i have a izy starts with petrol down the plug hole replace plug she fires sttraight away then dies.there is a spark at the plug when held at the engine case .cleaned carb spotless.do we think the plug is breaking down .
my right arm is hanging off and the kids are scared to come into the garden when dad trys to cut the lawn .many thxs

Des, September 2011

Replace the plug.

The non-resistor version, BP6ES will be fine. I also had a spark with old plug (BPR6ES, which contains a resistor to prevent radio interfrence!) but fuel change and plug clean had no effect.

As soon as I replaced the plug it ran; with plenty of black smoke for a few mins but now runs OK on all throttle positions including idle. Something it never did before.

Tom Wilson, September 2011

What makes you assume the carb is spotless- just by looking inside maybe? False policy- it's the particles and varnish you can't see that causes problems like this. Remove the carb and take it to your local repairer and request they ultrasonically clean it out and then re-fit. Either that, or simply replace the carb with new- they are only around £40, so no money.

pleasant, September 2011