Small Engines (Lawn Mowers, etc.): sears lawn mower wont go into gear, drive pulley, mower deck

Question
Hi there,

We have a 1999 sears 21.5 horse power with a 42" cut.  Last year I had to replace the mower deck.  But yesterday I started the mower up and it started right up and when I engaged the clutch I could not back up.   then I put it in drive and could not drive.   I tried the mower and it worked fine.  The only thing I did was I had to take off the back tire to fix it the tire.  I took off the back plate where the hich is to look at the belt but I never looked at the belt up near the motor.  Do you think its a belt problem?   This has never happend before.  The mower deck belt has gone 2 times but the main belt has never been replaced.  

Thank you
DJ

Answer
The belts would be my first area of concern the main drive belt could be worn and slipping or may have come off the drive pulley alltogether maybe oil or lube has dripped or leaked onto the belts or friction wheels . If the belts are fine than move to inspecting the linkage that controlls the engagement of the transmission, and or the transmission assembly itself. I'm sorry I dont work on riders so I dont know much about their internal workings. Start at the drive pulley and work your way through the drive sytem. Be patient and use logical reasoning when going through the steps of how power gets from the drive pulley on the engine to the wheels. and allways remove the sparkplug wire when working under the deck. I wish I could be of more help. You may want to reffer to one of the other gentlemen on this site.