Toro 77501 Operator's Manual page 75

The machine does not drive.
The bypass valves are open.
The traction belts are worn, loose, or
broken.
The traction belts are off the pulleys.
The transmission has failed.
The machine vibrates abnormally.
The cutting blade(s) is/are bent or
unbalanced.
The blade mounting bolt is loose.
The engine mounting bolts are loose.
The engine pulley, idler pulley, or blade
pulley is loose.
The engine pulley is damaged.
The blade spindle is bent.
The motor mount is loose or worn.
The cutting height is uneven.
The blade(s) is not sharp.
A cutting blade(s) is/are bent.
The mower is not level.
An anti-scalp roller (if applicable) is not set
correctly.
The underside of the mower deck is dirty.
The tire pressure is incorrect.
A blade spindle is bent.
3464-621A
Possible Cause
Possible Cause
Possible Cause
Close the tow valves.
Contact an Authorized Service Dealer.
Contact an Authorized Service Dealer.
Contact an Authorized Service Dealer.
Install new cutting blade(s).
Tighten the blade mounting bolt.
Tighten the engine mounting bolts.
Tighten the appropriate pulley.
Contact an Authorized Service Dealer.
Contact an Authorized Service Dealer.
Contact an Authorized Service Dealer.
Sharpen the blade(s).
Install a new cutting blade(s).
Level the mower from side-to-side and
front-to-rear.
Adjust the anti-scalp wheel height.
Clean the underside of the mower deck.
Adjust the tire pressure.
Contact an Authorized Service Dealer.
Page 7–3
Corrective Action
Corrective Action
Corrective Action
Troubleshooting: Storing the Battery