Small Engines (Lawn Mowers, etc.): Tecumseh 4 cycle engine, plastic nozzle, float bowl

Question
Hi,
I have a 4 cycle Tecumseh engine on a Lawnboy SP mower. When cold, I use the primer bulb on the side of the carburator, but the engine won't start. If I remove the air filter and pour in a liitle gas it will start and run perfectly. I have cleaned the carb and it doesn't help. Could it be the valves? The mower really hasn't been used much as I only use it for trimming. Any ideas?
Thanks, Tony

Answer
Well Tony it sounds to me like your o-rings are bad in the carb. That's why it won't prime. You need to remove the carb and air filter base. Next remove the float bowl and float. After that look into the carb, you'll notice a plastic nozzle. With a screwdriver gently push the nozzle down. Flip the carb over and with a pick remove the tube. It's wear the screw for the bowl goes. Replace the 2 o-rings on the tube and reassemble. Make sure you get the second o-ring out, it sticks up in the stem sometimes.   GOOD LUCK