Its worked fine for 10 years then it started "hunting" and slowing down then eventually stopped. I have replaced the plug based on several previous suggestions and it ran on full throttle for 30 secs then packed in. The plug was black when I removed it along with the air filter that was completed flooded with petrol. Ordered a service kit and will give it a go at the weekend. Any other suggestions?
Wouldn't have wasted money on a kit and neither would i waste more money on getting the carb ultrasonically cleaned either. By the time you've spent all that money with no guarantee of success you could have simply unbolted and replaced the old carb with new for little more than £30. Carbs for these are so cheap now it's not worth mucking about- especially as you've probably spent nothing on maintenance on it in the 10 years you've had it.
try and get the carb ultrasonic cleaned and when refitted make sure the choke is being fully engaged
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