Small Engines (Lawn Mowers, etc.): Briggs engine hard to start, twin cylinder engines, ohv engines

Question
John,
I have a 20hp briggs on a Yard Man riding mower. Starting the end of last summer and all of this summer I have had trouble starting the engine. When it tries to crank it is very sluggish as if it were in a bind. I tried replacing the battery, but that didn't help. I have changed the fuel filter and spark plugs, still no luck. The engine runs fine if I can ever get it to crank. What do you think it could be?

Answer
Hello Jeff:

This is a Common Problem for the OHV Engines. The Valve Clearance Needs to be Reset. This is the Clearance Between the Valve Stem Top and the Rocker Arm. 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 (Both Rocker Arms will have Play in them when the Engine is at TDC) When Setting the Valve Clearance. Now Loosen the Valve Adjuster Locks and Set the Intake Valve Clearance to .004in -.006in and the Exhaust to .008in - .010in. I have had Better Performance Out of the Mowers and Less Burnt Valves Using these Settings. Hope this Helps. I am Here if You Require More Assistance. Let me Know What Happens, Please. 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 9pm EST (US). My New Day Starts then. Thanks.

Respectfully

John