Well, you at least will have to pull the rear wheels and clean/lube the ratcheting spur gear, wheel gear and axle on each side. Is the drive belt in place? Does it tighten when the handle is pushed down? Do you mean the wheels won't turn when you push the mower with the engine off, or that it rolls okay but doesn't drive when you walk with it holding the handle?

The wheels won't turn when you push the mower with the engine off and it does tighten when the handle is pushed down. What kind of lubricating oil should I use?

Two kinds of grease; spray white lithium grease and a tube of white lithium grease, NLGI #1 or #2. Take one wheel off and clean all parts - wheel gear, axle bolt and axle hole. Use solvent and a toothbrush to clean all parts. Then take a toothpick and try to clean out the center hole in the ratcheting spur gear on the end of the axle as much as you can without pushing the dirt back into it. Use the toothbrush/solvent to clean the spur gear as well as you can, then stick the straw of the spray grease into that hole and blast it. The grease has a fast-drying solvent that finishes the cleaning job and leaves grease behind. Keep doing it until it looks clean coming out. By now you should be able to turn the gear in one direction and hear the ratchet clicking. Grease the axle, axle hole and wheel gear teeth with the tube grease and assemble the wheel. Turn the wheel in the forward direction and it should turn. In case there was a washer that you didn't remember where it goes, you can remove the other wheel to check. Now do the other side and it should roll. This is routine maintenance and should be done every fall.
This is all assuming that the axle turns and drive the wheels when you operate the drive. Otherwise you have a bad transmission or some other problem in the drive.
This is a dirty job. I prop up the rear of the mower with a piece of 4x4 and put several layers of newspaper under it to cover the work area. Its good to have a metal or plastic pan for the solvent and some rags for wiping. You probably should wear mechanics' Nitrile gloves because you're going to get dirty.
If the wheel is too sloppy on the axle bolt, you will have to replace the axle bolts and possibly the wheels. This is not unusual considering the age of the 20017. Probably about $50 or $60 for both sides, or $10 for the axle bolts. Some play is normal - bottom line, when the wheel gets too loose, it affects the self-propel by making the spur gear slip on the wheel teeth which are moving in and out too much.

Thanks for the advice. I am going to try doing what you said and see what happens and I will let you know the results.

I did what you said to the wheels but they still won't turn. It seems like the axle that goes from wheel to wheel and through the transmission won't turn. Do you have any other suggestions?

I played with the mower and found out when I started it and lifted up the rear wheels they moved. I loosened up the control for the pace and now it seems to work ok. I do have a couple other problems. The throttle control wire has loose play in it. Is there a way to adjust it. The other thing is the gas hose coming down from the gas tank is leaking. What is the best way to change the hose?

Well I got the fuel line replaced and put on a new blade and it works well and the engine runs good. I again want to thank saxman1for the help. He helped make it possible to rehab a mower that hasn't been used in at least 2 years. Toro does make a good mower with a great engine and now I'll make sure I will grease the wheel gears every year.

My back wheels lock up when I try to back up. Going forward rolls just fine. Any ideas? Thanks ahead for your help

This post was edited by beachbum1975 on Fri, Jul 18, 14 at 14:28