Identifying Strange Lawn Mower Noises

Any lawn mower can make strange noises from time to time. This article identifies several of the most common noises and suggests how to best fix them.

Fortunately, identifying these noises can help you diagnose any potential problems and keep your lawn mower running smoothly.

One common issue with lawn mowers is engine popping sounds. This noise can be alarming, but it’s usually an indication that your lawn mower is backfiring.

When you hear this sound, it’s important to identify the root of the problem immediately.

Another common noise is rattling or banging. This often indicates that parts have worked themselves loose over time or were not tightened properly in the first place.

If the sound is accompanied by excessive mower vibrations, the engine can even bounce around on the engine mount. Checking and tightening all attachments, the blade, flywheel, and any chassis parts can fix this issue.

Common Noises

When you are mowing your lawn, you might hear some strange noises coming from your lawn mower.

These noises can be alarming, but they don’t always indicate a serious problem.

In this section, we will discuss some common noises that you might hear from your lawn mower and what they might mean.

Rod Knock

Have a listen to what rod knock sounds like:

Rod knock sounds like metal parts hitting each other forcefully inside the engine. In 25+ years of repairing mowers I find that this sound is never good news.

You can confirm rod knock by looking for metal shavings in the oil. As the parts continue hitting each other the damage leads to metal breaking off the parts (best case scenario), or to catastrophic engine failure.

Don’t ignore a mower engine that sounds like it’s being hit with a hammer, it needs immediate attention by a small engine mechanic.

Squeaking

If you hear a high-pitched squeaking noise coming from your lawn mower, it could be due to a loose belt or a worn-out pulley.

You can check the belt tension and pulleys by turning off the engine and removing the spark plug wire. Then, use a wrench to check the tightness of the belt and pulleys.

If you find any loose parts, tighten them up or replace them as necessary.

Grinding

A grinding noise coming from your lawn mower could be due to a damaged blade or a worn-out bearing.

You can check the blade by turning off the engine and removing the spark plug wire. Then, use a socket wrench to remove the blade and inspect it for any damage.

If the blade is damaged, replace it with a new one. If the bearing is worn out, you will need to replace it as well.

Rattling

A rattling noise coming from your lawn mower could be due to a loose or damaged part.

You can check for loose parts by turning off the engine and removing the spark plug wire.

Then, use a wrench to check the tightness of all the bolts and nuts on your lawn mower.

If you find any loose parts, tighten them up or replace them as necessary.

Causes of Noises

When you hear strange noises coming from your lawn mower, it’s important to identify the cause of the problem quickly.

Here are some common causes of noises in lawn mowers:

Loose Parts

A common cause of noise in lawn mowers is loose parts. If you hear rattling or clunking sounds, it could be due to loose bolts, nuts, or screws.

These parts can become loose over time due to vibration and normal wear and tear.

Check the engine, blade, and other parts to ensure they are securely fastened.

Worn Out Parts

Another common cause of noise in lawn mowers is worn-out parts. If you hear a grinding or squealing sound, it could be due to worn-out bearings, belts, or pulleys.

These parts can wear out over time and need to be replaced to ensure your lawn mower operates smoothly.

Dirty or Clogged Parts

Dirty or clogged parts can also cause noise in lawn mowers.

If you hear a choking or sputtering sound, it could be due to a dirty air filter or a partially clogged carburetor.

These parts can become clogged with dirt, dust, or debris, which can affect the performance of your lawn mower.

Clean the carb or replace the air filter to keep your lawn mower running smoothly.