Small Engines (Lawn Mowers, etc.): briggs & stratton engine 42a707, briggs stratton engine, briggs stratton

Question
HI,I have a rider with this engine42a707--2653EI---9910115A .It starts and seeems to run ok but it feels down on power.The engine bogs down under much less load than it used to.I am pretty handy but small engines are new to me.It is 10 years old(2000)and I have only ever done the basics like plugs,filter oil etc.Is there something I'm missing that should be done as maint.The fuel filter is a couple years old.When I first start it and push the throttle it acts like it isn't warmed up but then it straightens out in a few minutes,choking does'nt seem to help this.there is some drag when I turn the blades by hand but not too bad.sometimes I can hear a squeeking sound but can't tell where it is coming from.What do you think and thanks

Answer
If you have a loss of power it could be any of a number of things. First  of all I would look at the carburetor, the gasoline we use these days is not very forgiving to small engines. If it is clean and the jets are all clear you could have a leaking head gasket. That is the only thing I can think of in regards to the squeaking sound you are referring to. From there it could be a valve issue or something I haven't even considered. If you do clean the carburetor, go ahead and change that fuel filter, it's a small price to pay to guarantee no dirt will get in the clean carburetor.