Small Engines (Lawn Mowers, etc.): One of the cylinders aren;t functioning correctly. why?, craftsman lt1000, briggs and stratton

Question
On the left side of my B&S 20hp v-twin engine, there are pistons that are supposed to be moving, yet for some reason they are not. The pistons on the other side of the engine are working correctly and moving and i don't understand why one side does and the other side doesn't. I really have not a clue what it could be. I also took the part of the cylinder assembly apart, but it did me no good as I didn't see anything that didn't look out of the ordinary to me. If it helps, my tractor is a Craftsman LT1000 20hp OHV V-Twin. Also, I the model number for it is 407677..the type  is 0229E1.. and the code is 020812YG.. I don't know much of any other way of explaining it, I am not too literate with small engines, especially Briggs and Stratton engines. Please help me! If you have any questions at all that might help you if I can get you an answer to them, please feel free to email me at: xmadcrzyx@gmail.com

Answer
Hello Brian:

From your Description it Sounds like you are Talking About the Valves Not Moving. If you have the Large Piston in the Cylinder Moving and the Smaller Valves to the Side of the Cylinder are Not Moving, then you May have a Cam or Tappet Problem. You can View a Breakdown/IPL of the Unit at this Site Addy; http://www.briggsandstratton.com/maint_repair/manual_and_more/doclist.aspx?categ... and Enter the Model Numbers (XXXXXX) and Type Numbers (XXXX) in the Appropriate Boxes and Click GO. Then Select Download PDF. In the PDF File of the Engine at the Above Site Addy, the Piston is on Page 2 of 11 and is #25 in the Breakdown. The Valves are Shown on Page 3 of 11 and are #s 33 and 34 in the Breakdown. Are the Push Tubes that Move the Rocker Arms Bent? If Yes, then you May have a Stuck/Sticking Valve and it is Causing the Push Tubes to Bend. If the Large Piston is Not Moving, then the Connecting Rod has Broken and will Require Replacing. If you Hit a Snag or this Does Not Correct the Problem,  I am Here if You Require More Assistance. Hope this Helps. Let me Know What Happens, Please. May the All Mighty Bless You and Yours. Thanks.

Good Luck

Respectfully

John

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Respectfully

John