Small Engines (Lawn Mowers, etc.): Tecumseh Engine Starting Problem, blown head gasket, proper manuals

Question
I have a Murray mower with a 5 hp Tecumseh and after it starts it runs with a slight miss sound and lacks power.  If I remove the air filter it runs good.  As soon as the air filter is put back in it starts to run poorly again and if I tighten the filter cover it almost quits, but still continues to run very poorly.  I have replaced the filter and spark plug.  It's like it is getting too much gas.

Answer
Hello Jake:

Depending on the Model, it May be the Valves Require Adjustment. The Intake Gasket is Drawing Air. The Carburetor Air Mixture Screws need Minor Adjustment. A Blown Head gasket will Cause this Also. Send me the Model Numbers Off the Engine, Please. With these I can Locate the Proper Manuals and Better Assist you. Hope this Helps. I am here if you Require more Assistance. Let me know what Happens, Please. Thanks.

Good Luck

Respectfully

John