Small Engines (Lawn Mowers, etc.): Tecumseh snow king OHV 11.5 hp, twin cylinder engines, compression stroke

Question
The last time i used my snow blower it ran fine, went to use the other day and would not start, kicked back so hard it ripped the handle out of my hand and the pull start handle broke. Tried the electric start and still no luck. Also seemed to be popping back through the carb, so far have checked to see if valves are moving, piston moving, pulled flywheel to check keyway, pulled head to check valve and piston condition. All seem ok,is it possible that the cam has jumped time? Not sure if there is some plastic gear that might have jumped a tooth? only 2 years old and used about 20 hours. never had a problem starting before. Thanks for any help. Kevin model#OH318SA  

Answer
Hello Kevin:

Did you Check the Valve Clearances when you Check the Valve Movement? If No, then the Valve Clearances Require Setting. This is a Common Problem with the OHV Engines. The Following is a Basic File I made for Setting the Valve Clearances. Any Input is Appreciated. **I Do Not Use the Setting Called for by the OEMs. I have Found that the Following Works Best. Remove the Valve Cover (on the Dead Cylinder for Twin Cylinder Engines). Set the Cylinder you are Setting the Valves on to Top Dead Center on the Compression Stroke When Setting the Valve Clearance. Now Loosen the Valve Adjuster Lock and  Using a Blade Style Feeler Gauge, Set the Intake Valve Clearance to .004in -.006in and the Exhaust to .004in - .006in. Loosen and Tighten the Rocker Arm and the Feeler Gauge is Placed Between the Rocker Arm and the Valve Top where the Rocker Arm Pushes on the Valve. ***BE SURE TO TIGHTEN THE ADJUSTER LOCK AFTER YOU HAVE THE PROPER VALVE CLEARANCE*** I have had Better Performance Out of the Mowers and Less Burnt Valves Using these Settings. Be Sure the Piston is at TDC on the Compression Stroke.** If you Remove the Valve Cover and then Turn the Engine by Hand, you can Watch the Intake Valve Movement. When the Intake Valve Closes, the Piston will Just Starting the Compression/Power Stroke. On Some Engines you can Us a Straightened Coat Hanger and Feel the Piston. Be Careful and Dont Jam the Wire in the Cylinder. Usually the Piston will Push the Wire Out of the Spark Plug Hole with No Problems. If the Valve Clearance are Correct, then the Cam May be the Problem or Depending on the Model of the Engine, the Compression Release May Require Replacing. The Compression Release is Either a Part of the Cam or is Attached to the Cam. I Used the OH318SA-221803B Model Engine for a Reference.
Please, Do Not Hesitate, 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

PS: I am Allowed to Answer 10 Questions a Day. If you See I am Maxxed Out, then Try Submitting your Question at or Just After 8pm EST (US). My New Day Starts then. Comments and Ratings are Greatly Appreciated. Thanks.

Respectfully

John