Small Engines (Lawn Mowers, etc.): Tiller drive selector, drive mechanism, access panels

Question
Tiller is a Yard Pro(I think MTD) 5 hp rear drive. The drive selector is stuck in "Till" ( won't move to Reverse; neutral; or forward). Any ideas?

Thanks

Answer
Without having the tiller in front of me to see the drive mechanism, I can only offer some general recommendations.  Follow from the actuation lever down to the drive.  If it enters a chaincase or goes under a cover assembly, you will need to remove whatever access panels, covers, etc. to enable yourself to view the drive mechanism.  What you are looking for is something seized.  If this tiller has a large chaincase for a transmission, the repair is better left to a competent shop because it is a fairly complicated procedure to disassemble and re-assemble these.  If it uses belts to select the direction and engagement, then you are looking for a stuck idler pulley arm.  If you can direct me to a parts breakdown (on the web) using the tiller's model number, I can try to point out the areas where seizure typically occurs.  Hope this helps.