Small Engines (Lawn Mowers, etc.): B&S 12 HP engine, switch jumper, jumper wire

Question
I had a family of mice move into my engine. I didn't know this until after my tractor stalled. I cleaned everything up and it seems like there is still compression but it will not start. Just how trashed is this engine?

Answer
Hello Mike:

LOL. I Just Hate that. It Happens to me All the Time. I have Equipment that Sets for Long Periods of Time, without Use. Everyone Forgets to Check the Equipment before they Leave with it. LOL  You Know what Happens. It was Started and Ran Good at the Shop. Now it has Quit and Will Not Start. The Best Thing is to do is Forget About the Mice. Lets Do a Diagnostic Check and Locate the Actual Cause of the Problem. 1- Is the Plug Firing? If No, then Disconnect the Shut Off Wire from the Coil/Ign Module/Magnetron. If the Plug Fires, then Check the Safety Switches. PLEASE REMEMBER THAT THE INSTRUCTIONS FOR CHECKING THE SAFETY SWITCHES IS JUST THAT!!! FOR CHECKING ONLY. I NEVER Suggest a Mower be Operated with a Safety Device or Switch Disconnected or Bypassed. Now. On Some Model Mowers you can Simply Unplug the Safety Switch from the Harness. On Other Models you have to Place a Jumper Wire Between the Harness Terminals (on the 4 Post Switch Jumper from Same Color Wire to Same Color Wire). Check the Clutch/Break and the Blade/PTO Safety Switches First. Check the Seat Safety Last. Usually the Seat Safety is Not in the System for Starting the Engine. Just to Ensure Someone is in the Seat when Engaging the Transaxle and/or Blades. If the Safety Switch Check is Good, then the Mice ARE the Cause of the Problem. The Most Likely Chewed a Wire Bare and it has Grounded the Shut Off Wire or the Ign Switch is Bad. If the Plug is Firing, then Pour a Small Amount of Gas (1oz) Into the Carburetor Throat. If the Engine Starts and Quits or Even Just Fires a Few Times, then  Remove, Disassemble and Soak the Carburetor Overnight in Carburetor Cleaner (I Use Gunk). I have Found that Most People can Use a Breakdown/IPL and Disassemble the Carburetor Enough for Proper Cleaning. You Only have to Remove the Bowl, Float Pin, Float (if Applicable)  and Needle Valve and Any Adjustment Screws that Go Into the Carburetor Body. The Welch Plugs Do Not have to be Removed. Then Soak the Carburetor Body and Parts in a 1 Gallon Can of Gunk Carburetor Cleaner Overnight. The Can has a Parts Tray Inside it for the Small Parts. Once the Carburetor and Parts are in the Cleaner, you can Replace the Lid for Safety and to Prevent Accidental Spillage. Then Blow Out the Passages with Compressed Air. Install New Parts if Required. I Sent these Instructions to Get you Started. Send me the Model Numbers Off the Mower, Please. With these I can Locate the Proper Manual and Better Assist you. Send me the Model and Type or Spec Numbers Off the Engine, Please. With these I can Locate the Proper Manual and Better Assist you. 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. Have a Happy Holiday Season and May the All Mighty Bless You and Yours. Be Safe and Happy. 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. Thanks.

Respectfully

John