Small Engines (Lawn Mowers, etc.): tecumseh 143.986000, vent hole, fuel cap

Question
This engine sets on a acraftsman deck, model # 917.387301.
I have already replaced the carb.  I have replaced the hoses and cleaned the intake chamber.  The oil is new along with the gas.  I can get it running, but when it starts to idle down, I have to press the primer bulb to get it back to speed.  It will run after getting hot.  If I have to shut it down for any reason while mowing, I have to press the primer bulb to restart.

Answer
Check to see if your getting a good fuel supply to the Carb. from the tank. Remove the line, is a good flow present from the tank? Another common problem is the vent on the cap clogged, this needs to be open to maintain a good flow it is gravity feed, a clogged fuel cap vent hole with cause a fuel lock, get it running and remove the cap, wait a few seconds, if it helps either replace the cap or unclog the vent hole. Is the tank clean ? Sounds to me to still be a fuel problem. But I would check the plug for correct gap, and making sure it's clean. Is the flywheel key partially sheared? ......Tom