Small Engines (Lawn Mowers, etc.): 17.5 0hv B/S, twin cylinder engines, adjustment screws

Question
QUESTION: i have plenty of bright blue spark (new starter and realy it cranks fine) took off carb and cleaned throug out (bowl flowts  extra) and it still wont fire up?????stumped(but it ran prier to after the starte and relay went....any suggestons thankx jim

ANSWER: Hello Jim:

Will the Engine Start and Quit if you Spray Starter Fluid Into the Carburetor Throat. If Yes, then  Remove the Carburetor Solenoid and Go to the Hardware Store. Purchase a Bolt of the Same Diameter and Threads. It Needs to be 3/4" Long. Put this Bolt in Place of the Solenoid. If this Corrects the Engine Problem, then Replace the Solenoid. ***NOTE: THIS IS FOR CHECKING THE SOLENOID ONLY I NEVER SUGGEST YOU OPERATE THE ENGINE WITH THE SOLENOID OUT OF THE CARBURETOR EXCEPT FOR TESTING PURPOSES*** Sometimes the Plunger is Moving, Just Not Far Enough to Allow the Gas to Enter the Jets. If the Carburetor Solenoid is Good, 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 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. If the Engine will Not Start Using Starter Fluid, then Remove the Valve Cover and Check the Valve Clearance. The OEM Says to Set them Both at .004in. 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. If the engine Still Does Not Start, then Check the Compression. 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 you Question at or Just After 9pm EST (US). My New Day Starts then. Thanks.

Respectfully

John

Hello Jim:

Thanks for the Good Words and Ratings. I Wish you would have Gotten Back to me. If the Diagnostics Above have been Performed and the Engine Still will Not Run, then Check the Flywheel Key. If the Flywheel Key is Damaged, the Plug will Fire Out of Time During the Compression Stroke and the Engine will Not Run Even with Gas and Compression. Also, it Will Not Backfire All the Time when this Happens. Hope this Helps. I am Here if You Require More Assistance. Let me Know What Happens, Please. Thanks.

Good Luck

Respectfully

John

---------- FOLLOW-UP ----------

QUESTION: helheel lo john its jim just asking you another stupid question it seems like to much compression if i take out the plug it cranks fine put it back it wont crank with out hesitation checked the key on the flywheel it looks ok but the previous customer tried pullin the wheel(had to retap the thread to get the bolt to fit)so were to we go from here thanks your truly jim  jimbosscooters2@yahoo

Answer
Hello Jim:

You Reset the Valves to Intake .004in and the Exhaut to .009in. The Flywhel Key is Good, then Check the Engine Oil. Is it Overfilled and Smell like Gas? If the Oil is Good, then the Counter Balance Weight Inside the Egine May have Sheared its Bolt and is Not Operating Correctly. Hope this Helps. I am Here if You Require More Assistance. Let me Know What Happens, Please. Thanks.

Good Luck

Respectfully

John