Easy Fixes for Mowers

A trim, even lawn is the pride of every garden, but what happens when your mower just won't cut it? Most problems can be fixed at home with tools already in your toolbox.

Sharpen and rebalance the blades

Your mower's blades will need sharpening once or twice a season to keep their edge. While You can do this job without removing the blades from the mower, taking them out gives better results and also allows you to balance the blades. Unbalanced blades produce vibration when they spin, putting stress on the engine.

Time needed to sharpen and rebalance mower blades: 30 minutes.

You will need: wire brush, household degreaser, wrench, broom handle or length of wood, and metal mill file.

1. Always work on a cold mower. For electric models, ensure the unit is unplugged; for gas mowers, disconnect the spark plug lead, tighten the gas cap, then flip the mower deck onto its side. Soak up any spilled fuel with a rag.
2. Wedge a length of wood between the mower's deck and blade to prevent the blade from turning. Using the wrench, remove the bolt(s) securing the blade, turning counterclockwise. Make a mark on the lower face of the blade so that you know which way to replace it after sharpening.
3. Remove the blade. Using the wire brush and household cleaner, strip its surfaces of any grease and debris .
4. Holding the blades firmly, preferably clamped in a vise, sharpen the cutting edges with the mill file, following the existing shape of the blades. Sharpen only on the push stroke — you should be able to feel the file biting into the soft steel blade and it should take no more than 50 strokes or so to achieve a good edge. This doesn't need to be razor sharp, just smooth and uniform.
5. Balance the blade. Hang it through its central hole on a nail driven into a wall. If one side drops lower than the other, file a little more from its cutting edge until the two sides are balanced.
6. Refit the blade, ensuring it is in the correct way. Tighten the nut as hard as you can.

While major repairs should be left to the professionals, there are a number of mower tune-ups you can do yourself.

Air filter

A mower that fires up and quickly dies may have a dirty air filter. Cleaning the filter is simple.

Spark plug

A mower that won't start may have a dirty or cracked spark plug. Changing the plug is only a 15-minute job.

Height adjustment

An uneven cut may mean you need to level your mower using the levers at each wheel.

Fuel system

Coughs and sputters can mean a problem in the fuel system. Track down and fix the problem.

Carburetor

The hoses connecting the fuel supply to the carburetor can degrade and need to be replaced.

Cutting blade

If your mower rattles or cuts unevenly, it may have a loose or blunt blade, which you can tighten and sharpen.

Before working on your gas mower, switch off the engine, disconnect the spark plug and let the unit cool down. Wear protective gloves and use a stick, rather than your hands, to remove any obstructions near the blades.