Small Engines (Lawn Mowers, etc.): Techumseh 6hp pull chord stuck, starter clutch, compression stroke

Question
John, I've had a number of issues with my Tecumseh 6hp.  The latest is that I cannot crank the pull chord.  I was previously having problems starting the motor, but finally got it going.  I added some fuel line cleaner, which emitted a large amount of smoke.  I believe I also added too much oil.  I have drained the excess oil from both the tank and the spark plug cylinder.  
Now my problem is that I cannot unwind the pull chord when it is bolted in.  I have removed the mechanism and the pull chord unwinds fine when removed.  I can separately turn the bolt and rotate the blade.  What might be the problem and what do I do to correct this?  
I'm not sure if there is a problem with the flywheel key.  A few months back the blade hit a small tree stump which may have caused a problem which is only now evident.  Your thoughts are greatly appreciated.  

Answer
 Hello BC:

 1- The Rope Problem sounds like the Starter Clutch are Rusted and Requires Lube. 2- The Hard to Start May be the Flywheel Key is Damaged Due to the Stump Accident and has the Spark Plug Timing Firing Slightly Out of Time with the Position of the Piston on the Compression Stroke. Replace the Flywheel Key. Send me the Model Numbers Off of the Engine, Please. With these Numbers I can Locate a Breakdown of the Engine and can Better Assist you. Hope this Helps. I am here to Help if you Require more Assistance. Let me know what Happens, Please. I enjoy knowing the Outcome. Thanks.

 Good Luck

 Respectfully

 John