This engine is fitted to a horizontal mower.
After 20 mins running it falters for 30 seconds and then stops and will not restart. After 20 mins starts again OK. It runs at normal speed, air cleaner is clean, clean fuel. The plug is really white which I would say makes an engine run hot ? If so - how do you make the fuel a little richer ?
Any ideas from other users.
Regards,
Mike

Mike C., April 2009

You're right Mike, your engine is running too lean - the plug colour should be brown. Is this the engine with the petrol tank below the carburettor? There is a mixture adjustment screw alongside the primer button if I remember correctly, and with the engine running fast, turn this screw out until the engine falters or blows black smoke - and then turn it back in again until the engine starts to run smoothly. Its also a good idea to replace the diaphragm between the carb and the tank if it has been disturbed.

John, April 2009