Small Engines (Lawn Mowers, etc.): high speed snow thrower, friction wheel, rubber wheel

Question
I got a 5hp crafstman 2 stage snow thrower that won't stay in the lower gears.  It was slipping so I replaced the friction wheel and ever since it won't stay in the slower gears. model 536.884821  I put the old friction back in and it does the same thing. The disk it rides on doesn't look very worn. I was going to change the disk but haven't figured out how to get old one off. I bought this new about 10 years ago. Thanks

Answer
Hi Roger,

I would check to see if there is a locking tab, linkage or slot that is worn, broken or missing.  When the rubber wheel is set at a certain point on the metal disk it should stay there.  Try to move it by hand and look at why it moves away.  Check the selection lever assembly also.  

Let me know how you make out.
Michael