lawnmower care through all seasons tips




Lawnmower

Lawnmower Tips, For all Seasons

Lawnmower Tips to Keep a Lawnmower in Good Shape, Through All Seasons.
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Storing a four cycle engine Lawnmower for the winter

A lawnmower requires care and maintenance just like any other gas engine. To store a lawnmower for the winter it is important to remove the fuel in the gas tank and carburetor. If the fuel tank is near empty, run the lawnmower until it quits, otherwise drain out the fuel and use it in your vehicle. Fuel left for several months will deteriorate and possibly not support combustion.
The fuel sitting in the carburetor can turn into “goop” which can plug up small fuel jets inside the carburetor, and prevent fuel from reaching the combustion chamber.
Old fuel coats the spark plug with an oily substance that can “short” out the spark, preventing the engine from starting.
Stale gasoline smells like varnish or paint and is dark yellow. Drain the fuel from the fuel tank and then run the engine until it quits.

Some lawnmowers have a shut off valve in the fuel line, if the lawnmower has no shut off valve on the fuel line, drain the tank and run the engine until it uses all the fuel within the carburetor before storing.
A meat basting kitchen tool works well for sucking up small amounts of fuel from the fuel tank. The baster can be found in most dollar stores, metal ones are best, keep in your tool box and only use it for this purpose.
The best and sure way to deal with the fuel, is to drain and empty the fuel from the lawnmower and fuel container into your vehicle, and buy new fuel in the spring.

If you are storing fuel, place it into an airtight container, keep the container vent closed, and keep in a cool dry place away from sparks and flames.

Fall Maintenance

Do lawnmower maintenance in the fall, in the spring you may have too many other things to do, and the maintenance may not take place.
Best to change the oil in the fall, unchanged oil left in the engine over winter has acids, gums, soot, water and oxidized oil which can cause corrosion to the engine.

Clean or replace the spark plug, if the spark plug shows abnormal wear, replace with a new, exact replacement.

 Spark Plugs

The correct size spark plug is necessary. If the spark plug is too long, the end will hit the top of the piston resulting in damage. If the spark plug is too short, it could result in miss-fires.
If you have bought a secondhand lawnmower, keep in mind that the spark plug in place, might be the wrong sparkplug, for the engine, somebody could have changed it wrongly.
Check the specs for the correct spark plug. Spark plugs are not too expensive, and need to be changed once a year. They can be maintained; by removing, the spark plug and scraping off the carbon. Use a fine screwdriver to get down deep on the sides of the electrode and finish up with a wire brush overall. Check the spark gap and reset if necessary. A common gap is .030. Never try to remove a spark plug from a aluminum head, when it is hot as this could cause the threads to strip.

Clean the air cleaner, they become clogged through the season with dirt and grim.

 Cleaning Air Filter

Clean the air filter at least once a year as it does get plugged up with grass and dust.
Dirt in the filter, restricts the airway, which acts as if the choke is on, drawing in more fuel and less air; this makes a bad fuel mixture.
A smooth running engine needs a clean air filter. The air cleaner is located near the front of the engine, attached to the carburetor, behind some sort of easy remove cover (usually located on the left front side of the engine. (looking from the back side).
Remove the cover and filter, brush out the larger particles with a paintbrush. Then with a vacuum cleaner, vacuum out the filter. You can clean the air filter several times before it needs replacing, and if you are careful, it may last the life of the engine.
Clean a Polyurethane air filter every 25 hours of use. Wash in warm water and detergent, squeeze dry in a clean cloth. Apply a few drops of oil and squeeze out by hand.
Reassemble the filter and cover to the engine..

Drain the fuel from the tank and run the engine until it quits.

Sharpen and balance the cutting blade, a sharp blade makes a clean cut, a dull blade breaks the grass, causing split ends.

 Sharpening Cutting Blade

The cutting blade needs sharpening every season. A dull blade rips the grass, instead of cutting, ragged, torn grass are susceptible to disease.
Before working on the blade, remove the spark plug wire and make sure the controls are in the off position.
Some lawnmowers have a built-in wind-up spring, start action; make sure the spring is discharged before working on the lawnmower.
To discharge the windup spring, remove the sparkplug wire and attempt to start.
Turn the lawn mower on its side, just enough to get at the bolts holding the blade in place. Do not turn the lawnmower right over as this allows oil in the crankcase to slip past the piston into the combustion chamber. Keep the spark plug side of the engine up.
Take a good look at the way the blade is held in place, before removing. There may be two or three pieces involved and you need to know how to reassemble. (Mark each piece with a marker pen).
Remove the bolt, or bolts and the cutting blade.
Scrape out all the dirt and grass accumulated under the metal deck. A big screwdriver or sharp stick works well for doing this.
Take the cutting blade and sharpen it with a file or electric grinder. Sharpen to 25 degrees, not razor sharp, but leave a 1/64 tip. A razor sharp edge will curl and dull very quickly. Follow the original pattern, you only need to sharpen the tips, approximately one-two inches. Sharpen both the same amount, to keep the blade in balance.
Take the blade and place the center on a small finishing nail driven into the end of a workbench. Place one drop of oil on the nail in the center of the blade. If the blade is off balance and will not stay horizontal, file or grind a little more off the heavy side. Normally a quick touch up does not change the balance.

Check Cutting Blade For Cracks

With a screwdriver, hang the blade from its mounting hole and strike it gently with a hammer. A good blade will ring like a bell. A cracked blade will give a thud.


Reassemble the blade to the lawnmower and tighten securely. Re-check tightness again after first use.
If you are in doubt which way the blade goes, keep in mind that the sharpened tip will be the lowest point and will be positioned so as the arm rotates the grass will be thrown upward.
Re-connect the sparkplug wire.
Top up the fuel and your ready to go!


Clean grass from cooling fins and the lower deck, a clean engine is a healthy engine..

The best time to clean the under side of a lawnmower is when the gas tank is low or empty. Do not turn the lawnmower up-side-down, as the oil in the crankcase can work its way past the piston into the combustion chamber. Just lift the lawnmower onto its side, with the gas tank lid on the upper side. Use a sharpened stick to chisel and scrape away the packed grass and grim. Finish up by washing with a garden hose.
Keep in mind a well maintained mower will last ten years or more.


 Spring Time

Forgot to drain the fuel?

In the spring time, if you find you have forgotten to drain the fuel from the tank, try removing the spark plug, clean the sparkplug thoroughly, pour about a teaspoon full of clean new fuel directly into the combustion chamber, re-install the sparkplug.
Take all safety precautions when handling gasoline.
Choke on full, hook up the sparkplug wire and give the starting rope a quick pull. If the engine “starts”, this may be enough to purge the old fuel from the system, unclogging the carburetor. As the motor starts, slowly move the choke into the full open position, and let run for a few minutes.

If the engine runs, topping up the tank with fresh fuel may help to wash out the stall fuel in the carburetor and get the lawnmower running for the new season.
If this does not work, you may need to add a chemical such as Gum out to the fuel to clean out the carburetor.

Alternative to removing fuel

Instead of draining the fuel from the engine for winter storage, add a little fuel stabilizer before storing. Add stabilizer and run the engine for a little while to allow the stabilizer to enter the carburetor.

Remove the spark plug and squirt a few drops of oil into the sparkplug hole. Replace spark plug and spark plug wire.
In the Spring when its time to re-fuel, buy unmarked gas, it's cheaper, as there is no road tax included in the price.


 Battery

A battery will lose its charge when it is not used, a dead battery can freeze and bust open. Trickle charge the battery every couple of months during the winter. In the springtime, charge the lawnmower battery fully.
Check the mower for any loose nuts, bolts, and fasteners. Check for fuel and oil leaks.


 Getting the Most Power Out Of a Lawnmower Engine

Get top power out of your lawnmower engine by changing the oil on a regular basis, cleaner oil, less friction.
Keep the cutting blade sharp, a dull blade robs your engine of power.
Keep the air cleaner clean; lack of air and the engine will not perform at its peak.
Correct adjustment of low and high speed carburetor adjustments; proper fuel air-mixture creates the most power within the combustion chamber.
Carburetor Adjustment

Clean or new sparkplug, helps give a complete combustion for added power.
Keep the engine clean, an over heated engine loses power.
Use clean new fuel, stale fuel does not produce full power.


Checking Level of Oil

Check the oil level before operating the lawnmower. Place the lawnmower on a level surface to get a true reading.
Oil dipsticks usually have a low mark and a full mark. Top up to the full mark, oil dissipates heat.
When checking the level screw out the dipstick wipe it off with a clean rag and then just dip it into the oil fill hole, remove and check the level, unless the instruction manual says to screw it in to check the oil. The engine needs a proper level of oil to help cool the engine; a too low level can lead to overheating. A too high level can reduce power. If the engine doesn't have a dip stick, then clean around the fill plug, remove and top up the oil to the fill level.

Condition of Oil

Check the oil on the dipstick for color and condition. Oil in good condition is clear light brown in color. Oil in bad condition is black in color and has a dirty look.
Small lawnmower engines do not have an oil filter, so grit builds up quickly, and loses its lubrication and cooling effectiveness.


Changing Oil

In the fall, after the last cut, while still warm, change the oil, to prevent the grit and acids from eating away at the engine during the winter.
There is a drain plug somewhere on the lower part of the engine. Remove it and drain the oil into a pan and take it to a recycle depot.
If the engine does not have a drain plug, tip the lawnmower on its side and drain the oil out the dipstick-filler hole, do this while the engine is still hot. Hot oil picks up dirt and suspends it better.

Wear eye protection while changing oil, so you do not get splashed in the eyes, and keep hands away from the oil, as it is very hot. Replace the plug and refill with new oil, using 10-30 or whatever type and grade of oil the manufacturer recommends. Most engines will not take a full liter of oil, so stop and check the level several times while filling.
Overfilling is not good for the engine. The rotating crankshaft will hit into the overfilled oil level, and throw up a lot of oil. The engine will run rough and more oil will reach the combustion chamber than normal, resulting in poor combustion and a lot of blue smoke.
Burnt oil in the combustion chamber leads to a fouled spark plug and build-up of carbon on the combustion chamber, and piston head. Heated carbon causes "dieseling" (engine continues to run after it is shut off).
If a build-up of carbon takes place, remove the head and scrape away the carbon away from the combustion chamber and the top of the piston.
A new head gasket is necessary when replacing the head. Tighten the head bolts need to in a criss-cross fashion (first one bolt on one side, then on the other side) they need to be torqued to the correct tightness, with a torque wrench.


 Removing a Seized/Rusted Blade Bolt

To remove a seized bolt, tap the end of the bolt straight on, with a hammer several times; this will help release the bolt threads. Add a couple drops of penetrating oil to the bolt shaft, wait a few minutes and remove bolt. Take note of how the bolt , blade and other parts go together, so you will know the proper order in putting it back together.


 Starting Lawnmower

Place the lawnmower on level ground or sidewalk, not on lawn where blade can contact high grass. Check the level of oil and add some if necessary. Turn the fuel shutoff valve to fully on, if the lawnmower has a shutoff valve. Shift the starting lever to full start position; this will also turn the built in choke to fully on. Give the rope a couple of pulls, until the engine attempts to start. Then move the start lever so the choke is off or you may end up flooding the engine with fuel. Give the rope a couple more pulls until the engine starts, then move the choke about half on until the engine warms up a bit, then you can move the lever so the choke is completely off. If the engine has a choke separate from the start control, then operate the throttle and chock to get the same result. If your lawnmower has a priming bulb, give it three pumps before attempting to start.


 Lawnmower Starts, but Runs Rough

If your lawnmower starts but runs rough, check to see that the manual choke is fully open, providing your lawnmower has a manual choke, some lawnmowers do not have a manual choke. The other common fault is a plugged up air cleaner. This conditions acts like a closed choke. Either one of these two conditions will cause an engine to run rough because of the wrong mix of fuel and air to the combustion chamber.
To clean the air filter, open the cover to the air cleaner assembly, which is located next to the carburetor. The cover either is a snap on type, or has one screw holding it on. Remove this and remove the foam filter. Brush off the grime and vacuum out the dirt, if an engine runs for long period with a dirty air cleaned, the spark plug will become carbonized up and the engine will run rough. Clean or change the spark plug.




 No Spark - Won't Start

Always try a new spark plug first before any test.
The most common problem when there is no spark, is the off control switch mechanism. When you slide the off switch devise to the off position, a mechanical arm situated near the carburetor swings over and shorts out a wire that goes to the spark coil. If the sliding arm goes out of adjustment, it will short out the wire at the wrong time. Check to make sure the sliding arm is free, and adjusted right. Check the wire, that goes to the coil for defects.
A bent key in the keyway will change the timing of the engine and may prevent an engine from starting, this can happen by hitting a rock or some solid object on the lawn while cutting. If this happens, a new key needs to be installed.


 Bag Care

If you are using a bag to catch grass on your lawnmower, the bag has to be able to "breathe" to work properly. To get the proper suction and action to lift the grass from the blade the moving air must move freely through the bag. The bag fabric will impact with debris over time, take a hose and wash the bag as necessary.


Engine Care

Combustion engines need air to cool. Regularly remove debris from the cooling system vents. Overheating can destroy an engine


 Lawnmower Runs A Short Time, Then Quits

The fuel tank cap has a vent hole to allow air to enter the tank and replace the fuel that is leaving. If the vent hole is plugged, a vacuum takes place in the fuel tank as the engine runs that prevent fuel from leaving the fuel tank. Clean the dirt off the top of the tank cap and use a straight pin of fine wire to clean the vent hole, be careful not to enlarge the hole.


 Pull Rope - Won't Return

The pull rope returns by a wound up spring. The reasons for not returning are broken spring, rusted spring or dirt and grim in the spring coil mechanism. You can try adding a few drops of oil into the spring and working the rope back and forth. If this does not work, then the spring needs to be removed and cleaned, oiled or replaced. This is not a job for someone who has not done the job before. The spring can fly out and cause injury! Unbolt the complete mechanism, held in place with three bolts. Take the complete unit to a lawnmower repair shop and have them do the repair.


Pull Rope - Won't Turn Engine Over

If you had the lawnmower totally upside-down for a while, oil from the crankcase, may have leaked pass the piston and filled the combustion chamber. The piston has no place to go; the engine appears seized-up. Remove the spark plug and place lawnmower on its side and pull on the starting rope until all the oil is pumped out the sparkplug hole. Add a little fresh fuel into the sparkplug hole and place a fresh sparkplug into place. With choke off and throttle set to full throttle, start the engine. There will be a lot of blue smoke until the oil is burned out.


 Engine Vibrating

Engine vibration is a condition in which the engine shakes back and forth. Loose engine mounting bolts can cause engine vibration.
A very serious condition is a cutting blade bolt coming loose. If this happens, shut the engine down right away, as the blade could come right off and cause serious injury. Other causes for vibration, is out of balance cutting blades. A unbalanced and bent blade can also cause excess vibration.


 Shutting Engine Down

Allow engine to come to an idle before killing the ignition, unburnt fuel, can pass into the exhaust system, igniting and cause a back-fire.
Do not stop an engine by removing the spark wire, as this can cause a high voltage spike in the secondary windings, which may get into the primary windings where it can damage the coil or solid state components.


 Two Stroke Mixture

Some engines use a 32 to 1 mix, others a 50 to 1 mix (50 parts fuel, 1 part oil). Check the owner’s manual or the fuel tank decal for the correct mix. Always shake the fuel can after dumping the oil into the fuel.
Two-cycle (oil is added to the gas) engines need the carbon removed from the exhaust port every couple of years. To clean the carbon, remove the spark plug lead and muffler. Rotate the crankshaft until the piston covers the exhaust port. With a sharp stick, scrape away the carbon. Rotate the engine over several times to blow away any loose carbon. Replace the muffler and spark plug lead.


Right or Left

Mowers left and right side is determined by standing behind, and facing the mower.


 Uneven Cutting

If the cutting height is incorrect, the cut will be uneven. To adjust the cutting height, place the lawn mower on a flat surface and check the heights, front, back and sides. All wheels should be the same height.


Fairy Ring

If you are cutting the lawn on a different property than your own, and they have a lawn infected with fairy ring, dandelion, or anything else that you don't want on your own lawn, then remember to wash your lawnmower and wheels with a hose before returning home. It is easy to transport unwanted spores and seeds with your lawnmower to your own lawn.


 Lawnmower And Blue Smoke

Blue smoke is an indication that the engine is burning oil. Check to make sure you have not overfilled the oil in the crankcase. If the oil is not changed often, the rings will become carbonized, and will not do their job. Try a chemical approved for this condition. If the engine is very old, the rings may be well worn and oil is entering the combustion chamber. Try heavier weight oil, this may help. Always keep the air cleaner free of dirt, grass and grime; a plugged up air cleaner is like running the engine with the choke always on.

Black smoke is an indication of too rich a fuel air mixture.


 Engine Surging

Lawnmowers have a device to maintain constant engine speed over different cutting conditions. The way this is accomplished, is by an air driven control system. The cooling fan for the engine also drives a vane type lever by air pressure, which is linked to the carburetor, to maintain a constant speed. If the vane gets clogged up with grass, etc. it will not be able to do its job properly. The vane has to be able to move freely, and if it can't, surging will happen. Cleaning up the mechanism should correct the problem. Also don't overlook a plugged air cleaner.


 How A Choke Works

When you put the controls in the full choke position, a small metal cover closes in the air intake channel, on the outside end of the carburetor between the air cleaner and carburetor. This is part of the carburetor. The purpose is to reduce air and increase fuel, for a richer fuel-air mixture. Choke is needed on cold engines, but not required on a warmed up engine. Leaving it in full choke position after the engine is warmed up, will cause the engine to run rough, and carbon up the spark plug. You can start with a fully closed choke and gradually reduce it as the engine warms up. A choke does not usually require any maintenance other than setting the adjustment cable, so it closes completely and opens fully.


Buying A Mower

Watch for sales. Buy off season or watch for sales in late August.


 Lawnmower Safety Tips

Do Not cut the lawn bare footed or in sandals, always wear shoes or boots, this gives you stability and adds some protection to your feet. Lawnmowers can throw out objects that might be lying in the grass. Stop cutting when someone passes by and keep small children away from the lawnmower. It is a good idea to wear safety glasses. Give the lawn a quick look over before cutting, and remove any object that could be hurled by the rotating blade.


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Lawnmower Tips to Keep a Lawnmower In Good Condition, Through all Seasons.