86 Force 125 dropped cylinder

[Tupper]

Within the last year I installed a water pressure gauge, replaced both CDI boxes (rewired to Mercury), the trigger, stater, replaced the gas tank, and rebuilt the carb. Ran fine this year, but 4 week in I was coming back to dock and lost all sorts of power, dropped to 3000 rpm, and limped home (felt like running on 3 cylinders). Checked plugs, fine, second hole down was hotter than the other three (I think this is the one I dropped). Head was warm, but not hot, water pumping fine. I did a compression check and all 4 cylinders compared equally (did it cold though, as I did not want to idle that long). I have read a lot about carbon, which I have not run anything through to de-carb it. Could this be a blocked exhaust port? Could the single hot cylinder be electrical? Need help

 

[12Footer]

Re: 86 Force 125 dropped cylinder

it could be fuel or electrical. test the ignition. If ok, test it on the water.When it drops RPM,squeeze the primer and see if it picks back up.

 

[Tupper]

Re: 86 Force 125 dropped cylinder

Thanks for getting back so fast. I like your other aswers in this forum. One problem is that when I take the throttle from neurtal back to 12 o'clock it stalls for sure. Should I start it in gear and take off from the dock, or tow it in and check the ignition?

 

[Deerdog]

Re: 86 Force 125 dropped cylinder

Tupper,<br />I aint no boat engine expert but have learned alot from the guys here. Anyway, what you are describing sound very much like my Force 150 (same as yours but one extra cylinder). It lost power (bogged) and then began missing at 3000 to 3500, caught back up and started the cycle all over again. Plugs were fine, fuel was fine, and it would idle like a kitten. I suspected either a coil breaking down or a stator or trigger.<br /><br />Took it to the shop (run by a friend of ours) and it turned out to be a stator wire breaking down (actually it was broken inside but not totally, if that makes sense)<br /><br />Replaced the wire and the thing runs like a streak. 50 mph plus at 5500 RPM - which is good considering the boat is heavy (19889 Arriva).<br /><br />Hope this helps. when it happened to me the first thing I suspected was a cylinder until we looked at the plugs. Was somwhat relieved.<br /><br />Deerdog <br />Took it to