How do I know if my lawn mower needs a new spark plug?

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. Any damage to the spark plug requires its replacement.

How do I know if my lawn mower spark plugs are bad?

The more worn or dirty spark plugs are, the greater the tug on the rewind and more effort is required to produce an adequate spark. If you haven't turned on your engine recently, your mower won't start and/or you have to tug repeatedly on the rewind to start the engine, a damaged spark plug may be the culprit.

When should I change the spark plug on my lawn mower?

For standard lawn mower and small engine maintenance, you should check and/or replace spark plugs: once a season. every 25 hours of use. if your lawn mower our outdoor power equipment won't start.

How do I know if my spark plug need changing?

Will a mower start with a bad spark plug?

A dirty or fouled spark plug can cause your lawn mower to not start. It can also work itself loose, causing issues. If the spark plug appears to be seated correctly but the engine doesn't start, a new one may be in order. For a few dollars, this easy fix can get your small engine working again.

How To Check, Clean

What happens when a spark plug goes bad on a mower?

A bad spark plug often causes an engine cylinder to misfire or sound like it's struggling. The engine might even stall out completely while you are mowing. You may also notice that it becomes increasingly more difficult to restart the mower each time that it dies.

What does it sound like when you need new spark plugs?

Keep your ears open for any rattling, pinging or knocking sounds—these are another bad spark plug symptom. If your vehicle's engine is making any unusual sounds or vibrations while idling, your vehicle's spark plugs may not be functioning properly to keep the engine running smooth.

How can I check myself for spark?

How long does a lawn mower spark plug usually last?

The standard life of a lawn mower spark plug is 25 hours.

It doesn't matter how well you take care of your lawn mower, spark plugs wear out after about a season's use.

How long do spark plugs last in a mower?

Spark plugs of lawn mower must be changed when it has an adverse effect on the performance. Most manufacturers design spark plugs for a maximum of two years. To ensure optimum engine performance, changing the spark plugs once every year or after 30 hours of use is a good practice.

Why is my lawn mower turning over but not starting?

Dirty Air Filter

An air filter that's not letting enough air into the motor can inhibit combustion. Locate the air filter on your mower and remove the plastic cover. If the filter is covered in dirt, grass, or some other contaminant, this may be the reason for your lawn mower turning over but not starting.

Why does my lawn mower only run for a few seconds then dies?

If your lawn mower starts, runs briefly, then dies these are the four most common reasons that's happening: Dirty carburetor / clogged carburetor bowl. Old gasoline that has gone bad. Dirty or defective spark plugs.

What does a weak spark look like?

A good spark will be blue-white and will be plainly visible in daylight. If a good spark is present, the problem is probably not in the ignition system. Check the fuel system and/or stark timing. Weak sparks are orange or red and may be hard to see in daylight.

What does failing spark plugs sound like?

Sometimes, especially while accelerating, you will hear your engine making a distinct knocking sound. That sound is caused by your spark plugs not detonating properly and igniting all the fuel. The fuel and vapor that did not ignite eventually will catch fire and detonate.

What would cause a lawn mower to run for a few minutes then stops?

If you've got a lawn mower that runs for 30 minutes then dies, the most common culprits are: a faulty spark plug or ignition coil, blocked fuel delivery, and air supply problems. A variety of parts are involved here, but the first things you'll want to check out are the spark plug, carburetor, and fuel cap.

Why does my lawnmower run for 10 minutes then dies?

As the fuel level drops, a vacuum begins to form in the fuel tank because air can get in to fill the space the consumed fuel occupied. After about 10 or 15 minutes, the vacuum will become strong enough that fuel will stop flowing to the carburetor and the lawnmower will die.

What is the first thing to check if a lawn mower won't start?

Can a dirty air filter cause a lawn mower not to start?

Before the incoming air enters the carburetor, it passes through an air filter to remove dust and dirt. When the filter is doing its job, it may get clogged up with debris removed from the air and not allow a sufficient amount of air into the carburetor and prevent the engine from starting.

Why does my lawn mower keep dying?

The spark plugs are worn or damaged

If you find that your lawnmower keeps dying, or keeps stalling while cutting grass, then inspect the spark plugs. Look for signs of damage or wear. Something as simple as a cracked porcelain insulator can mean an electrode has been damaged or burned away.

Can you clean and reuse spark plugs?

You can clean a fouled spark plug and reuse it, but it might not function as well after that. If your spark plug is too worn or dirty to clean easily, you'll need to replace it.