Before operating your lawnmower, it is essential that you have read and understood the instruction manual supplied with your machine.




Quick Answer

To start a petrol lawnmower, you must check the oil and fuel levels, prime the engine if required, engage the safety/start lever, and pull the starter cord firmly. If the mower is difficult to start, the start cable tension may also need adjustment.

⚠️ Safety Notice

Before starting your lawnmower:

  • Read and understand the instruction manual
  • Wear suitable personal protective equipment (PPE)
  • Operate on a clear, flat surface
  • Keep children, pets, and bystanders away
  • Handle petrol carefully — it is highly flammable

Failure to follow safety guidance may result in injury or damage.

Before You Start

Check the following before attempting to start the mower:

Engine Oil

  • Ensure the engine contains the correct oil level
  • Use the dipstick to confirm oil is between MIN and MAX marks
  • Most mowers use SAE 30 oil (or equivalent), but always check your manual

Fuel

  • Use fresh unleaded petrol (ideally less than 30 days old)
  • Ensure the tank has sufficient fuel

Starting Your Petrol Lawnmower

Step 1 – Prime the Engine (If Fitted)

If your mower has a primer bulb:

  • Press the primer bulb 3–4 times
  • This helps fuel reach the carburettor for easier starting

If your model does not have a primer bulb, skip this step.

Step 2 – Position the Starter Cord

  • Pull the starter handle gently
  • Place it into the rope guide on the handlebar
  • Ensure it is seated securely

Step 3 – Start the Engine

  1. Pull and hold the engine brake/start-stop lever against the handle
  2. Pull the starter cord sharply and smoothly
  3. Repeat until the engine starts

Cold engines may require several pulls.

Once running, keep holding the brake lever while operating the mower.

Checking Start Cable Tension

A loose or incorrectly adjusted cable can prevent the engine brake system from engaging, resulting in starting issues.

Tools Required

  • 10 mm spanner
  • 13 mm spanner

Identifying a Loose Cable

Check the cable near the handle assembly:

  • Excess slack or movement indicates adjustment is required
  • The cable should be firm but not overly tight

Adjusting the Cable



Step 1

Locate the cable adjustment bolt on the handle.


Step 2

Loosen the locking nut using the spanners.


 

Step 3

Adjust the tension:

  • Tighten or loosen until slack is removed
  • Ensure the brake lever engages correctly when pulled

Step 4

Retighten the locking nut securely.

The correct position is typically mid-way along the threaded adjustment bolt.

Frequently Asked Questions

Why won’t my lawnmower start?

Common causes include:

  • Old or stale fuel
  • Low engine oil
  • Incorrect priming
  • Loose or faulty start cable

Do all lawnmowers have a primer bulb?

No. Some models start without priming and rely solely on the choke and fuel system design.

How many pulls should it take to start?

A cold engine may take several pulls. If it does not start after repeated attempts, recheck fuel, oil, and cable tension.

Can a loose cable stop the mower starting?

Yes. If the engine brake is not fully disengaging, the engine may not start or may immediately cut out.