Small Engines (Lawn Mowers, etc.): Engine Short, internal passages, diameter wire

Question
I was recently given a used lawn mower and have had no problem with it until now.  When I pull the cord to start the mower, it runs for about 3 seconds and stops.  The only way to get it to start is hit the fuel pump a couple of times.  I have cleaned to spark plug and cap, but that did not help, and aside from all of this the oil is leaking out of a plastic tube on the side of the motor.  I recently filled up the oil and I'm not sure if I put toom much in or I have another problem.  

Answer
It sounds like you have two problems.  First, make sure the oil level is correct with the mower sitting on level ground.  Your second problem indicates the carburetor is plugged.  If it only runs on choke or after being primed, this indicates a no fuel condition.  You would need to remove and clean the carb thoroughly, including pushing a small diameter wire through all of the internal passages.  Then follow up with aerosol carb cleaner.  Hope this helps.