Other outdoor power

Hedge trimmer won't start

Gas hedge trimmers usually fail to start due to stale fuel or a fouled plug; battery models usually have a dead or disconnected battery or a safety switch not engaged.

Difficulty
Easy
Time
15–30 minutes
DIY cost
$0–$60
Pro cost
$60–$120

Symptoms

  • Pull cord does nothing on gas models
  • Battery model shows no lights or won't power on
  • Engine sputters and dies quickly
  • Blades don't move when triggered

Likely causes

  • CommonStale fuel (gas models)Old gasoline gums the carburetor and prevents starting.
  • CommonDischarged or faulty battery (battery models)Batteries lose charge in storage or wear out over time.
  • CommonFouled spark plug (gas models)Carbon buildup weakens spark.
  • PossibleSafety switch or trigger interlock not engagedMost trimmers require two-hand or interlock switches pressed simultaneously.
  • PossibleJammed blades from debrisTwigs or debris stuck between blades can prevent the motor from engaging.

What to do

  1. For gas models, check fuel freshness and replace if old.
  2. For battery models, charge the battery fully and confirm it clicks securely into place.
  3. Check that all safety switches or triggers are pressed together as designed.
  4. Pull the spark plug on gas models and inspect for fouling.
  5. Clear any debris jammed between the blades with the tool powered off and battery removed or plug disconnected.
  6. Inspect the power cord on corded electric models for damage.
  7. If a gas model still won't start, the carburetor may need cleaning by a professional.

Tools and parts

  • Spark plug socket (gas models)
  • Battery charger
Hedge trimmer replacement batterySearch: “hedge trimmer battery replacement”
Spark plugSearch: “hedge trimmer spark plug”

When to call a pro

If a gas trimmer's carburetor needs service or a battery model's motor has failed, a small-engine or power tool repair shop can help.

Safety

Use caution

Always remove the battery or disconnect the spark plug before clearing jammed blades.

Related guides

Operator provides AI-generated troubleshooting information. It can be wrong. For safety-critical, electrical, gas, structural, medical, automotive safety, or other high-risk problems, consult a qualified professional.