Ok, I've already went pretty far into this thing, but this is how it goes:
For the past 2 seasons, I've had a bit of a high rpm misfire issue (usually around 7,000 rpm) after the sled warms up, I've been chasing this problem since then and never found an issue.
This season, I took the sled out of storage and it was running terrible, wouldnt idle and lacked power until about 3,000 rpm - then it would run great.....So, I took the carb off, cleaned the jets and found 1 plugged pilot jet, cleared that out. While I was at this point I figured I would pull the wiring harness out from under the engine to check for rub through (the portion that runs up to the gauges on the hood). I pulled it out (was a huge PITA to get it out), and found that while most of the plastic/rubber coating was worn, there was no rub through on the actual wiring insulation. I rewrapped everything and rerouted it around the engine. I then got the sled together and it was still having trouble idling...I raised the idle a bit, and it seemed perfect. Had throttle response and kept itself running well on the trailer.
That brings me to today. I took the sled out, started going through a field and it felt like it was lacking power (like running a cylinder down), a few seconds later it had barely enough power to pull its self. While it was running, I was able to pull both the pto and center plug caps off and nothing changed, but when I would pull the mag off, it would die immediately. It's only running on the mag cylinder.
I already ohm'd out the stator, the plug with 2 wires had ~210 between then, and each of the wires on the 3 wire plug had about .5ohms between then, I believe this is in spec. I also swapped the coils around, and nothing changed, still only running on the mag cyl. While I had the coils off I sanded down the bolt connections and tighened up the electrical connections; this did not help.
I do not know what to do next. Likely a cdi issue? Is there any way of checking the CDI? Possible wiring issue that resulted from pulling the harness out from under the engine?
For the past 2 seasons, I've had a bit of a high rpm misfire issue (usually around 7,000 rpm) after the sled warms up, I've been chasing this problem since then and never found an issue.
This season, I took the sled out of storage and it was running terrible, wouldnt idle and lacked power until about 3,000 rpm - then it would run great.....So, I took the carb off, cleaned the jets and found 1 plugged pilot jet, cleared that out. While I was at this point I figured I would pull the wiring harness out from under the engine to check for rub through (the portion that runs up to the gauges on the hood). I pulled it out (was a huge PITA to get it out), and found that while most of the plastic/rubber coating was worn, there was no rub through on the actual wiring insulation. I rewrapped everything and rerouted it around the engine. I then got the sled together and it was still having trouble idling...I raised the idle a bit, and it seemed perfect. Had throttle response and kept itself running well on the trailer.
That brings me to today. I took the sled out, started going through a field and it felt like it was lacking power (like running a cylinder down), a few seconds later it had barely enough power to pull its self. While it was running, I was able to pull both the pto and center plug caps off and nothing changed, but when I would pull the mag off, it would die immediately. It's only running on the mag cylinder.
I already ohm'd out the stator, the plug with 2 wires had ~210 between then, and each of the wires on the 3 wire plug had about .5ohms between then, I believe this is in spec. I also swapped the coils around, and nothing changed, still only running on the mag cyl. While I had the coils off I sanded down the bolt connections and tighened up the electrical connections; this did not help.
I do not know what to do next. Likely a cdi issue? Is there any way of checking the CDI? Possible wiring issue that resulted from pulling the harness out from under the engine?
