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Lawn & Garden Tips – Spring Lawn Mower Tune Up

De-winterize your lawn mower

After a long, cold winter, the air warms up, the rain starts to fall, and with it comes the greenery. Eventually, you have to drag that mower out of the garage and put it to work. Unless you did the proper winterizing, then you will likely have some work to do getting it up and running. De-winterizing is a the process of changing fluids and components, checking all the vitals and general inspection of the working parts of the equipment. This spring lawn mower tune up can usually be accomplished in an hour or so, but if the equipment has been neglected, as lawn mowers usually are, it can take some time getting it up and running in top shape. Here’s a few quick projects to help get your mowing season started right.

Battery Check

If the equipment has an electric start, then it has a battery. A drained battery can make your lawn care tasks much more frustrating. Use a volt-meter to check the voltage. If it is a 12-volt battery and the voltage is below 11 volts, it probably won’t start. Put the battery on a charger to bring it up to full charge. If it won’t take a charge, then you will likely need a new one. See our lawn & garden battery article for more tips.  Whether you use your existing battery or buy a new one, you should go ahead and clean the battery terminals. Remove the battery from the mower and give each battery terminal a good wire brushing. Be sure to remove all corrosion before bolting everything back together. Give each battery connections a good spray of battery terminal protector.

 

Check your battery first. If there is no juice, you can't get it started. This battery is only registering three volts, that won't do.
Check your battery first. If there is no juice, you can’t get it started. This battery is only registering three volts, that won’t do.

Engine Air Filter Replacement

If your engine can’t breathe, it can’t run. The air filter on lawn & garden equipment should be replaced annually. You may be tempted to just knock the dust off an old filter and toss it back in, but resist that temptation. NAPA Auto Parts Stores have a wide selection of air filters for the most common small engines, you are sure to find the one you need. Many push mowers use a universal filter element made from foam, which is often cut to fit.

 

A clogged up filter will have your engine weezing and choking for air. Replace the filter annually.
A clogged up filter will have your engine wheezing and choking for air. Replace the filter annually.

 

The foam is larger than necessary to fit a wide range of housings. We trimmed this one down to fit our filter box.
The foam is larger than necessary to fit a wide range of housings. We trimmed this one down to fit our filter box.

 

The filter should fit tight, not loose.
The filter should fit tight, not loose.

Engine Oil Change

Probably the single most overlooked aspect of all small engines is the oil. Where a dead battery or clogged filter will show symptoms, the oil in your lawn & garden equipment doesn’t show any issues until it is too late. Most small engines should get fresh oil annually, some more often depending on the use and the type of equipment it is. Changing oil at the start of the season is a good habit that can help extend the life of your equipment. Most small engines have a small plug at the bottom of the engine block for easy draining. Don’t forget the filter (if it has one).

Don't neglect your oil! Check it every time you mow and change it every 50 hours of use.
Don’t neglect your oil! Check it every time you mow and change it every 50 hours of use.

 

NAPA synthetic 5W-30 for our Briggs and Stratton engine. Don't forget to change the filter.We used <a href="&quot;https://www.napaonline.com/en/p/NO_75520&quot;" target="&quot;_blank&quot;" rel=

Spark Plug Check

A fouled out spark plug can have you pulling out your hair. Spark plugs can last for years, but it is always a good idea to pull them out annually, check the gap, look for signs of oil fouling, and wear. When replacing the plug, make sure you replace it with the correct plug, match the code on the porcelain to be sure. When in doubt, replace it.

Most engine manufacturers suggest the spark plug should be changed about every 100 hours. You should check the plugs annually for signs of wear and damage.
Most engine manufacturers suggest the spark plug should be changed about every 100 hours. You should check the plugs annually for signs of wear and damage.

Fresh Fuel

Old gas in the tank is never a good thing. Modern fuels are often mixed with ethanol as well, which can absorb water. Unless you drained the tank before putting the mower away for the season, you likely need to address the old fuel. Pouring new fuel on top old gas is not a guaranteed solution either. NAPA sells a pack of testers to check the state if your fuel, if it is bad, it needs to be poured out before firing up your motor. Make sure to check with your local laws for the proper way to dispose of any old or contaminated fuel. Never pour old gas out on the ground or down the drain.

Bad gas can make the engine a lot harder to start. Check it with a test kit. The cotton swab goes into the gas and left to sit for a few minutes.
Bad gas can make the engine a lot harder to start. Check it with a test kit. The cotton swab goes into the gas and left to sit for a few minutes.

 

The swab is then checked against the guide to determine if the gas is good or not. This gas is as bad as it gets.
The swab is then checked against the guide to determine if the gas is good or not. This gas is as bad as it gets.

Clean Carburetor

Simply cleaning your mower’s carburetor can yield big dividends. Grass clippings and dirt can clump up around the linkage leading to erratic running. Gunk in the gas tank can settle in the bottom of the fuel bowl making for maddening bad or even not running situations. Dropping the bowl at the beginning of the season gives it a clean slate to operate. Give the carb float a good spray down with carb cleaner as well.

Old gas can wreak havoc on a mower’s carburetor, especially if you let it sit in your gas tank all winter. We found a 2-year old push mower on Craigslist that the previous owner said would not stay running. Once we had it home we took it apart to find the problem. As soon as we took the carburetor off, it became apparent that the tank had been left with ethanol gas, which had corroded the aluminum, leaving a bunch of crusty gunk inside the carburetor.

The carburetor is mounted to the fuel tank on this model. It is easily removed.
The carburetor is mounted to the fuel tank on this model. It is easily removed.

We spent a couple of hours cleaning out the carburetor (these are incredibly simple carburetors), bolted it back together and now it runs like a champ. Spending $20 for a practically new mower beats spending $250 for a new one any day.

A lot of build up from the ethanol fuel had accumulated inside the carb.
A lot of build up from the ethanol fuel had accumulated inside the carb.

 

Most of the crud was removed by spraying it with some carb cleaner.
Most of the crud was removed by spraying it with some carb cleaner.

 

We also sprayed the carb itself.
We also sprayed the carb itself for good measure.

Ready to Mow!

While it may seem like a lot of work, a mower tune up usually only takes a short time and it will definitely save you more time down the road. That way you can enjoy your manicured lawn more often without the hassle of servicing your lawn equipment every weekend.

Check out all the lawn and garden products available on NAPA Online or trust one of our 17,000 NAPA AutoCare locations for routine automobile maintenance and repairs. For more information on doing your own lawn mower tune up, chat with a knowledgeable expert at your local NAPA AUTO PARTS store.

 

Jefferson Bryant View All

A life-long gearhead, Jefferson Bryant spends more time in the shop than anywhere else. His career began in the car audio industry as a shop manager, eventually working his way into a position at Rockford Fosgate as a product designer. In 2003, he began writing tech articles for magazines, and has been working as an automotive journalist ever since. His work has been featured in Car Craft, Hot Rod, Rod & Custom, Truckin’, Mopar Muscle, and many more. Jefferson has also written 4 books and produced countless videos. Jefferson operates Red Dirt Rodz, his personal garage studio, where all of his magazine articles and tech videos are produced.

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