Lawn mower shaft replacement. How To Replace Lawn Mower Oil Seal (Beginners Guide With Pictures)

How To Replace Lawn Mower Oil Seal (Beginners Guide With Pictures)

An oil leak can be annoying, but far more annoying is running low on oil and destroying an otherwise perfect mower. Most people would likely just keep topping up the oil, so I’m genuinely impressed that you’re taking the time to fit an oil seal.

How to replace a mower oil seal? To fit a lawnmower crankshaft oil seal, begin by draining the engine oil, then:

• Remove the engine
• Using a drill, screw and pliers remove the old seal
• Using a soft faced hammer, fit the new seal
• Refit the engine
• Fill with fresh oil

Oil Level – Just before replacing the crankshaft oil seal, it might be worth considering the oil level, is it too full?

Excessive oil will increase crankcase pressure, which causes seals to leak. Often removing the excess oil stops the leak.

A faulty carburetor float needle is a common cause of a persistently high oil level.

Common Engine Oil Leaks

Some oil leaks can be tricky to diagnose. As a mechanic over the years, I’ve learned not to jump to conclusions, it can lead to unnecessary expense, labor not to mention your pride. It’s better to run a simple test to confirm your suspicions. Mower engines commonly leak oil from a few different locations, and as gravity causes the oil to run south, the lower crankshaft oil seal usually gets the blame.

The crankshaft has an upper/front crank seal also but doesn’t usually cause problems. Let’s take a quick look at where the other common oil leaks are and how we can quickly diagnose the source.

• Dipstick O-ring seal
• Valve cover gasket
• Crankcase breather
• Cylinder head-gasket
• Oil filter leak
• Oil pan gasket
• Oil drain bung

Seals – A bad dipstick seal or oil drain bung will cause engine oil leaks.

Too Much Engine Oil

By far, the most common cause of lawnmower engine oil leaks is too much oil. When the oil level is too full it causes excessive back pressure inside the engine. The pressure forces the engine oil to escape from areas such as the dipstick seal, lower crankshaft seal, oil pan gasket and can cause the head gasket to blow on push-rod OHV engines.

Oil level check is a simple check and an easy fix – too much oil means you likely found your problem. In most cases simply draining off the excess oil will cause the oil leak to stop.

Diagnosing An Engine Oil Leak

You already know, any engine oil leak will migrate south, which can cause us to blame the crankshaft seal. While we may be right, crank seals cause lots of oil leaks. But it’s worth taking a few minutes to check a fact is a fact.

• Turn the mower over (carburetor side facing up – prevents oil spill).
• Clean the crankshaft seal and the engine pan thoroughly using a de-greaser or brake cleaner. You’ll likely have oil on the deck underside as the spinning blade distributes a coat, but don’t concern yourself, it won’t do any harm, it helps preserve the metal.
• Turn the mower onto four wheels again and clean any oil trace from the top side of the engine.
• Check and top up oil if necessary and simply go cut some grass.
• After about ten minutes running, the engine oil gets hot which causes it to thin. This is usually when a leak occurs.
• Allow the engine to cool before turning it over (carburetor side up) and check for oil leak at or around the seal.
• No oil at the seal means the seal is good.
• Now go ahead and check the upper side of the engine for an oil weep.
• Until you find the source, replacing seals isn’t advised.

complex mowers may have more than one oil type in close proximity to the engine, such as hydraulic power-assisted steering, etc. In these cases identifying an oil, a leak can add a few extra layers of complexity. The solution – add an oil dye to whichever system you suspect is leaking, clean, and inspect after the operation as before.

Leaks – A little detective work will confirm the source.

Tools

I use an oil seal puller to remove the seal but you don’t necessarily need one. You’ll need to remove the engine from a tractor mower and just the blade and blade boss from a walk-behind mower. The tools required for this are basic, selection of wrenches and sockets. An impact gun makes the whole job a ton easier, check out the Amazon link below.

The tools and supplies you’ll need to fit a crankshaft seal include:

• Engine de-greaser
• Oil drain
• Adjustable wrench
• Drill
• Wood screw
• Vice-grips
• Large socket or soft faced hammer
• Engine oil

An oil seal puller would be nice but not essential.

Replacing Mower Crank Seal

Replacing a lawn mower crankshaft seal isn’t that difficult. However, a walk-behind mower is easier than a tractor. The walk-behind mower will require the removal of the blade, blade boss, plastic shroud, and drive pulley (if fitted) from the crankshaft in order to gain access to the oil seal. The tractor mower will require a cutting deck, drive pulley, and engine removal.

Crankshafts usually have a buildup of grass and corrosion, so cleaning them thoroughly with a wire brush and lots of WD40 will help when it comes to removing the drive pulley, especially on walk-behind mowers. An impact gun does make life easier when it comes to removing walk-behind mower blade bolts and is very useful on tractor mower clutch assemblies /PTOs.

Note of caution, when removing the old seal, you’ll need to be very careful not to damage the sealing surfaces of the crankshaft and oil pan. Using a screwdriver to gouge or pry will damage the metal and the new seal will leak.

Steps To Remove Lawnmower Crank Seal:

Gain Access – Drain the engine oil to begin and pull your walk behind the mower spark plug wire (prevents mower starting). Always turn to walk behind mower over with carburetor side facing up – prevents oil spill and starting issues.

Fitting a walk-behind mower seal – remove blade and boss. Need help, check out the “Blade fitting video”.

Tractor – Engine out.

Pic – Note how the seal seats, this will be valuable info to you later when driving home the new seal.

Drill – An oil seal puller is the right job, but you might not have, instead carefully drill into the center of the seal, it helps start the screw.

Fit screw – A rough thread screw is perfect for removing the seal, use two, one on each side if you prefer.

Vice Grips – What would the world look like without the trusty vice-grips.

Ease it out – Having a screw on either side and two vice-grips will give you greater control when removing.

Gently does it – Remove it with care, rough play will mark engine seal surfaces, and that will cause an oil leak that can’t be fixed easily.

Steps To Fit Mower Crankshaft Seal

Most seals are fitted using a wipe of engine oil to help fitting and sealing, however, some seals need to be fitted dry, so consult with your part supplier first. The mating surfaces need to be clean and free from dirt but do not use anything metal to clean the surfaces, likewise do not use sandpaper. If you require an abrasive, use the scouring face of a household sponge.

I use a deep socket to drive the seal in this guide, you may not have one. Instead use a suitable size piece of timber and hammer, plastic plumbing pipe cut to size makes a useful driver, or use a rubber hammer. The seal must be driven home square, gently tapping uniformly all the way around the seal will seat it correctly.

Clean lube – With the sealing surfaces clean, lube your seal if applicable.

Gently – Start the seal by tapping it gently, one side and then the other.

Drive – I’m using a deep socket to drive the seal. This is the preferred way as it drives the seal squarely.

Home – Use your reference marks or picture you took earlier to note where the seal seats are. Over egging the seal will damage it.

That’s it, you did it, Nice work! Now refit the engine and not forgetting to refill the oil.

Related Questions

Why is my lawnmower leaking oil? The most common cause of lawn mower oil leaks is an overfilled crankcase. Draining off the excess oil will often fix the leak.

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If you’re looking for the engine number, that can be found directly on the engine itself.

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The John Deere Easy Change™ 30-Second Oil Change System

Never drain engine oil again.

We’ve changed the oil change. Revolutionized it really. See how fast and easy changing your oil can now be on 100 Series Riding Lawn Tractors with the John Deere Easy Change™ 30-Second Oil Change System. Only from John Deere. Included on the E120, E130, E150, E160, E170, and E180 models.

Step One. Take it off.

Lift the hood. Make sure the engine is cool, then, twist to remove. It’s that simple.

Step Two. Twist and lock.

Grab the new Easy Change™ Canister, twist and lock into place. Make sure the arrow on your Filter System aligns with the arrow on your engine.

Step three. Done.

Close the hood and mow. John Deere recommends the Easy Change™ 30-second Oil Change System every 50 hours or at the end of your mowing season. Don’t drain engine oil ever again.

Draining engine oil is so 2017.

The engine modifications and new technologies are in. The re-envisioned oil filter with a media designed to resist breaking down in oil over time is here. The thousands of hours of testing are done. The end result is an all-in-one, oil and oil filter system like no other. The first of its kind. And thanks to the new John Deere Easy Change™ 30-Second Oil Change System (“System”), you’ll never have to drain the oil from 100 Series Riding Lawn Tractors again.

Here’s why: The new System captures contaminants and recharges your engine with nearly a quart (0.8qt) (0.76 l) of new oil. In fact, this System increases the amount of oil in the engine by nearly 40%. 2 Your engine likes that.

What do you mean, I will never have to drain oil from my engine again? How is that possible? The answer is simple. We have developed a better filtration system and filter design for our 100 Series Riding Lawn Tractors 1. This fully synthetic filter media has greater surface area which increases its capacity to hold harmful contaminants. What’s more, the filter media is designed to resist breaking down in oil over time. Which means you’ll get a cooler running engine. And a cooler running engine and better filtering helps increase engine oil life. John Deere’s recommended oil service for 100 Series Riding Lawn Tractors 1. is to change the System every 50 hours or once a season, whichever comes first. Remember, the System replaces a portion of your engine oil. And that’s plenty.

The System uses John Deere Turf-Gard™ Oil. Using John Deere Turf-Gard™ Oil ensures you are using the exact oil specified by John Deere engineers.

Testing. Testing. Testing. Thanks to thousands of hours of rigorous and extensive testing, you can feel confident your engine will run for years to come.

1 The John Deere Easy Change™ 30-Second Oil Change System is available on E120, E130, E150, E160, E170 and E180 Lawn Tractors today.

2 Compared to similar V-Twin engine models that do not have the John Deere Easy Change™ 30-Second Oil Change System. That includes equivalent Deere 2017 models and 2018 models without the System.

Frequently Asked Questions:

What is new with John Deere Riding Lawn Equipment?

We are excited about the exclusive John Deere Easy Change™ 30 second oil change system. Exclusive to John Deere and only available on certain models of the new 100 Series Lawn Tractors. These tractors are designed for ease of use for both operation and maintenance. The John Deere Easy Change™ System (“Easy Change”) allows the user to easily complete the recommended engine oil and filter maintenance in 30 seconds.

What is this new oil change system?

We changed the oil change. The all-in-one oil and oil filter system gives the owner the ability to change a portion of the oil and the filter in less than 30 seconds.

What happens to the rest of the oil in the engine when the Easy Change system is replaced?

The Easy Change system replaces.8 quart of oil. The remaining oil in the engine is refreshed by the charge of new oil included in the replacement Easy Change system. Combined with 40% more engine oil capacity, improved filtration and cooler running temperatures which help extend oil life, it is no longer necessary to remove and dispose of all the oil in your engine during service.

What makes the Easy Change system unique from other filters?

It is not just a filter. It is a newly developed technology system that allows a new “filter” to come already charged with oil and allows you to remove an existing filter and the contaminants inside without tools and without making a mess. Beyond the filter, technology within the canister and on your engine makes this possible.

Models with the Easy Change oil system use a fully synthetic filter that has more capacity to trap and hold contaminants. The larger surface area of the Easy Change canister acts like a radiator helping the oil to stay cool.

Does the Easy Change system somehow decrease the life of the engine?

The John Deere 100 Series lawn tractor models, with and without Easy Change, are specified for the same lifetime and are rigorously tested to the same standards to ensure the life of the tractor meets expectations.

Can I add the Easy change system to an existing tractor?

Because this system also requires unique features within the engine, the Easy Change system cannot be added to an engine that was not equipped with it at the factory.

Can I change all the oil if I choose to?

You could if you wanted to. There is an oil drain plug. It is not required for maintenance.

How often do I need to change the Easy Change canister?

Every 50 hours or once a year. The 100 Series Lawn Tractors with and without the Easy Change system have the same maintenance schedule.

What type of oil is recommended?

We recommend only John Deere Turf-Gard™ 10W30 Oil. The Easy Change canister comes pre-filled with John Deere Turf-Gard™ 10W30 oil.

How do I recycle the old oil?

Many local government recycling programs, authorized retailers, auto repair stations, and auto parts stores will puncture and recycle used oil filters and oil.

Do I ever need to add oil?

Yes. Consistent with our service recommendations for this product, you should check oil level daily and add oil if required.

Introduction: Mower Kicks BackReplace the Flywheel Key

About: I miss the days when magazines like Popular Mechanics had all sorts of DIY projects for making and repairing just about everything. I am enjoying posting things I have learned and done since I got my first to… About Phil B »

Your mower does not start. Sometimes it fires weakly, but yanks the starter cord from your hand.

Your flywheel key is sheared and it needs to be replaced. The flywheel moved and sheared the key. Now the engine timing is very much incorrect. The spark comes at a time that makes the engine want to run backwards, but it cannot.

As a safety precaution, always remove the spark plug wire before working on a small engine.

Step 1: Why?

The flywheel key shears to protect the crankshaft from twisting, which would cause a very expensive repair. A soft key allows the flywheel to move on the crankshaft when your mower blade hits a tree root, an old stump, a large dried clod of dirt, etc. If the mower blade is loose, that will cause enough shock to shear the flywheel key, too.

Pictured is a repair I made to the blade holder. It had two raised tips to fit the blade slot. Those had become battered and the blade had some looseness, no matter how tight the center bolt was. I drilled out the tips and replaced them with hardened bolts. (Because of space limitations, I had to grind one side of each bolthead away at the top of the blade holder. This blade is actually a thatching blade. Somehow it is causing flywheel keys to shear. I think I will no longer use a thatching blade on this mower.)

Step 2: A New Key

Although sold by Sears, my mower engine is made by Tecumseh. There are several flywheel keys used on Tecumseh engines. Even if your mower is sold by Sears, you can take the Sears model number to your local mower shop and they can find the correct key for you. The key shown is part number 611004. It has a wider, thicker portion at one end. That end faces down on my engine. I was assured the key and flywheel would fit only when the key is in the correct position. (The photo is from Google Images.) A new key is about one dollar (US) in cost.

Step 3: Begin

The first step is to remove the gasoline tank. You will need to remove the oil dipstick first and set it aside someplace clean where it will not attract dirt. Set the tank aside, even though connected by its rubber hose. Set it with the cap upward so gasoline will not leak out. Also remove the red cooling shroud.

Step 4: Prepare to Loosen the Flywheel

Most people will not have a factory issue flywheel puller in their toolbox. You do not need one, if you are careful. Remove the starter rope cup and put the nut back onto the threaded portion of the crankshaft. Turn it until the face of the nut is exactly flush with the top of the crankshaft.

Step 5: Pry and Tap Sharply

Use a long screwdriver to pry from below the flywheel. Do not pry too hard. You do not want to crack the crankcase. At the same time, tap sharply on the nut. The nut protects the threads. Turn the flywheel a quarter turn after 3 or 4 taps. It will come loose more easily than you would expect. When it breaks loose, remove the nut and lift the flywheel off.

Step 6: Remove the Old Key Fragments

The old key will come out in pieces. Use a finish nail to pry what is left out of its keyway.

Step 7: Insert the New Key

Insert the new key with the wider, thicker end downward. You can see the new key properly installed on the shaft.

In the photo the green spring attaches to the automatic engine brake. Before placing the flywheel back onto the crankshaft, tie the dead man’s clutch lever against the mower handle so it is held as when you are mowing.

Step 8: Install Flywheel

Place the flywheel on the crankshaft. It should slide down smoothly over the new key. Oil the threads on the end of the crankshaft. Place the cup, the washer, and the nut onto the crankshaft. Begin to tighten. Never pry against the flywheel cooling fins. They break easily. Turn the flywheel a couple of times to make certain it turns smoothly and nothing is obstructing it. If you did not tie back the dead man’s clutch, you will hear a terrible scraping sound. Torque the flywheel nut. The recommended specifications are usually around 33 foot pounds. On some engines the figure will be 35 or 39 foot pounds. In general, if you are shearing a lot of flywheel keys for no reason, the nut is not yet tight enough.

Step 9: Top Off the Oil

When turning the engine while the oil fill is open you are certain to have some oil belch out of the engine. Top off the engine with new oil. Usually you fill to the level of the opening.

When you place the cooling shroud back onto the engine, you will guide the oil fill tube back into the fill hole on the engine. There is a rubber gasket that goes around the fill tube. It is easy for this to become separated from the fill tube during removal. Be sure this gasket is in place before you finish.

When all of the shrouds are back in place, untie the dead man’s clutch and put the spark plug wire back onto the spark plug. Check the oil just to be safe. Push the primer bulb three times. Grab the dead man’s clutch and pull the rope. The engine should start on the first pull of the rope.

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Комментарии и мнения владельцев

I installed a new flywheel key sold to me by local Ace Hardware for mower with Briggs Stratton engine. Put mower back together. Pull rope would not pull out. When I took that part off again, I inspected and it is not cracked that I can see and pulls out nicely. The key seems a hair bigger than the one I could get at Amazon that is specificly for this mower engine. Ace said this would work. the key causes it to be just slightly off center. I’ve attached a picture. What do you think?

Hi I had a question since I am not really that mechanical with engines. My JS40 Walk behind mower was running ok and then all of a sudden I went to start it and the pull chord just locks up and will not turn the flywheel. First I thougt it was a spark plug so I replaced it. nothing. Then I seen it could be a flywheel key and I removed it and it looks perfectly fine? Any advise? Because the chord is still working off the engine but so hard to pull and make the flywheel move?

If you take the spark plug out, can you turn the engine by means of the mower’s blade, or is it very difficult to turn? (Do not turn the engine with your hand on the blade underneath unless you have removed the spark plug. You do not want it to start accidentally with your hand under the mower.) If you remove the plastic oil fill tube, is there oil up to the top of the engine casting where the plastic fill tube fits into the hole on the metal crankcase casting, or can you barely see any oil? I am wondering if the engine was run without enough oil and the rings may have seized in the cylinder. You can try putting a spoonful of oil in the spark plug hole and slowly turning the engine slowly in a clockwise direction to see if it loosens up. (I once ran a small 2-cycle engine with a gas oil mixture that was too old. After a few minutes the engine rings seized. I thought I had ruined the engine, but a little oil in the spark plug hole after letting it cool and slowly turning it with a long wrench brought it back.) it will probably be best if you keep the mower level so oil does not flow into parts of the engine where it does not belong,

I hit a rock in my yard and my Briggs and Stratton mower stopped running. It sounded like the most common issue with this would be the fly wheel key. I took mower apart and replaced the fly wheel key and tried to start the mower. The mower started but with low power and only lasted about 30 seconds. I then did this all over again with the same results. This time I heard a bit of rattling before it died. Any suggestions on what this might be?

The flywheel key is supposed to prevent damage to the crankshaft by absorbing the sudden deceleration and shearing. If and when it does not, there is the possibility the crankshaft bent. Remove the spark plug and set the mower up on its side, the side that does not allow the oil to get into everything. Look at the crankshaft closely as you turn the blade. Is there any wobble? There are ways to straighten a crankshaft. It might be time for a different crankshaft from a donor engine, or a different engine.

I have lawn mower Craftsman model # 917.377823. I am having problem to fix it. flywheel key has been sheared. I did replace key on new one. After I was able to start engine for testing, after running engine about 2 minutes I turned off engine, but after I could not start it back. After dissembling I realized it sheared key again. Any advice about this problem will be appreciated.

I ran into the same problem. I found the torque specifications for the crankshaft nut on my engine. I believe it was around 30 or 35 foot pounds. That was just the minimal amount needed to keep the flywheel from shearing the key again. would have helped, but I am cautious about torquing more than specified.

Phil B,I just took apart my lawn mower, replaced the key, put it back together and she runs like new!

2 hours, including improvising a jig for my bearing puller and a trip to the hardware store for a new key. Next time I could do it in 30 minutes.

Bill, Welcome to Instructables. I am glad you found my Instructable and that it solved your problem. I hope you enjoy Instructables. I am eager to see anything you might want to publish here. Once I had a situation that caused our mower to shear the flywheel key often. I eventually made timing marks on the engine shrouds so I could check the timing before the work of tearing into the engine. Here is the AC powered timing light I made.

My BS mower stopped working after running over a small piece of styrofoam. Initially, it would sputter for about 10 seconds before dying. Now it does that the first try, and nothing after that. I’m not much of a repair guy, but I’ve checked the carb, gas line, replaced filter, spark plug, gas oil, cleaned everything out with compressed air. Thought it might be the flywheel key, but couldn’t get the 15/16˝ nut that covers it off, even with PB Blaster and a blowtorch. Starting to think I should bite the bullet and take it to a repair shop, but worried about the cost. Anything I missed?

Please add to the checklist below a look for loose screws or hardened gaskets that do not allow the carburetor body to seal completely against the intake mount on the engine block. This is something that you cannot detect visually, but any screw even a quarter of a turn loose can allow air to leak into the gas/air mixture. That makes the mixture extra lean and lessens the engine’s ability to draw fuel into the combustion chamber. If gaskets are ten or so years old, they are probably too hard to seal well. You can get some gasket material and cut your own gaskets using the old gasket or the flange on the carburetor as a guide.

I’ve checked many of these things already. I need to check compression and the carburetor diaphragm. it could very easily be one of those. Thanks a lot for the thorough check list!

The symptoms you describe seem to be consistent with an engine timing problem caused by a sheared or partially sheared flywheel key. I have always been able to remove the flywheel nut on the crankshaft with a long wrench handle and the blade as levers to work against one another. That must have been some piece of Styrofoam.

I usually go through a process of steps when checking a small engine to discover why it will not run. You may have already covered these. Be sure to look at the final paragraph marked IMPORTANT. It is crucial on certain popular B S engines.

Fuel flows into the carburetor float bowl freely?

No dirt obstructing the idle mixture screw valve?

Clean air filter? (Test by removing the air filter and starting the engine. Air filters can appear clean to the eye, but are not.)

Adequate compression? (If you have a compression tester, you need 60 psi at minimum. Or, if you spin the top of the flywheel clockwise rapidly by hand, it should bounce back in the reverse direction on the compression stroke, not just stop and wheeze a little.)

Clean, new spark plug? (Spark plugs can appear clean, but degrade with age so that they do not fire under the pressure of the compression stroke.)

A good blue spark when the engine is cranked? (Remove the spark plug from the engine, but leave it attached to the plug wire. Wrap some bare copper wire around the threads and fasten the wire to the engine frame for a good ground. Deactivate any dead man clutch that cuts the spark out. Spin the mower engine and look for a blue spark. The fatter the spark, the better.)

Engine timing? (This is the matter addressed in this Instructable. It is necessary to remove the nut and washer holding the flywheel on the crankshaft and seeing if the keyways in both the flywheel and the crankshaft align exactly.

IMPORTANTMany vertical shaft B S engines use a rubber diaphragm in the carburetor. This diaphragm is about 2.5 x 3.5 inches in size (just guessing from memory) and it has a stiff wire fastened to its center. After 5 or 6 years these diaphragms stretch and do not pulse properly any longer so that the choke plate is not controlled properly in the carburetor. Unscrew the top half of the carburetor after removing the air filter and replace the diaphragm if the mower is more than 5 years old. There is no way to tell visually that this diaphragm is defective, but replacing it makes a big change in the way the engine starts.

I think one of these checklist items should help you find the problem.

When to Replace a Lawn Mower vs. Repairing One?

A carbon-coated spark plug can make for hard starting, and so can old gas or a plugged carburetor. All are easy to fix.

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It’s not uncommon to see “broken” lawn mowers getting sent to the scrap heap. For too many people, a mower that won’t start, and needs more than gasoline or fresh batteries, is easy to cast aside. But the reality is most of the repairs a broken lawn mower requires are relatively minor, easy enough to fix yourself and much cheaper than spending hundreds or even thousands of dollars on a new model.

What’s Wrong with Your Lawn Mower?

Plenty of lawn mower problems are relatively minor issues that you can fix yourself. A carbon-coated spark plug can make for hard starting, and so can old gas or a plugged carburetor. Both are easy to fix. The same with replacing broken cables, belts or pull cords—easy enough to fix with a few parts and a little know-how

Other times, a lawn mower has more serious problems that might be prohibitively expensive to fix, if they can be fixed at all. A malfunctioning mower might be the result of a bent shaft caused by hitting a rock or other debris. You might also experience a cracked body from the mower being dropped, or more serious internal engine problems that could require a replacement.

If your lawn mower won’t start, there’s a checklist of things you should go through to figure out what’s wrong with it. That will help you determine whether or not you can fix it yourself.

When Should You Replace a Lawn Mower?

When more substantive problems develop, like the ones mentioned above, is when you have to ask yourself if it’s worth fixing the mower. The decision to pay for repairs versus buying a new machine depends on a few things. Is your lawn mower old? If it’s more than a decade old, it might be time to think about buying a new lawn mower. Mowers have become more efficient over the years, so there are benefits to buying new.

Another consideration is how expensive was your mower to begin with? If you got used mower on the cheap or a budget pick for less than 200, you might be better off with a new model for any repair bill north of 75.

Riding mowers, of course, are a different story. Because they have a much higher price point—with reliable budget picks often starting in the neighborhood of 1,500—repairs costing several hundred dollars are often worth it. But if your riding mower’s engine needs to be replaced, then it might pay to get a new riding lawn mower rather than sinking any more money into the old one. If you follow a handful of regular riding lawn mower maintenance and repair steps, you can keep your machine running smoothly for a long time.

Buying a New Lawn Mower

With so many different kinds on the market, you need to do a little research before you buy a lawn mower. The main factors are the size and shape of your yard. If you have a postage stamp-sized lot, you can get buy with a basic push mower. For uneven ground or a yard that sits on the side of hill, you’ll want a machine equipped to handle the terrain safely. Big yards, an acre or more, are nice to have, but it can take some time to cut the grass, so it’s worth considering riding mowers to help get the job done faster.

When Is the Best Time to Buy a New Lawn Mower?

As a general rule, the best time to buy a lawn mower is in the spring or fall. In February and March. That’s when retailers will often have deals before demand starts to peak. In the fall, stores are clearing space for other seasonal equipment and getting ready for new models next year, so they’ll often have deals on mowers as the days get shorter and the nights get colder.

If you’re in the market for a lawn mower, start by researching what kind of machine as well as the mower brand and model you want. Then, keep an eye out for sales and deals.

Lawn Mower Maintenance Tasks That You Can DIY

Sometimes an ounce of prevention is worth a pound of cure, so experts recommend a few things to keep your lawn mower running well. Here’s a complete lawn mower maintenance checklist.

Change the Air Filter

A clean air filter helps maintain the proper fuel/air ratio, allowing the mower to burn less gas. Changing the air filter is easy, just check the manual (or look on the manufacturer’s website) to determine which one you need for your machine. It’s easy to replace an air filter too, and won’t cost much, so if it’s really filthy, it might be best just to get a new one.

Check the Spark Plug

Spark plugs ignite the fuel and air mixture inside the engine. When spark plugs start to fail or get dirty, your engine will sputter, and it might not even work. Give the spark plug a look before you roll out the mower for the first cut of the season. Check for carbon buildup. You can clean it, or you may need to replace the spark plug, which is relatively easy to do and only costs about 5.

Sharpen Your Lawn Mower Blade

Dull blades don’t cut very well. importantly, a sharp blade is better for the health of your lawn, giving the grass a clean cut that helps the plants recover quickly. Another benefit of a sharp blade is that it will reduce the time you spend mowing. For best results, sharpen you lawn mower blade twice a year. The Sharpal Knife Sharpener is a brilliant tool that gets the job done quickly and easily.

Change the Oil in Your Lawn Mower

Changing your lawn mower’s oil will help keep it running efficiently, and help the machine last longer. You should change the oil in your mower once per season. A lot of people opt to do it at the end of the season, when it’s time to winterize the lawn mower.

Add a Fuel Stabilizer to Your Lawn Mower

One of the most essential steps for winterizing a lawn mower is to add a fuel stabilizer at the end of the mowing season. that will help to keep the gas from going bad and causing issues with starting. Another option is just to drain the gas out of the mower entirely.