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With Winter behind us and the growing season starting, it’s time to get the mower, trimmer, and blower ready to keep the yard clean. Here’s a checklist of the things I do at the start of each Spring to get my mower in tip-top shape.

The mower is the workhorse of maintaining the vast majority of the lawn. Spring prep consists of:

• Change the fuel filter
• Check, clean, and gap the spark plug
• Check and (maybe) replace the air filter
• Change the oil (and filter if it takes one)
• Sharpen and balance the blades
• Check tire pressure
• Level the mowing deck

Change the Fuel Filter

My mower has a inline fuel filter, held in place by the clamps that secure the fuel line to both ends of the filter. Use a fuel line clamp on the fuel-tank side by setting the clamp bar and anvil over the hose and screwing down the clamp to prevent flow of fuel. If you don’t have a fuel line clamp, you can use a vise grip, loosened a little to not damage the hose but still prevent flow. Once that’s on, pull the hoses off both ends of the filter. If there is a small hose clamp on either end, grab a pair of pliers and squeeze the tips together to loosen then slide the clamp away from the fuel filter.

To install the new one, you just have to kind-of reverse the process. Insert the end of the fuel filter into one of the hoses, making sure the arrow points toward the engine (away from the tank). After inserting the filter in both hoses so the hose is up against the filter housing, squeeze the clamps to loosen. Slide the clamps toward the filter until they are over the barb, but there is still a little hose exposed between the clamp and the body of the filter. Tighten the clamps and you’re all set.

The Spark Plug

The spark plug needs a proper gap between the two electrodes in order to provide the spark that ignites the fuel. You;ll need a few more tools for this task. Deep well socket (preferably with a spark plug insert), wire brush, feeler gauge(s) of the needed thickness, needlenose pliers. Remove the wire, then remove the plug with a deep well socket. Once it’s out, take a look at it. It will be a little dirty, but should be intact. Look at the threads and the condition of the electrodes. If they look damaged, or if the porcelain is broken, replace the spark plug. If not, clean the threads and electrodes with a wire brush. Check the required gap in the manual and use the feeler gauges to see if the gap between the electrodes is proper. The feeler gauge should just barely fit in between the electrodes. If it’s too loose, use the needlenose to bend the ground electrode toward the center one. If it’s too close, bend it away. Once the gap is correct, make sure the ground is directly over the anode. Screw the spark plug back into the engine, then reattach the wire.

Air Filter

The air filter is easy compared to the spark plug. Simply remove the air filter, look between the pleats, and tap the filter on the bench to knock out any grit. Reinstall the filter if it’s in good condition or install a new one.

Change the Oil

Oil in a typical lawn mower engine (where you don’t mix the fuel and oil together) serves two purposes: 1) lubricating the metal parts inside the engine where they rub against each other and 2) assisting with cooling the engine. As it wears, it changes color from a clear amber-brown color toward black. It will accumulate some very fine shavings from the parts it’s lubricating as well. The shavings and wear make it necessary to change the oil periodically. My mower, for example, should have the oil changed about every 10 operating hours. For me, that’s about 5-6 mowings since they take about 2 hours each.

You’ll need a few things to change the oil:

• A container to catch the spent oil (the oil capacity for my mower is 20 ounces, so an old OxiClean container works for me)
• An adjustable wrench to remove and reinstall the drain plug
• Replacement oil (consult your mower’s manual for the correct viscosity – mine is SAE 30, and I think most mowers are)
• A couple of rags to wipe away oil drips

If your mower has an oil filter (mine doesn’t – weird, right? Maybe that’s why I have to change the oil so often), you’ll need a couple of other things:

• Oil filter wrench
• Replacement oil filter (consult your manual here, too – oil filters vary widely)

To change the oil, simply line up the catch basin under the mower where the draining oil will run into it. I almost always miss – that’s why I have the rags. Unscrew the drain plug (located near the bottom of the engine – mine is on the right side) and let ‘er rip. I remove the dipstick from the top of the engine as well to provide some air to reduce/prevent “glugging” as the oil drains. Once the oil is all drained out, I wipe up around the drain hole with a rag and reinsert the plug. Don’t overtighten it – it will make the job that much harder next time.

Change the Oil Filter (if you have one)

If your engine takes an oil filter, this is the time to change it. Simply loosen it with the oil filter wrench (or your hand if you’re that strong) and unscrew to remove. Turn it upside-down over the catch basin to drain the spent oil out of it, then wipe all oil off the engine where the filter mounts. Make sure the flat surface around where the filter screws on is nice and clean! Any grit or pieces of old filter seal left on the surface will cause the new one to not seal properly.

Installing the new filter is pretty easy, too. Get a few drops of fresh oil on your finger and moisten the rubber seal on the filter, then screw it on where you removed the old one. Once the seal makes contact with the engine, tighten only another quarter- or half-turn.

Adding Oil

Now that the filter is replaced (if your engine has a filter), you can add oil again. Borrow a measuring cup from the kitchen (OK – steal it – you won’t want to use it for food anymore, anyway – but buy a new one for the kitchen before you’re caught) and measure out the amount of oil prescribed in the mower’s owner’s manual. Pour it in through the place where the dipstick is usually inserted (you may want to use a funnel for this). Once it’s all poured in, reinsert the dipstick and leave it a few minutes. Check the oil level as you usually would and top off, if needed. My mower manual says 20 ounces, but I end up putting in about 24 to get the dipstick to read above “add more.” Check the filter (again, if you have one) and the drain plug for leaks. If they’re not leaking, you’re finished! You just need to figure out what to do with the spent oil. Most localities frown on throwing it in the garbage or just pouring it out on the ground. A lot of car-care places, though, will take it (think auto parts stores, mechanic shops). Sometimes they charge a little to dispose of it for you. I’ve read where some people burn spent motor oil to heat their shops in the winter.

Sharpen and Balance Mowing Blades

Sharp, balanced mower blades make the mowing job faster and more pleasant. Faster because the sharp blades cut more efficiently; more pleasant because balanced blades don’t wobble – wobbling adds more vibration to the process, which is not pleasant. There are as many ways to sharpen mower blades as there are people to do it. I approach it simply, with an angle grinder and a balancing tool, although you can usually get the balancing tool in a kit with a sharpening stone that fits your drill.

Sharpening

I start by cleaning any residue off the blades with a brush. Sometimes cut grass sticks to the underside of the blades, as does other junk. This junk will affect the balance of the blade later, so I clean it off before I start.

Once the blades are clean, I go after them with the angle grinder very lightly. If the blade is nicked, I start by grinding perpendicular to the bottom of the blade to work the nicks out. Once the edge is straight, I start on the top (beveled) part, again taking very light passes. I follow the already existing angle with the grinder to preserve the cutting angle, and work the front edge down from blunt to a sharp edge. Once one side is finished, I do the same with the other.

You can do the same thing with the grinding stone – use the plastic ring as a guide along the bottom of the blade and the stone to grind away at the beveled edge.

Regardless of the method: grinder, file, or stone, don’t try to sharpen any farther along the length of the blade than was done at the factory. The blade isn’t designed to cut any closer to the center spindle than that.

Balancing

Now, to balance. Don’t try to balance the blade until both cutting edges have been sharpened and any grit, etc. removed. Otherwise, you will be making the blade off-balance. Set the blade on the balancer, centering the balancer in the hole where the blade attaches to the spindle. One end of the blade will probably be low (heavier) than the other. Simply take the blade off the balancer and grind a little off the end of the blade (not the edge!). Place it back on the balancer and repeat the process until the blade is balanced (very close to) level from end to end. Eyeballing it is fine. Once all blades that need to be installed (my mower has 2) are sharp and balanced, you can reinstall them in the mower.

Tire Pressure

If your mower has solid tires, you can skip this. If not, please read on:

Appropriate tire pressure affects a few parts of mowing, much like driving: riding comfort, grip on the ground (without excessive slipping), and mowing deck leveling. If the tire pressure is low, the mowing deck can’t be leveled correctly, leading to weird patterns in your lawn.

With a tire gauge, check the pressure. I always rotate the tires so the valve stem is in the upper half as it’s standing on the ground. This is because I keep slime in my tires all the time to prevent losing pressure due to punctures. For my mower, the front tires are supposed to be at 15 PSI, rear at 10 PSI – as always, consult your mower’s owner’s manual. If the pressure is high, let a little air out. If low, add some air. Repeat until your tires are at the correct pressure.

Level the Mowing Deck

Most (if not all) riding mowers have adjustable mowing decks to correct for wear over time. Consult your owner’s manual for specific procedures. Here’s the process for my mower:

• Park the mower on a level surface, such as a garage floor
• Set the mowing height adjustment to the middle setting (3 out of 5)
• Turn the blade by hand so it is pointing forward and back under the mower.
• Measure the distance from the floor to the forward tip of the blade and from the floor to the rear tip of the blade. If they are more than 3/8 inch apart, adjust the forward adjustment bar until they are 3/8 inch apart.
• Turn the blades by hand so they are perpendicular to the driving direction of the mower. Measure the distance from the floor to the outer-most tip of both blades. If they are not the same, loosen the left-right adjustment lock, adjust the height, and recheck. Repeat until both ends are the same distance from the floor.

I check the mowing deck every time I sharpen the blades, just because I’m a little hard on my mower. I’ve been known to stumble getting on or off it and step on one side of the deck or the other.

Summary

That’s it! The mower is all ready for another season! We’ve changed the fuel filter, cleaned the air filter, changed the oil, cleaned and gapped the spark plug, sharpened the blades, checked the tire pressure, and leveled the mowing deck. A little TLC like this, and your mower should last you much longer than anyone expects it will. That will save you a lot of money in the long run, as well as give you some bragging rights when your neighbor is on their third one before you’ve worn yours out. In other posts, I will get my trimmer and blower ready for mowing season.