Small Engines (Lawn Mowers, etc.): engine problem, flow problem, lawn mower

Question
I have a lawn mower 4cyc engine (BRUTE), and if i cover the air inlet partially (carburator), it starts, but otherwise starts and stops. I checked the spark plug and it looks OK.

any sugestions?

many thanks

Answer
Hi Olga,

It sounds like a choke or fuel flow problem.  If there is a fuel primer bulb, it may be torn or leaking.  If there is a choke it may need adjusting.  Try adjusting the carb mixture screws but note how many turns out, they are now, so you can return them as is if that doesn't help.  Finally the carb may have dirt, debris or gummed fuel inside it.  In that case the carb would need to be removed, disassembled and cleaned.  

Let me know how you make out.
Michael