When your mower refuses to start, a systematic approach to the basics can often solve the problem quickly. Learning how to start the lawn mower correctly is the first step to a healthy, green yard and can save you a lot of frustration. This guide will walk you through every step, from pre-start checks to troubleshooting a stubborn engine.
How To Start The Lawn Mower
Starting your lawn mower isn’t just about pulling a cord or turning a key. It’s a process that begins long before that first pull. Following a consistent routine ensures your mower starts reliably every time and helps prevent common problems. We’ll break it down into clear, manageable steps for both push mowers and riding mowers.
Pre-Start Safety And Preparation Checklist
Before you even think about starting the engine, take a few moments to prepare. This keeps you safe and sets your mower up for success. Rushing through these steps is a common reason for startup failures.
First, clear your mowing area. Walk the lawn and remove any sticks, toys, rocks, or debris that could become dangerous projectiles. Always wear sturdy closed-toe shoes and safety glasses for protection.
Next, perform a quick visual inspection of the mower itself. Look for obvious issues like loose wires, cracked spark plug boots, or leaking fluids. Check that the blade is securely attached and not damaged. A simple visual check can reveal problems that would otherwise stop your mower from starting.
Essential Safety Gear
- Sturdy, closed-toe shoes with good grip
- Protective safety glasses or goggles
- Hearing protection, especially for louder riding mowers
- Long pants to protect your legs from debris
Step-By-Step Guide For A Push Mower
Most residential lawns use a standard push mower with a recoil-start engine. The process is straightforward if you follow the right order. Here is the definitive step-by-step method.
Step 1: Check And Add Fuel
Old or contaminated fuel is the number one cause of starting problems. Gasoline begins to degrade in as little as 30 days. If the fuel in your tank is from last season, drain it and use fresh, clean gasoline. For mowers with a 4-stroke engine, use unleaded gas with an octane rating of 87 or higher. Ensure you fill it to the proper level—don’t overfill.
Step 2: Check The Oil Level
Most small engines have a “dipstick” for checking oil. Locate it, wipe it clean, reinsert it fully, and then pull it out again to check the level. The oil should be between the two marks on the dipstick. If it’s low, add the type of oil recommended in your owner’s manual. Too little oil can cause severe engine damage, and some mowers have a safety switch that prevents starting if oil is critically low.
Step 3: Prime The Engine (If Equipped)
Many mowers have a small rubber primer bulb. Press it slowly 2 to 3 times. You should see fuel moving through a clear fuel line. This sends a small amount of gasoline directly into the carburetor to help with the initial startup. Do not over-prime, as this can flood the engine.
Step 4: Set The Throttle And Choke
Move the engine speed control to the “fast” or start position. If the engine is cold, you will need to use the choke. Set the choke lever to “Full” or “Closed.” This restricts air flow to create a richer fuel mixture for a cold start. If the engine is warm from recent use, set the choke to “Open” or “Off.”
Step 5: Pull The Starter Cord
Firmly grip the handle. For a steady pull, you might brace one foot on the mower’s deck. Pull the cord straight out with a swift, smooth motion—don’t yank it violently or pull at an angle. If the engine doesn’t start after 2-3 pulls, pause. Repeatedly pulling without success can flood the engine. Wait a minute, then try again with the choke in a different position.
Step-By-Step Guide For A Riding Lawn Mower
Starting a riding mower or lawn tractor involves a few more steps due to its larger size and added safety features. The key is understanding the sequence its computer requires.
Step 1: Perform The Pre-Start Checks
Complete all the checks mentioned earlier: fuel, oil, and a clear deck. For a riding mower, also check the tire pressure and ensure the battery terminals are clean and tight. A weak battery is a frequent culprit for no-start issues in riding mowers.
Step 2: Engage The Parking Brake
This is a critical safety step. Always set the parking brake fully before attempting to start the engine. Most modern riding mowers have a safety interlock that will prevent the starter from engaging if the brake is not set.
Step 3: Adjust The Controls
Set the throttle lever to about the halfway position. Make sure the attachment clutch (for the blade) is disengaged. The PTO (Power Take-Off) lever or switch should be in the “Off” position. You never want the blades to engage as soon as the engine starts.
Step 4: Turn The Ignition Key
Insert the key and turn it to the “On” position. You should see dashboard lights illuminate. Wait a moment for the fuel pump to prime (if equipped), then turn the key fully to “Start.” Release the key as soon as the engine cranks over; it will spring back to the “On” position. If the engine doesn’t start after 5 seconds of cranking, release the key and wait 30 seconds before trying again to avoid overheating the starter motor.
What To Do When Your Lawn Mower Won’t Start
Even with perfect procedure, mowers can be stubborn. If your mower won’t start, don’t panic. Work through this troubleshooting list in order. Most problems have a simple fix.
Check The Obvious First
- Is there fresh fuel in the tank?
- Is the spark plug wire securely attached?
- Is the battery charged (for electric-start models)?
- Is the blade disengaged or brake set (on riding mowers)?
- Is the fuel valve (if present) in the “On” position?
Diagnose Common Problems
If the basics check out, its time to look deeper. Listen to what the mower is telling you when you try to start it. The sound it makes—or doesn’t make—is a big clue.
If the engine doesn’t make any sound when you turn the key or pull the cord, the issue is likely electrical or a safety switch. Check that all safety interlock switches (seat, brake, blade) are functioning. For a pull-cord mower that is silent, the recoil starter assembly could be broken.
If the engine cranks or pulls over but won’t “catch” and run, the problem is usually related to fuel or spark. The engine is turning but not firing. This is where you should focus on the spark plug and carburetor.
Essential Maintenance For Easy Starting
Regular, simple maintenance is the best way to guarantee your mower starts on the first pull every spring. A little care goes a long way in preventing the most common starting issues.
End-Of-Season Preparation
How you store your mower for winter directly impacts how it starts in the spring. Never just park it in the shed with a full tank of gas. Follow these steps instead:
- Add a fuel stabilizer to a full tank of gas and run the engine for 5 minutes to circulate it through the carburetor.
- Disconnect the spark plug wire and drain or run the engine until it stops to use up all fuel in the carburetor bowl (optional but recommended).
- Change the oil and clean or replace the air filter.
- Remove the spark plug, add a teaspoon of oil into the cylinder, and pull the cord slowly a few times to coat the cylinder walls. Reinstall the plug (but not the wire).
Beginning-Of-Season Tune-Up
When you’re ready for the first mow of the year, a quick tune-up will ensure a smooth start. Your pre-season checklist should include:
- Install a new spark plug. This is a cheap and highly effective upgrade.
- Change the oil if you didn’t at the end of last season.
- Clean or replace the air filter. A dirty filter restricts air and causes starting problems.
- Check the blade sharpness and balance. A dull blade makes the engine work harder.
- Fill the tires to the correct PSI for even cutting.
FAQ: Common Lawn Mower Starting Questions
Here are answers to some of the most frequently asked questions about getting a lawn mower to start.
Why does my lawn mower start but then die immediately?
This often points to a clogged carburetor or a dirty fuel filter. The engine uses the fuel in the carburetor bowl to start, but then it cannot draw a fresh supply from the tank. Cleaning the carburetor or replacing the fuel filter usually solves this. A faulty choke that doesn’t open after startup can also cause this.
How do you start a lawn mower that has been sitting all winter?
First, drain any old gasoline from the tank and carburetor. Add fresh fuel. Check the oil level and top it up if needed. Inspect the air filter and clean or replace it. Install a brand new spark plug. Prime the engine, set the choke, and it should start after a few pulls. If it doesn’t, the carburetor jets are likely varnished from old fuel and need cleaning.
What is the correct way to pull a lawn mower starter cord?
Use a smooth, steady motion. Don’t yank it with all your strength or pull it out to its absolute limit. Grip the handle firmly, brace your other hand on the mower handle, and pull straight out in one fluid motion. Let the cord rewind back gently; don’t let it snap back on its own, as this can damage the recoil mechanism.
Why won’t my electric start lawn mower turn over?
For a mower with a key or button start that does nothing, the battery is the first suspect. Check the battery terminals for corrosion and ensure they are tight. Test the battery voltage; it should be above 12.6 volts for a 12V system. If the battery is good, check the fuse and all safety interlock switches (seat, brake, PTO).
Following these steps will make starting your lawn mower a quick and reliable task. Remember, consistency is key. A regular maintenance schedule, using fresh fuel, and proper storage will prevent most problems before they begin. If you encounter a persistent issue, refering to your model’s specific owner’s manual is always the best course of action.