Hi, there are many reasons why an engine will run and stop...carburettor cleaned, have you cleaned the petrol tank out? there may be loads of bits floating about ready to block the tanks filter, doesn't seem likely to me but try the cheapest options first, more expensive is a sticking valve, or maybe the ignition coil is faulty... check for a spark after the mower has stopped when it's hot, get a new spark plug before assuming the worst. If there is no spark and you have fitted a new plug the coil becomes suspect, I used to check coils using a meter but I don't think a digital meter would be any use.
Bernay
March 2010
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