Engine problems

[derek81]

I have an 18ft stratos with a Johnson 150 faststrike (92 model) and when i was circling the boat around yesterday to load onto the trailer about half way to the trailer it started idling real crazy, it was shaking the boat and was really hard to pull out of gear to stop it in time when i hit trailer. Best way i can describe it is that it sounded like you were pushing the gas on and off over and over again really fast, instead of idling normal to the trailer it picked up speed and was shaking the motor pretty violently. Once it was back in neutral it seemed fine, i turned the engine off and restarted it and as soon as i put it in gear it did the same thing. I plan on having it looked at later in the week but thought i'd see if any of you engine guru's had any suggestions in the meantime.

 

[wrechin2]

Just dealt with a similar issue this weekend. Was a bad power pack. Have one that acts crazy coughing when cold and runs normal when hot. I have 2 test packs and The first one I put on done almost that. The other test pack did not and he called me this AM and said it was running good with my pack on there. So I have a bad test part as his boat wasn't doing that before I swapped the packs out. </p>

That power pack is split into 2 boxes built into one. On the right side of the engine is a shift interrupt switch. It causes the engine to misfire on cylinder 1-3-5 to allow the lower to shift out of gear easily. If the shifter has to be forced it toggles this switch and causes it to misfire. Could be a bad switch or bad pack. To test the switch, remove the plastic "square" cover on top with 4 screws in it. There will be a set of wires coming off the right side (drivers side) of the engine that are black with yellow tracer. There you will find a connector. Unplug the connector and see if it continues to "surge". If it does not "surge" unplugged, then it is a bad switch or misaligned.</p>

<font color="#ff0000"><font size="6">With the switch unplugged it will have a high shift effort!! Turn engine off to get out of forward or reverse!!!!!!</font></font>
</p>

Sound similar to "quick start" feature but can not be triggered by shifting. </p>

Of course this is from you description emoToast</p>

 

[derek81]

Thanks wrenchin, i turned it off the second time, it happened right as i was trying to line the boat with the trailer and it jolted forward, happened to fast to think about what to do, first reaction was to try and throw it in neutral which actually threw it in reverse, i'm sure the guy next to me thought i was an idiot......thanks again!

 

[wrechin2]

No problem. Hope it is simple!!