Small Engine Mechanic how-to
How to Sharpen and Balance a Mower Blade
Sharp, balanced blades cut cleanly and protect the engine.
Quick answer
Sharp, balanced blades cut cleanly and protect the engine. In short: disconnect; mark; sharpen, then complete the remaining steps below.
Step by step
Disconnect the spark plug wire or remove the battery.
Mark the blade orientation and remove it.
Sharpen each cutting edge at the original angle.
Check balance on a blade balancer.
Grind the heavy side until balanced.
Reinstall and torque the bolt to specification.
Safety reminders for small engine mechanics
- Disconnect spark plug wires or batteries before working on blades
- Drain fuel and work in ventilated areas away from sparks
- Wear eye protection when grinding and using compressed air
- Run engines only with exhaust vented outside
Key terms
Two-stroke engine · Four-stroke engine · Carburetor · Choke · Ignition coil · Flywheel key: see the full small engine mechanic glossary.