Small Engines (Lawn Mowers, etc.): Lawnmower running problem, fuel flow, minuets

Question
Hi,
I have a Mountfield Emprass lawnmower which starts OK but after a few minuets stops and i have to wait a short while and start it again and the same thing happens again.
Hope you can help.
Nick  

Answer
Hi Nick,

Sorry for my delay, due to the holiday

You will need to determine if the problem is a lack of spark or a lack of fuel flow.  Right after it quits, remove the spark plug, reconnect the wire and lay it against the engine head.  Pull the engine over and watch for spark at the plug's electrode.

If good, then try to start it while squirting fuel or starting fluid into the carb intake.  If it starts and you can keep it running by adding fuel, then the carb most likely has dirt, debris or gummed fuel inside.
You will need to remove the carb, disassemble it, clean all the small internal openings and blow it out with compressed air.   Probe each and every hole with a small wire.   A carb rebuild kit wouldn't hurt either.  

Another possibility if the problem is fuel related: Check the gas cap to make sure it is venting and not causing a vacuum in the tank.  

Let me know how you make out.
Michael