Symptoms
- Engine runs fine but blades don't spin when PTO is switched on
- May hear a clunk or hum from the clutch area with no blade movement
- Worked before, or blades run weak/intermittent
- No blade engagement even at full throttle
Likely causes
- CommonBroken or slipped mower deck beltThe belt connecting the engine pulley to the blade spindles can break or come off its pulleys.
- CommonFailed electric PTO clutchThe electromagnetic clutch that engages the blades wears out over time and stops engaging.
- PossibleBlown PTO fuseA dedicated fuse for the PTO circuit can blow, cutting power to the clutch.
- PossibleWorn PTO switchThe dash switch or lever that activates the PTO can fail internally.
What to do
- Turn off the engine and check under the deck for a broken or dislodged drive belt.
- Check the fuse box for a blown PTO fuse and replace it with the correct amperage if needed.
- With the engine off, examine the PTO clutch for a burnt smell, visible damage, or looseness.
- Test PTO clutch engagement by listening/feeling for a click at the clutch when the switch is activated with the engine running.
- Check the PTO switch itself for continuity if the clutch doesn't click at all.
- Replace the belt, fuse, clutch, or switch based on what's found faulty.
Tools and parts
- Multimeter
- Wrench set
Mower deck drive beltSearch: “riding mower deck belt”
PTO clutchSearch: “riding mower PTO clutch replacement”
When to call a pro
PTO clutch replacement involves electrical and mechanical work best handled by a small engine shop if you're not experienced.
Safety
Use caution
Always turn off the engine and remove the key before reaching under the deck.