Small Engines (Lawn Mowers, etc.): Briggs 686cc twin engine., twin cylinder engines, blade style

Question
Hi John,
This engine will not turn over either with its own battery or a jump from a landrover battery!If if I remove one plug it starts up great.I have read that it my be the valve settings are incorrect is it a huge job to adjust these valves and how do I get to them what is the basic prcess does both heads have to be removed?

Thanks Andy.

Answer
Hello Andy:

Send me the Model Numbers Off the Engine, Please. With these I can Locate the Proper Manual and Better Assist you. If you are Sure the Starter is Not Binding Under a Load, and If this is an OHV Engine, then the Valves Are Easy to Reset. The Only Special Tool Required is a Blade Style Feeler Gauge. 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 .003in -.005in and the Exhaust to .008in - .010in. I have had Better Performance Out of the Mowers and Less Burnt Valves Using these Settings. From your Description, it Sounds like the Valves need to be Reset so the Compression Release will Operate Properly. 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