Black, dry soot on the electrodes and insulator tip indicates a carbon-fouled plug. This can be caused by a dirty air filter, excessive driving at low speeds, too rich of a fuel/air mixture or idling your vehicle for too long.
Consequently, why is my spark plug black on my lawn mower?
A black, feathery carbon deposit on your spark plugs can be an indication of a weak spark or an overly rich fuel mixture. Causes may include a stuck choke, misadjusted or heavy carburetor float, a leaky injector or carburetor needle valve, low coil output or high resistance in your spark plug wires.
One may also ask, why does my lawn mower spark plug keep fouling? Carbon Buildup
A fuel and air mixture that is too rich is another cause of incomplete combustion. If the carburetor sprays too much fuel into the combustion chamber, the fuel burns cooler. The smoke that results fouls the plug as well as the air filter and the spark arrestor that covers the engine's exhaust port.
Keeping this in view, what does a bad spark plug look like lawn mower?
Its center electrode should have a flat top. If its top is rounded, then the spark plug must be replaced. Look for cracks or chips in the spark plug's porcelain sheath as well as pitting on its firing electrode.
WD-40 removes carbon residue and keeps moisture away from spark plugs and spark plug wires. WD stands for Water Displacement, so if your spark plugs are wet or you need to drive moisture away from ignition distributors, for example, WD-40 is a product you should have handy!
Rewind the rope around the flywheel and turn the lawn mower's ignition switch on. Pull the rope to spin the flywheel and watch for a spark on the original spark plug. If a spark is present, the spark plug is working properly. An absence of spark will require replacement of the spark plug.
For the optimal functioning of your lawn mower, the spark plug has to be in good condition – which means it must not be wet. If you notice that it is wet, you can take various steps to correct the problem, or you can choose to replace the plug itself so that it does not lead to lasting system damage.
Technically, yes, you can clean spark plugs, however, in most cases it's not worth it. We do not recommend it for a number of reasons. Ultimately, you won't get the same performance from a cleaned plug as from a new plug. Electricity discharges best from sharp edges.
What Causes Carbon Fouling on a Spark Plug? Carbon fouling on a spark plug is caused by a problem with the fuel that you use. ... That can cause combustion problems, resulting in excess carbon that sticks very quickly to the hot parts of the spark plugs.
Typically, the consensus among the mechanical engineer community is that a spark plug for a lawn mower will last up to 25 hours of use. Some users simply prefer to replace it every mowing season as a part of their yearly lawn mower maintenance.Share to:FacebookTwitterPinterestEmail