Craftsman self propelled lawn mower wheels locked up stuck, drive pulley locked

Hi,
Eager 1 6hp craftsman 22". When i engage the drive, with the wheels in the air, the drive pulley rotates and the wheels rotate. When i put it on the floor everything stops rotating. Raise it in air, still stuck, push the tire with my feet a couple of times and starts rotating again. Lay it on the floor and the drive pulley, belt, and the wheels lock. The belt has tension and tries to rotate slowly when the drive pulley is stuck. I checked inside the tranny and all the gears have teeth. What is causing the pulley to be stuck? Despite spending so much time I can't figure out.

 

Could be bad bearings on the axles, a worn belt, something binding in the tranny, etc...

 

What do you mean by worn belt? The belt tries to rotate a little bit, but the pulley is stuck. How can it be bearings? Wheels rotate freely when not engaged in drive.

 

The transmission axles turn gears right? The wheels don't attach to the transmission axles, do they? Normally they don't and I don't know what model mower you have, so that's all I can go on.

A worn belt can be tight but still slip. If it is too thin, it won't grip the sheaves and will slip. If the pulley is locking up as in you can't turn it by hand, then it sounds like bearings or internal tranny problems.

 

My stepson has a self propelled craftsman mower and it is constantly chewing up the teeth on the inside of the drive wheels. His mower does as you describe; won't pull the mower when on the ground but will drive the wheels when you lift the front off of the ground. IMO the plastic teeth is a poor design. You can buy replacement wheels at Sears. I just checked on them yesterday and they were $16 each.

 

So, I should just clean and wd40 the bearings and try it? I found a small piece of metal from the transmission box when i opened it. I took it out and and still the pulley is stuck and only rotates when it is in air after i push the wheels with my feet. Once it rotates in air, it keeps rotating; it does not rotate intermittently.

 

I tried so many combinations. I finally removed the washer from the worm gear's bottom, but kept the bearing and tightened everything. But when I tighten all four screws of the trans case, the pulley becomes locked/stuck. So, i tightened two diagonal screws and left the other two diagonal screws loose. Now it has nice pulling. But i can't figure out what is causing this problem. The wheels are OK.