Lawn Mower Maintenance
Properly cared for some lawn mowers have been known to last through the full lifetime of their owners. Learn lawnmower maintanence.
Lawn mowers take much of the work out of a thankless job. Properly cared for, some lawn mowers have been known to last through the full lifetime of their owners. These tips will help you properly take care of this hard working machine.
Begin each mowing season by changing out your spark plug. Check the papers that came with your lawn mower and find the engine maker's specifications to see what the gap should be set at. At the plug's threaded end you will find two metal electrodes. You will be setting the gap between these two electrodes. The best way to do this is by using a spark plug gauge's bending bracket on the L shaped side electrode to adjust the gap. Remove the old spark plug from your lawn mower and connect the wire to the new one. Lay the new plug's threaded surface on the engine and crank the engine. If you can see steady sparking between the two electrodes you should install the spark plug. In a case where you observe erratic sparking or no spark at all you will need to remove the sheet metal cover over the fly wheel to inspect the magneto coil. If the magneto coil is not damaged, check the entire length of the plug wires to see if you can find any damage there. When you find damage to either the magneto coil or plug wires they will need to be replace for your lawn mower to run.
On many mowers the magneto coil and the plug wires are a single component, so if there is any damage the entire component will need to be changed. If you can't find any damage to the plug wires or magneto coil you might need to have a lawn mower repair shop check the electronic ignition for problems. With older lawn mowers that do not have electronic ignitions, you will need to check the ignition points and adjust the gap instead. In this case, the points will be under the flywheel so you will need special tools to remove it. You can save yourself the bother of having to buy special tools by purchasing an electronic ignition conversion kit from you local lawn mower outlet and installing it on your lawn mower. This is a much less expensive alternative. When you have the kit installed you will never have to service your points again.
If you have a pull rope type starter you should check the rope for fraying, and if you find any, the rope should be replaced. Also check the spark plug wire terminals to make sure they fit tightly on the plug. Next you will need to check the air filter. To do this, remove the air filter cover and see if the filter is dirty. There are two common types of air filters. One is a plastic foam filter and the other is a pleated paper filter. If your air filter is dirty, the paper filter will have to be replaced. With the foam filter you can remove it and clean it by immersing it in kerosene. Continue squeezing the kerosene through the filter until it is clean and then allow it to air dry. When the air filter is dry you will need to soak it in clean engine oil until it is saturated and then gently squeeze out as much of the oil as you can. Reinstall it in your lawn mower.
Using a penetrating oil such as WD-40, spray the axles and the carburetor linkage. In a case where your mower has a belt drive or chain drive, check for slack by pressing on the belt or chain with your finger. If either shows signs of looseness it will need to be adjusted. You can tell if adjustments are needed with a belt drive if there is more than 3\4 inch deflection between the pulleys or with a chain drive is the deflection is more than 1\2 inch between the sprockets. To make this adjustment you should loosen the lawn mower engine to mower bolts and move the engine forward or back, whichever is necessary to properly tighten the belt or chain. If your lawn mower has a belt that is automatically tensioned by a spring loaded pulley you will not be able to adjust it. Replace the engine to mower bolts and tighten them.
Check your blade to see if it is dull or nicked. You can file away minor nicks but it should be sharpened by a professional. If the nicks are bad the entire blade should be replaced. Trying to sharpen the blade yourself could cause an unbalanced blade which will put an uneven load on the engine causing damage. Check the gas tank for gum which will form when gasoline is left in the gas tank through the winter months. If you find gum pour a pint of carburetor solvent into the tank before filling it with gas.
To prime the engine you should remove the air filter and put about 3 tablespoons of gasoline into the bottom of the filter housing and you are ready to start your mowing season. Around the middle of the mowing season you should again check your air filter and clean or replace it. Clean the body of your mower and change the engine oil while the motor is still hot. This is also a good time to check for any new nicks in the blade. When you are preparing to store your lawn mower for the winter either run the machine out of gas or empty the gas tank. Change the oil again and put about 5 tablespoons of oil in the spark plug hole. Start your mower and allow the oil to circulate for a few seconds before replacing the spark plug. Spray the outside of your mower down with WD-40 or another penetrating oil and cover it to protect it from dust and debris.