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My Lawn Mower Starts Then Dies: What’s Wrong? (2022)

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We’re all guilty of leaving our grass to become a little, shall we claim … neglected sometimes.

But, “It’s all right”, we tell ourselves, even as it borders on jungle-level overgrowth, since any day currently, we’ll obtain a spare moment to release the mower as well as tidy points up.

And also indeed, we do at some point discover time to offer our yards some long-overdue TLC, yet just as we reach the midway factor, with thoughts of a sudsy post-job cool one rattling around our minds, something else starts rattling … the lawn mower

It sputters on for an additional pair of yards before giving up the verdant ghost, leaving us with half a putting eco-friendly that Tiger Woods would applaud, as well as half a thick jungle that not also Bear Grylls would attempt to enter.

Half a trimmed lawn is like half a hairstyle– not socially appropriate, and, frankly, terrible-looking. What are we supposed to inform the neighbors?

“Oh, yeah, sorry about this, Val, my erm … my lawn ‘s experiencing a bit of a punk rock stage presently”– Somehow, I do not assume that’s going to track.

Nope, the only option is to obtain that lawn mower going again, and also to do that, you initially require to identify the trouble, and also, secondly, fix it, which is exactly what I’m going to help you with today!

Why Is My Lawn Mower Betraying Me?

When your lawn mower starts up but reduces out before you have an opportunity to obtain anything done, the normal suspects are …

  • An unclean carburetor or an obstruction in the carburetor bowl
  • Stagnant fuel
  • Harmed or filthy ignition system(s)
  • Too much oil degrees

That may feel like one heck of a line-up, yet I’m pleased to report that they’re all extremely simple to deal with, as well as I’m going to show you how.

Carburetor Chaos

Besides being exceptionally challenging to spell, the carburetor is your lawn mower ‘s crucial component, so when your grass-eating monster starts to misbehave, all eyes must rely on the carb.


I Thought Only Old Cars Had Carburetors. What Are They Doing in Our Lawn Mowers?

The carburetor in your lawn mower does the exact same thing it does in your auto: Mixes precisely the correct amount of gas with specifically the ideal quantity of oxygen to facilitate combustion.

These small controlled surges stimulate a chain reaction that obtains the crankshaft spinning and the engine fired up, but if the fuel: oxygen proportion is off as a result of a buildup of dust on the carburetor or a blocked bowl, it can toss the entire system out of whack.

Burning will still be happening, which is why your lawn mower fires up when you pull the cable, but it’s not a lasting source of power, which is why your mower chokes minutes later.

Okay, So How Do I Fix It?

In this situation, all you need to do to revitalize your lawn mower is to provide the carburetor a complete clean, and also what far better to do that with than an aerosol can of specialized carburetor solvent?

I can directly advise WD-40 Specialist Carb/Throttle Body Parts Cleaner It’s super budget-friendly, as well as caring for both carbon pollutants and also gumming. I’ve been using it for years, as well as it’s never ever let me down.

That claimed, it does have one shortcoming … it does not have a straw applicator for accuracy usage, yet that’s okay, as there are numerous alternatives that do, such as Gumout Carb and Choke Cleaner I would certainly recommend you to grab a can of both, make use of the WD-40 for the heavy lifting, then switches to the Gumout for precision spot cleaning.

Just how To Clean Your Carburetor

Step 1. Open The Windows

Carb cleaner may be excellent for your carburetor, yet it’s heck on the lungs, so make certain you’re working in a well-ventilated location.

Step 2. Locating The Carb

Your carburetor will certainly either be bolted to the top or side of the motor. Discover it? If not, check behind or listed below the air filter.

Step 3. Remove The Fuel Line

Detach the gas container from your mower (they normally move out of place), then use a pair of needle nose pliers to vibrate the fuel line loose.

Action 4. Eliminate And Clean The Jet Screw

The jet that feeds fuel right into the car increases up as a bolt that holds the dish in the area. Loosen the jet from beneath your carburetor, and also offer it a generous spraying with your carb cleaner.

I find it’s best to make use of the accuracy applicator for cleaning up the jet networks, as the focused stream can assist dislodge debris.

For the best outcomes, you should think about making use of a carb cleaner kit , as they get here with all the unique brushes you need to rejuvenate your jet.

Action 5. Poke The Jet Channels

Take an item of cable, and even simply an unfolded paper clip, and poke it through the small holes in the jet screw, simply in instance the carbohydrate cleaner missed anything.

Action 6. Get rid of And Clean The Bowl

With the jet got rid of, the carbohydrate dish need to draw free. Spray it with lots of carbohydrate cleanser, and, if you have one, offer it a great scrub with the brushes from your carb cleansing set.

Action 7. Examine The Gaskets

The gaskets are the black, rubber O-rings that secure the distinct areas of your carburetor. Look for any type of falling apart or acnes. If you discover any, change them with fresh gaskets.

Action 8. Push The Float

When you got rid of the dish, you disclosed the carb float, a little disk connected to the remainder of the motor. Gently press it up and also listen closely. If you listen to a peaceful clicking sound, all is well. If not, you may require an expert to consider the matter.

Action 9. Place It All Back Together

Okay, so now your carbohydrate is looking glossy as well as glossy, it’s time to re-assemble. Make sure not to overtighten the jet screw, as you could remove the strings and disfigure the seal.

Step 10. Spray Some Carb Cleaner In The Intake Hole Of The Engine

The consumption hole is normally behind the air filter. Provide it a light spritzing, and also when you begin your mower up, it will certainly be pulled via the system, giving every little thing one last clean.

Step 11. Take Your Mower For A Spin

With any luck, that quick upkeep session solved your mower mishap, as well as currently you’re complimentary to reduce all the yard you want. If it really did not work, do not sweat it. We’ve got three more solutions to attempt.

Geriatric Gasoline

You may not realize it, however much like those plums shriveling up in your fruit bowl, gas has a rack life. Over time, the volatile compounds vital to burning thin out, which, understandably, can have a negative effect on engine performance.

pouring gasoline into mower

When the top quality goes down below a specific threshold, it starts to harm the interior parts of your electric motor. What’s even more, it leaves a gummy down payments on surface areas, which, if left unaddressed, can hamper gas flow, causing, you’ve thought it … sudden mechanical failures.

Obtained it! However, How Do I Fix It?

If you’ve got, state, much less than half a tank left, you may be able to get away with weakening it with fresh gas, thereby strengthening the combustive homes. But if you’ve obtained over half a tank left, I’m afraid you’re mosting likely to have to deal with the components (properly, of course).

Regardless of which course you wind up taking, my suggestions is to toss some type of gas stabilizer right into the mix, as well as if you’re seeking a referral, in the past, I used STA-BIL 360 Defense Ethanol Treatment and Fuel Stabilizer these things protects against deterioration and halts the build-up you’ll see making use of typical gas, ensuring your engine constantly runs buttery smooth!

Alternatively, you might do what I do now as well as use TruFuel-4-Cycle Ethanol-Free Fuel Ethanol is right stuff that creates all the issues when fuel goes stale, so eliminating it from the equation is sort of a piece of cake.

A storage tank loaded with TruFuel will certainly make it through a long, cool winter season in the shed, so when the warmer weather arrives, as well as your yard obtains a growth spurt, you can break out the mower sans missteps!

Cards on the table, TriFuel is a bit extra costly than the standard gas/stabilizer combo, however in my viewpoint, the dependability as well as tranquility of mind it brings is well worth the costs. It gets my 140cc Black+Decker mower terminated up with a single pull every single time– an actual shoulder saver!

Trigger Plug Panic

As soon as the carburetor has actually mixed the gas and air, it’s the spark plug’s time to radiate.

These incendiary little components provide the stimulate that fires up the fuel/air mixed drink, thus powering your mower ‘s engine

spark plug

As a pivotal part of the combustion process, should they fall under disrepair or probably obtain a little dirty, it can cause the annoying start-stop mower behavior that brought you to this write-up.

And also What About the Fix?

As long as your stimulate plug isn’t entirely covered with a stubborn carbon build-up, you can merely remove it, offer it an extensive tidy, then change it. Hopefully, that will certainly smooth the burning process out as well as return your mower to its former glory.

If you do discover a great deal of soiling on your ignition system, it’s best to call it stops as well as order a brand-new one.

How to Remove as well as Clean A Spark Plug

Step 1. Finding Your Sparky

Ignition system are commonly front as well as fixate your mower, so they’re not tough to find. Look for a component covered with black cabling at the front end of the engine.

Step 2. Removing Your Spark Plug

Eliminating your trigger plug requires an outlet wrench of a specific size, so have a fast thumb with your individual manual, and also see what information you can dig up.

Don’t worry if you’ve misplaced your handbook, as you can acquire a universal trigger plug wrench right here

Once you’ve obtained the needed tool, pull the black cable without the plug, and make use of the wrench to loosen it from the engine.

Action 3. Cleansing Your Spark Plug

I utilize typical multi-use WD-40 and a tiny wire brush for cleaning my spark plugs.

Begin by spraying the plug down with your cleansing remedy, then leave the chemicals to function their magic for a few mins. Next off, take your small cable brush, as well as offer your sparky a good scrub to remove any dirt or carbon deposit.

As soon as the debris has been perturbed, clean it away with a soft rag to cover this step up.

Step 4. Replacing your ignition system

If you’re renovating your old ignition system, simply put it right into the completion of your wrench and spin it back into location (not as well limited).

Things are a little bit a lot more complicated if you’re suitable a substitute plug, yet stick to me, and we’ll have it arranged in no time at all!

  • Initially, you have to “void” the plug, which basically means that you are thinning or broadening the void in between both electrodes at the end of the plug to match the needs of your mower To do so, you’ll need one of these convenient CTA Tools ignition system gapper s.
  • Check the recommended plug space in your customer manual, then run your ignition system appear in the space between the electrodes. Transform it up until you feel resistance, then check the dimension on the face of the device.
  • If the void isn’t quite large sufficient, you can use the hole in the paper to tear the leading electrode upwards, as if you’re breaking the cap on that chilly one you were desiring for earlier (and still are). To make the gap smaller, all you have to do is use the gapper device to lower on the leading electrode.
  • When gapping is full, you can establish the plug in area as normal. Take your time, and also do not require it. You require to obtain the threads in simply the appropriate location to secure it properly, and also bear in mind, it shouldn’t be as well snug, as over tightening can damage the plug seal.

Ignition System Advice For The Future

A good general rule is to change up your trigger plug a minimum of when every two years, however I such as to bump it approximately once yearly as a component of my basic upkeep routine.

Oil Overload

If you’re anything like me, you really felt the impulse to load your oil storage tank to the border. “Gosh”, you assume … “Amn’t I an accountable device proprietor!”, but surprisingly, there is something as also much oil.

You might have noticed that before your mower made a decision to take a siesta, it was spewing some white smoke, which is a telltale sign that you did obtain a little overzealous with your oil.

The factor your mower seems to be working penalty in the beginning is that the excess oil is yet to hush the engine, and also I recognize “sink” is a strong word, yet this isn’t as grave a circumstance as it indicates. Let’s have a look at exactly how you can make points right once more.

Fixing Your Oil Surplus

The most convenient method to resolve this concern with a walk-behind mower is to simply pop the top of your oil storage tank, tip your mower on its side, and also drain pipe’s a few of the components; nonetheless, this can get rather unpleasant.

A much cleaner method to decrease your oil level is to make use of an oil extractor pump These things allow you to siphon the oil away without spilling it, indicating (as long as it’s tidy) you can use it once more at a later date.

Beware not to draw out way too much oil, though, as that can be also worse for your lawn mower than overfilling it.

Once you’ve sorted your oil degree out, fire your mower up and also watch out for the feared white smoke. If it seems to be running clear, then you’ll understand the issue has been rectified, and you can level your rickety lawn post-haste.

How To Prevent This Oily Issue Repeating Itself

Currently that your motor is feeling its old self again, relax, examine the oil with your dipstick, and also keep in mind down the level. You can use this for future reference.

When the time concerns replenish your oil get, the trick is to take it great as well as easy. Rather than pouring your oil into the tank willy-nilly, pour it in a little at once, stopping briefly periodically to examine the degree with your dipstick.

None of These Fixes Worked. What Do I Do?

Lawn mower still giving you despair after trying all four of these repairs? Dang!

Starting and passing away quickly thereafter can be symptomatic of even more significant mower problems. They’re incredibly challenging to detect, as well as much more difficult to take care of.

So, I’m scared it may be time to attack the bullet, call a professional, and also have them have a look at your naughty equipment. The trouble might be …

A Defective Choke

The choke restricts the airflow in the carburetor to maximize the gas: air proportion.

If it’s enabling the passage of too much or also little air, the engine won’t be working efficiently, and also, in many cases, burning may not take place in any way, causing the unexpected mower death we’ve been attempting to resolve today.

A Spent Carburetor

Sometimes, despite just how much you scrub your carb, the damages is currently done, and also a replacement is the only method to get your turf gobbler purring again.

If you’re specifically useful, you might be able to make the switch on your own, but, in my viewpoint, it’s best left to an expert.

A Blocked Gas Line Or Tank

Engines need consistent gas flow to run successfully. Even minor disruptions in the gas feed as a result of internal blockages can transform your lawn mulching beast right into a wheezing mess.

It takes some pretty invasive sleuthing to determine a blocked gas tank or line, so I would certainly recommend consulting a professional and paying them to do it for you.

Wait, Wait, Wait … Professionals? This Is Starting to Sound Expensive

I know you’re probably bracing your savings account for a severe hit, yet if your mower is covered by a guarantee, you may have the ability to obtain the supplier to repair it for you for totally free– hooray!

Some businesses will even send out an engineer to your door to either fix the mower right then and there, analyze the issue and order parts, or accumulate it for fixings at a business solution depot. You will not need to raise a finger!

If your guarantee has actually expired, or you never had one to start with, it’s best to look for a tiny, reliable service centers in your area. These small clothing are usually staffed with extremely seasoned employees, and the prices are far much less frightening than you could visualize.

Lawn Mower Maintenance: Prevention Is Better Than the Cure

Before we go our different ways, I believed it ‘d be an excellent idea to go over some professional lawn mower upkeep pointers, as the best means to ensure you’re never stuck to this problem once more is to take good treatment of your machine.

Preventative Lawn Mower Maintenance

  1. Tidy your air filter — It’s a common method to clean a mower ‘s air filter once every 25 running hrs, so if it takes you 2 hours to cut your lawn’s, it ought to be provided great twice every 12 1/2 mows.
  2. Replace your air filter — I replace my air filter when annually, however if you have quite a great deal of ground to cover, and also you strike 300 running hrs prior to the new year, don’t be reluctant to switch it out earlier than scheduled.
  3. Tidy your carbohydrate — It’s generally recommended that you clean your carbohydrate around three times a year. I provide for mine some TLC when a period, excluding wintertime.
  4. Support your gas — Unless you’re taking the TriFuel route (a sensible choice), make sure to mix your gas with a fuel stabilizer, especially before putting your lawn mower right into storage for the wintertime.
  5. Degrease as well as tidy your engine — If you’re usually up versus lengthy or damp grass, you ought to decrease as well as clean your lawn mower motor when a season, but, most of the times, twice a year is plenty.
  6. Attempt not to overfill your oil reservoir — Remember, your dipstick is your best buddy!
  7. Replace your stimulate connects — As long as you keep them tidy, your spark plugs ought to last for 2 years.
  8. Locate appropriate storage — Your mower requirements to be kept in a dry area, secured from the climate, but if you have nothing else option however to maintain it outside, be certain to raise it as well as cover it with a sturdy tarp.


Which brings us throughout of my mower guide. If you’re still below reviewing this, thank you for your time, yet a part of me hopes you never also made it this far.

With any type of luck, one of the solutions discussed earlier will have resolved your concerns, as well as you’re currently active cleaning up your backyard before your fussy neighbor, Val, catches a glance and crosses you off her Christmas card checklist.

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Mutasim Sweileh

Mutasim is a published author and software engineer and agriculture expert from the US. To date, he has helped thousands of people make their yards lush and thick.