Small Engines (Lawn Mowers, etc.): Toro Mower does not run with power, assembly drawings, mower blade

Question
The mower was unused for 2 years, properly stored, and when I attempted to start
the engine, it would not start.  I disassembled the carb and cleaned it, running carb
cleaner though all the passages I could find, removed and cleaned the jets, etc...  At
this point the engine started, but ran roughly.  I got it adjusted to a point where it
would run with the choke fully open , but it had little or no power, engaging the mower
blade cause it to stall.  By closing the choke about half way the engine runs with good
power, engages the blade, etc...  but is it not right...  I assume the engine is running
lean.  I disassembled and soaked the carb in carb cleaner, with no cahnge.  I am not sure where to go from here.  Any help would be appreciated.  

I believe
this is a Toro model 20526C.

Thanks,

Arnie


Answer
Hello Arnie:

You can View a Breakdown/IPL of the Mower at this Site Addy, https://lookup3.toro.com/partdex/default.cfm and Select Start Parts Viewer. Now Enter the Model Numbers (20526C) and Click Search. Now Select View Assembly Drawings. Select the Carburetor File. Even though you have Soaked and Cleaned the Carburetor, then Main Jet May Not be Cleaned. I have had to Soak and Clean Carburetors 2 or 3 Times to get the Main Jets Fully Clean. If the Carburetor is Still Cause this Problem After the 3rd Cleaning, then I Replace the Carburetor. The Problem is the Small Port in the Main Jet is Still Slightly Restricted and Not Allowing the Engine to Get the Proper Gas Mixture. Use a Small Wire and Clean the Small Port in Nozzle (#20 in the Carburetor Breakdown at the Site Addy I Provided) and then Soak the Carburetor a Second Time. I Suggest you Check the Compression Also, it May be the the Valve Clearance Requires Adjusting. 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 Locks and Set the Intake Valve Clearance to .004in -.006in and the Exhaust to .007in - .009in. 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.** 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 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. Thanks.

Respectfully

John