out yesterday, and she ran better that I can remember ever running. I guess theres something to be said about leaving the basic maintainance to others. "Oh ya dad, we did that". Haha. Im taking over again !! Thanks for all the input, and thank goodness I didnt have to get into the fuel pump$.

[IDBoating]

I fixed a buddy's Mercury V6 earlier this year. Had several issues but after everything "measured" correctly it still wouldn't run properly. I had pulled and checked the plugs, regapped, and reinstalled, and all looked fine internally. But then I noticed the hexes on the plugs were a little corroded. I asked when he had last replaced them. "Couple of years ago." I bought six new plugs, gapped and installed them, and BAM - engine worked perfectly. Been running all summer since.

I saw a reference somewhere long ago that the ECU on that engine actually uses the plugs as part of its sensor system. I can't imagine how - there's tens of thousands of volts on them, and the CDI's don't appear to have a return signal path. But I pulled six "good looking" plugs, replaced them with six new plugs, did nothing else, and all sorts of problems just went away. Something to keep in mind.

[boatwakes]

Awesome!!! Glad to hear it was just the basics and you're back on the water again.