My HT 66cc motor with about 3 gallons of fuel through it runs really rough when I try to set the plug gap to .025 or bigger.
It misses really bad and eventually raw fuel fouls out the plug after trying to run it for a minute.
The other day I was trying to fine tune it and when the motor was warm I was able to run it at .035 gap on 1st try and motor ran a lot smoother then the previous .022 gap so I put it away and today it did this on cold start. I put the gap back to .022 and all is fine. I tried other gaps in between and maximum it will run without misfiring seems to be about .022
anyone know if this is a symptom of impending coil or cdi failure? I've seen other post people running .035 gaps without problems.
BTW motor is all stock basic 66cc china with NT carb and I am NOT using the white wire for anything. I also tried other plugs and a different wire with the same results.
Also when I pulled the mag cover I noticed a little black fluffy looking material inside there. It almost looked like black carbon cylinder deposits but it didn't have the smell or consistency of carbon when I touched/smelled it.
It misses really bad and eventually raw fuel fouls out the plug after trying to run it for a minute.
The other day I was trying to fine tune it and when the motor was warm I was able to run it at .035 gap on 1st try and motor ran a lot smoother then the previous .022 gap so I put it away and today it did this on cold start. I put the gap back to .022 and all is fine. I tried other gaps in between and maximum it will run without misfiring seems to be about .022
anyone know if this is a symptom of impending coil or cdi failure? I've seen other post people running .035 gaps without problems.
BTW motor is all stock basic 66cc china with NT carb and I am NOT using the white wire for anything. I also tried other plugs and a different wire with the same results.
Also when I pulled the mag cover I noticed a little black fluffy looking material inside there. It almost looked like black carbon cylinder deposits but it didn't have the smell or consistency of carbon when I touched/smelled it.
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