I have a toro zx4820 with a Kawasaki 22 Hp motor, not a 21.5, and it has 2 belts, 3 blades, and I need the drive belt configuration. I tried to take the requested picture, no way does it show my area

Try rolling when you engage instead of in the still position may be too much on the motor, either that the belt is loose or needs to be replace. Or u need a carb adjustment at the idle.

Lift front of machine and secure,

Use a pipe wrench over top of blade and against deck, to keep blade from turning,

Use 1/2 " breaker bar to loosen bottom bolt,

Remove blade,

If the bottom bolt doesn't loosen, you may need a wrench at top of deck, above the bottom bolt, to loosen the bottom bolt.

Replace, or sharpen blades, install in reverse order.

GOOD LUCK FRIEND.

the should be a plastic cover under the engine

Please see page 21 of your owner's manual. Husqvarna manuals are some of the best I have seen.

http://www.husqvarna.com/ddoc/HUSO/HUSO2010_USen/HUSO2010_USen__532436505.pdf

The Toro 20016 mower is a front wheel drive mower and fairly simple to change the belt on. Start by disconnecting the spark plug to prevent start ups while working on the machine.

Remove the blade and adapter. The adapter includes the pulley for the belt.
two screws under the mower, with 3/8 heads hold the black cover over the belt. remove the cover and now you will see the transmission
The transmission, depending on the year of your machine will have a guard holding the belt on. Bend or remove the guard to remove the belt. Install you belt in reverse order.

You can get parts and special tools like the blade stop at a store like www.arcolawn.com

You can use a puller.or take the blade off and rethread the bolt back into crank about a 1/4 of an inch from bottoming out then hit the bolt with a hammer.should pop off.

For removing/replacing the deck belt, the general method is:

1. turn off engine, remove key and set parking brake
2. disengage blade by putting blade engage lever into off (disengaged) position
3. lower the cutting deck to the lowest position (closest to the ground)
4. relieve the belt tension (depending on the model, use a 3/8 inch ratchet set to tighten in the square hole of the idler bracket)
5. remove and replace the belt

NOTE: it's not necessary to completely remove the cutting deck.

Useful diagrams for removing the cutting deck, http://216.213.143.2/ProAuthor/ManProc.cfm?ManualID=425&ProcID=14794

For deck belt diagrams, http://216.213.143.2/ProAuthor/ManProc.cfm?ManualID=425&ProcID=14796

If the transmission drive belt needs to be replaced, several components must be removed and special tools (i.e. air/impact wrench) used in order to change the tractor's transmission drive belt. See an Authorized Toro Service Dealer to have your drive belt replaced.

Wait until the mower cools off

1. Remove the drive belt cover from the top of the mower
2. Tip the mower up, being careful to not go too far or the oil and fuels may spill out
3. Remove the mower blade - as I recall the bolt is 5/8" (could be 9/16") You will have to hold the blade from turning (if you have impact tools, this will be much easier)
4. Remove the blade
5. Pull the pulley out or off and remove the belt - be careful to not lose the crankshaft "woodruff" key - it's the little piece of half/moon shaped metal that keeps the pulley from spinning on the crankshaft.
6. Reverse the steps to reinstall

You MUST make sure the blade is tight when you reinstall it. Also, the blade usually fits over a couple of pins - make sure they are lined up properly and the blade is installed right-side up.

Direct-Drive Motors are linked directly to the blade and transfer all of the motor’s power to the blade. Belt-Drive Motors have a belt that transfers power from the motor to the blade. In belt drive systems, the motor can be offset away from sawdust generated during operation, causing the motor last longer. Belt drive systems require slightly more preventive maintenance than direct drive systems. So you'll need to check the belts for wear and proper tension periodically.