What is Wrong With My Mower: Quick Steps to Fix a Non-Starting Lawn Mower.

So you are trying to get the lawn mowed, and your trusty mower won’t start?

How frustrating! 

The lawn needs to be mowed, but the tool you need the most is not up to the task.

We have all been there.

Good News! Most of the time a mower will start after some basic troubleshooting.

So what should you do next?

Here are a tips on some quick troubleshooting.

If you have a push mower this can be pretty simple.

Let’s take a look at the 5 steps you can take to get your mower up and running.

 Start with the basics…. does it have gas in it? 

 Silly question, I know, but double check. 

If it has gas then it's….

 Time to check the air filter 

Take the air filter cover off, and remove the filter. 

The air filter cover will be a plastic rectangle usually on the left or right side of the motor. Though, sometimes they are on the front. You may need a screwdriver to get the cover off, but most of the time they pop off easily, or have a fastener that can been removed by hand.

Now remove the filter, it could be stopped up with debris and this could be the problem, lightly tap the filter against a concrete surface to remove the debris, then use a vacuum cleaner to clean the rest of the debris.

While the filter is off try to start the mower quickly. Sometimes the filter gets covered in fuel, or is just too dirty for it to start. 

Not recommending this, but in my experience have run a push mower for over a year with no air filter. I had to remove it to start the mower. Here’s the thing, the mower deck fell apart before the engine ever did.

IF the filter is torn, or your mower only starts when it is off you will need to replace. The Home Depot, Lowes, your local hardware or auto store should stock them. If you have time to wait, do a search online, enter the mower make and model into Google and you should be able to find it. 

If you are having difficulty with the filter check out this lawn mower air filter guide.

 Still nothing? Try Starter fluid 

Bad gas, clogged lines, and flooded motors are common issues for a mower not starting. 

Now that you have cleaned the air filter, try spraying some starter fluid into the engine.  

Behind the air filter there is a hole. Spray the starter fluid for 2-3 seconds into the hole behind where the filter sits . Then quickly try to start the mower. 

It would be best if someone helped you pull on the starter cord repeatedly while you spray the fluid into the engine.

Most of the time this will get it started. Once you get it running, spray some of the carb cleaner into the carburetor while it’s running, this will clean the carb and prevent issues down the road. 

Careful while you do this the blade is spinning!

 Nothing again? Clean the carburetor and gas lines 

Water in the gas line, or just plain bad gas will prevent the mower from starting. 

In most cases you can remove lower part of the carb by removing one bolt, which is located at the lowest part of the carb, see the photo below.  

But first! You will need to drain the gas tank, assuming you have bad gas or water in the tank, you need to empty the entire tank.

Now that the gas has been removed, its time remove that bolt at the end of the gas line below the air filter.  You can undo the bolt (see photo below) while the carb is still mounted on the mower. Keep in mind gas will come out. Once the bolt and reservoir are removed, flush the lines with good gas (safely and legally). Also clean the gas bowl with good gas. 

Put it all back together, and fill it with good gas. Will it start now?If not, cleaning the entire carb takes longer, but may be necessary. Use this guide to do a complete carb cleaning.

By now I assume most of you are cutting your gas, but if none of that works….

 It’s time to check the spark plug 

The spark plug will be on the front face of the engine and will have a rubber boot with a wire coming out of it that is connected to the tip of the spark plug. Make sure that rubber boot is connected properly. 

Try starting again, if you still have no luck. 

Most people don't know this, but it’s time to remove the spark plug and replace it. You will need a spark plug wrench. If you don’t have one they can be purchased in the lawn and garden section of any major store, or at any auto parts store. 

Remove the plug and take it to an auto parts store, and they will be able to match it up with the correct plug. Reinstall the new plug and try to fire it up again. 

Sadly, if you are still here, then you could have more serious issue such as an internal motor problem or a bad carburetor. 

Then it’s time to take it to a professional.

Faq: How to Troubleshoot a Lawn Mower That Won’t Start

What are the first things I should check if my lawn mower doesn't start?

Check the fuel level and quality, inspect the spark plugs and air filter, and ensure the battery is charged.

How much does a typical lawn mower tune-up cost?

A lawn mower tune-up typically costs between $20 and $250.

What should I do if there is water in my lawn mower's fuel tank?

Drain the old fuel, dry the tank using compressed air, and refill with fresh fuel.

Where is the air filter located in my lawn mower?

The air filter is usually located near the top of the engine, behind a removable cover.

How do I check if my lawn mower's fuel filter is clogged?

If fuel isn’t reaching the engine, try tapping the side of the carburetor. If no improvement, the filter may need replacement.

What steps should I take to clean my lawn mower's spark plugs?

Remove the spark plugs, clean off debris with a wire brush, check the gap, and re-install or replace if necessary.

How do I safely clean the underside of my lawn mower?

Turn off the engine, disconnect the spark plugs, and use a scraper or hose to remove debris.

What's the point?

If you have used these 5 Steps,

1. Check for gas
2. Check the air filter
3. Try starter fluid
4. Clean the carburetor
5. Change the spark plug

And it still won't start you may need a new mower.

Here's why, in most cases when it comes to a push mower it is not worth spending the money to have a professional repair it. A decent push mower can be bought for $200-$500. 

IF you drop it off at the lawn mower shop it’s going to be a minimum of $50 to look at it ,and before you know it you could possibly have a $200 repair bill in a mower that is not worth that.

Quick Summary:

I hope these tips helped out, and get you back running again.

Good Luck!