50NG firing on and off while starting
Sorry about the "Subject" line but it's hard to describe this in one line. What's happening is my ZDZ 50 NG was starting awesome all spring and summer. Then the last two times out when I start it, it starts, picks up RPMs and then almost dies, then picks up RPM's again and almost dies....etc etc etc. It sounds like someone is operating the throttle really quick from half to idle, back and forth. But I am keeping the throttle stick in one place. It does this about 2 times a second until it finally dies. The only thing that finally gets me past it is several re-starts and goosing the throttle until I finally bust into the high end RPMs....then it runs awesome. Is this simply a fouled plug? My buddies say it sounds like the ignition is acting up, misfiring...but it does finally start and runs awesome. It seems to be most prevalent at the first start of the day. The only change I made was going from Pennsoil air cooled 32:1 to Mobil 1 Racing 2T synthetic 32:1. I re-tuned the needles with the Mobil 1 and it ran awesome for about a gallon.