How To Start Your Sitting Lawn Mower That’s Been Gathering Dust

How To Start Your Sitting Lawn Mower That's Been Gathering Dust

Maybe it’s the first time the grass needs a trim this Spring, and you’ve saved your mower from the depths of the garage.

Perhaps you’re doing a big clear-out and found the mower you’d forgotten about buried under a pile of discarded mess. Either way, it’s been sitting collecting dust for some considerable time, and now it doesn’t want to start. 

Whatever you do, don’t condemn it to the scrap yard just yet! There are plenty of tricks and tips to bring this machine back to life.

So don’t give up on it, not just yet. In this article, we’ll go over the many ways you can get that mower trimming your yard in no time at all. 

Just remember, mowers are machines, with engine parts and sharp blades. So safety should be taken seriously. Always wear safety glasses and gloves, and take the utmost care when handling the mower. 

1. Check And Change Your Oil 

Usually, I would always recommend that you change your oil about 60 minutes after your mow, but since it won’t turn on and you can’t mow, let’s check it straight away.

I’d definitely be taking a peak at the oil first when the mower has been sitting for extended periods of time. 

You’re looking for a good quality oil that is free from residue. And you’re checking that there’s enough oil in your mower. If your oil is a dark and dingy color with bits floating about in it, then it’s probably time to change the oil.

Ideally, you’re changing your oil at least twice a year. I do this at the start of the lawn-mowing season, and then right at the end before it’s tucked away for its Winter hibernation.

If you haven’t changed your oil for a while, I’d do so now, even if that isn’t the actual issue preventing your mower from turning on, it’s still going to help. 

They don’t require a massive amount of oil, and it’s a pretty cheap and easy do-it-yourself job. For your standard mower, this is likely to take you just 10 minutes. 

Disposing Of Mower Oil

The oil you collect has to be disposed of in the correct manner, so its important to know how to do so properly. 

The first thing you’ll need is a plastic container, it’ll need to have a sealable cap that won’t leak. I usually find a Gatorade bottle works well.

Then you’ll need to take it to a local auto shop that will be able to dispose of it. If your local won’t accept it, then you’ll need to see if your city dump will. 

2. Check Your Gas Tank

Complaining that your mower is broken without checking the gas tank is similar to moaning that your lamp is broken without checking you’ve plugged it into the outlet.

Make sure that you are checking the basics. And ensuring that your mower has a full gas tank is the simplest place to start. 

Now gas isn’t the stablest of substances so if you’re mower isn’t brand new (made it to over 30 days old) then you’ll want to empty your tank and start over. There are two ways you can empty your tank. 

  • The Easiest Way – Tip over your mower and hope that the gas dumps out. 
  • The Harder Way – If this doesn’t work then you’ll need to siphon out the gas. 

Once the old gas is out, you can refill it with fresh. The only exception to this rule will be if you have put a fuel stabilizer into your gas before it was left to sit. 

Recommendations For Hassle-Free Gas

For my mower, I always use TruFuel. Most standard local box and hardware stores offer it. This is your old-fashioned type of gasoline where ethanol isn’t added.

You usually don’t need to add a fuel stabilizer and my mower always tends to roar to life on the first try. 

It does cost a bit more than your standard gasoline, but it’s a price I find I’m willing to pay to eliminate the hassle of changing the gas come Spring. 

3. Change Your Air Filter

Don’t start sweating on me now, it’s really not as difficult as it sounds. But if you’ve tried the first two steps and your mower is still being stubborn, then it could be because your air filter has got clogged up. 

Your engine vitally needs oxygen for combustion, so if your air filter is preventing that then it’s going to do one of two things. One, not work effectively, or two, give up altogether. 

Trying to clean a dirty air filter is honestly just not worth the time it’ll take you to do so. And if you miss even just one small spec of residue, dirt, or dust, it’ll ruin your engine. 

It’s a much better idea to just replace the whole thing. 

If your mower starts up but then conks out on you pretty quickly when you start trimming your grass, that’s a telltale sign that you’ve got a clogged-up air filter. 

Where To Get An Air Filter For Your Mower

So you know you need a new air filter but where can you purchase your replacement? Pretty much any box store is likely to have the correct size that you’re after. And it’ll probably cost you just $10. 

Replacing your filter should become an annual habit for proper mower maintenance. 

Though it may sound like a complicated job, it really isn’t. It’s a case of finding your air filter and then just swapping it out with a new one. 

This might not always be the sole cause of your troubles, but if you’ve got a mower that won’t start, I’d confidently hedge my bets that it needs a new air filter. 

How To Start Your Sitting Lawn Mower That's Been Gathering Dust (1)

4. Replace Your Spark Plug

A mower’s spark plug is typically located at the front end of your mower.

You should be able to notice it fairly easily as it will have wire attachments to it. In most cases, it’ll have a black rubber cover over it to keep it safe from dirt and debris. 

You’ll want to check the wires and the connection. Are they in good shape? Is it connected correctly? 

Then you’ll need to check the actual plug itself. 

To remove your mower’s spark plug, you’ll need a socket wrench. Unfortunately, I can’t tell you the exact size wrench that you’ll need, that will be a case of trial and error.

But once you’ve got the correct size, it should take no more than a few mere twists to get it out. 

Once it’s removed, it should be pretty clear if you’ll need to replace it. If the business end of the spark plug is discolored or corroded, then you need a new one.

You can try cleaning it up a bit and seeing if that makes a difference before purchasing a new one if you wish, but I tend to find that it rarely makes a difference. 

How To Replace Your Spark Plug

You’ll be happy to hear that, once again, this scary-sounding job is actually much simpler than it looks. You need only your plug and your wrench and to slot the new one where the old one came out. 

Just make sure that you don’t overtighten it when you replace it. I tend to replace the spark plug at least once every two years for good maintenance.

For me, when I’ve exhausted all the above options, the spark plug tends to be the pesky culprit for a no-start. 

You can usually find a spark plug in most hardware stores, but if you can’t a quick search on Amazon should do the trick. 

Safety Notice – If you are doing any troubleshooting on your mower engine, always ensure your spark plug is disconnected so that the engine cannot turn on/start while you are doing work on it. 

5. Tighten Your Brake Cable

Your mower is unlikely to start if your brake cable is loose. You’ll need to take a look at the tension on the brake.

You can do this by pulling on the handle with one hand and then with your other hand pulling the cable to see if it’s nice and tense or not. 

If it’s wibbly and wobbly like a bowl of Jell-O rather than tight and unmoving, then it’ll need tightening up. To sort this, you should only need a crescent wrench and a few vice grips. 

6. Check The Carburetor 

It’s pretty common for your mower to stay idly sleeping rather than roaring to life when your carburetor is stinking dirty. You’ll want to check to see if your carb has corroded or if it’s all clogged up with the fuel’s sticky residue. 

If it’s not corroded and just very dirty, you can try just giving it a good old clean. My advice would be to leave it soaking overnight in vinegar. If this doesn’t work, or if it’s corroded, you’ll need to replace it. 

Can You Do It Yourself? 

I knew that would be your next question, and the answer is it depends. But it really only depends on your confidence levels and handy-man-skills.

This isn’t quite as easy as changing the air filter, so if you’re giving it a go yourself, I’d recommend following a Youtube Tutorial on your specific model to guide you through the process. 

What Are Your Other Options? 

If you just don’t have the time or patience to do this, then you could try using some starting fluid spray to help the issue. 

These cans will cost you less than $5. All you’ll need to do is spray the contents into your engine behind your air filter. Just make sure that you don’t spray it on your air filter. Or you’ll have to replace that again. 

It’s important to note that this will just be a quick fix though, and it won’t be a long-term solution. You’ll still need the carb replacing at some point soon when you have a little more time. 

7. Replace Your Fuel Pump 

A fuel pump does exactly what it says on the tin. It’ll pump the fuel from your gas tank into your engine. It does this from a series of three ports. 

If at any point you have overfilled the oil in your engine, the excess oil tends to leak into these ports and into your pump.

When this happens it breaks your pump and then it can’t transport that gas into the engine to start it up. 

You can check to see if your pump is working by checking the pulse port line as well as the valves and pump’s diaphragm. 

If it’s faulty it’s a replacement problem and unfortunately, there’s no way to mend it yourself. Your fuel pump can get a little pricey but it’s still significantly cheaper than purchasing a brand new mower, so it’s worth doing.

8. Check For A Broken Flywheel Key

For those who are thinking what in the world is a flywheel key? It’s the huge flat spinning wheel in your mower. When you pull the cord of your walk-behind mower, the thing that starts spinning, that’s a flywheel key. 

If you’ve recently accidentally hit a fairly hard object with your mower, you may have broken part of the flywheel key. And if it is broken, it won’t matter how hard you pull that cord, it’s not going to go. 

It’s unlikely that this will be the culprit if your mower has been sitting for a while, but if you’ve exhausted all your options, it could be worth a look. And at least you’ll know for the future, right? 

Although, it’s probably time that I break the bad news, removing the flywheel to get to the key is no easy job. It’ll require a whole lot of deep breaths and patience. It’s a pretty tedious job.

This is because the nut you need to remove is on there pretty tightly. You may also need another set of hands to hold the flywheel still while you loosen it. I say may, you will. You will need that extra set of hands. 

What Not To Do When Replacing This Part

A lot of do-it-yourselfers tend to try and place a piece of apparatus between the wheel blades to keep them still. Please DO NOT do this. 

Either get someone else involved or use a clamp. The method mentioned above is the perfect way to break a blade, and you’ll certainly shed a tear when you see how much they cost to replace. 

I’d recommend watching a Youtube Tutorial for your model mower too so that you know exactly what you need to be doing. 

How To Start Your Sitting Lawn Mower That's Been Gathering Dust (1) (1)

9. Don’t Give Up

The number of people that tell me that they’ve replaced their mower because it stopped working throughout the winter is actually astounding. And it’s like a dagger to my heart.

Lawn mower purchases are not cheap, and it’s so likely that a little bit of TLC would have just brought that sitting mower straight back to life. 

Of course, there will be times when your mower has just breathed its last breath, and not much more can be done. But this is usually the case with much older and well-worn mowers.

If your mower has not yet even seen its 4th/5th birthday then do not discard it just yet. 

Frequently Asked Questions

Is It OK To Mix Old & New Gas? 

No. You should never mix the two. There are quite a few reasons for this. The old gas has probably already lost its combustibility. It can also lead to sputtering.

And the old gas may stop your mower from being able to start. 

Can A Lawn Mower Last 20 Years?

If you are maintaining your lawn mower correctly, it can be easy to get at least 10-15 years out of your mower.

Obviously, there are lots of factors that will determine the lifespan of your mower, but it is possible to stretch to 20 years if you are consistently changing damaged parts and fixing issues as they arise. 

What Side Do You Lay A Lawn Mower On? 

It’s vital that when you tip over your mower that the side with the carb and air filter faces upwards. If you do it the wrong way oil will spill everywhere. 

Final Thoughts

Hopefully, now, you have all the knowledge that you need to get that mower gathering dust to come back to life as it had never been left alone all along.

If your mower says no when you give that cord a pull, go through each of the steps one by one trying to eliminate the problem. 

In most cases, your mower will already have been resurrected by step 4. Of course, don’t be discouraged if it hasn’t by that point, keep going through the list and you should be able to find the culprit.

And of course, there could be more than just one issue, so you may need to do a couple of these fixes before you get your mower back. 

Most of these fixes are really simple to do, and if you’re still a little confused, just type the problem and the model into Youtube and you should be able to find a tutorial that will walk you through the steps that you need to take.

Most of the time, when you need to replace items, they are relatively cheap to purchase and easy to find in most stores.

So it’s such a simple and easy solution that will save you tons of money compared to just purchasing a new one. 

Leave a Comment