Top 8 Causes of an Overheated Husqvarna Lawnmower Engine

Stop the mower immediately if you detect even a hint of engine heat, figure out what’s causing it, and fix it before the engine overheats and breaks.

Overheating can occur in the engine of a Husqvarna lawnmower if the oil level is too low, the wrong type of oil is used, the air filter is clogged, the cooling fins are clogged, or the engine guard is missing.

Overheating can also be caused by a clogged mower deck, dull mower blades, or a ground speed that is too high for long, thick, or wet grass.

Use caution and observe all safety instructions provided in your Husqvarna manual. Before making any repairs, you should turn off the mower, take out the key, let the engine cool completely, and then remove the spark plug boots.

Before diagnosing, repairing, or operating, make sure you’ve read and understood all of the safety instructions included in the equipment’s operator’s manual.

In the event that you lack the necessary knowledge, experience, or physical ability to safely complete the repair, it is recommended that you seek the assistance of a professional.

Husqvarna Lawn Mowers Overheat—Why?

Mistakenly Putting Diesel Fuel in a Gas-Powered Husqvarna Lawnmower

With a gas-powered Husqvarna mower, the engine oil has two purposes: it lubricates the engine so that the moving parts can do their job smoothly, and it helps keep the engine cool.

Oil for a lawnmower’s air-cooled little engine is different than oil for a lawn tractor’s liquid-cooled big engine.

Husqvarna’s line of gas-powered lawnmowers, from walk-behinds to zero-turns, are powered by tiny engines that run on air-cooled engine oil with a high percentage of zinc, such as Briggs & Stratton, Kohler, and Kawasaki.

As a chemical, zinc acts as a refrigerant. As water in liquid form is utilized to cool the engine, regular motor oil, such that used in a car, does not contain much zinc.

See the table below for details on the optimum oil to use at various temperatures. For specific oil recommendations, please use this table in conjunction with your user manual.

Use SAE30 or 10W-30 engine oil in your Husqvarna mower’s engine, as recommended by the manufacturer.

However, you may need to switch to a different oil viscosity (such as 20W-50 in hotter climates or 5W-30 in colder ones) depending on the conditions.

The ANSWER is to change the oil in the engine from the incorrect type to one designed for use in air-cooled engines.

Top 8 Causes of an Overheated Husqvarna Lawnmower Engine

Husqvarna Mower With Low Engine Oil Level

To ensure smooth motion of the engine’s internal components, regular lubrication is essential. Low oil levels cause the engine to overheat due to increased friction.

If you keep an engine running with a low oil level, the oil will thicken. This is a certain way to wreck an engine.

Before you start the mower, you should make sure the oil is at the right level. If you find that your oil level is low, you should top it off.

You should check for the following if your Husqvarna mower frequently needs oil:

  • Leaking Oil – Inspect the engine compartment for oil leaks. Once the source of the leak has been located, the leaking gaskets should be replaced.
    If your mower has a filter, check it out, too. Verify the integrity of the oil filter’s seal.
  • Oil flames out? It could be a clogged air filter. When an air filter becomes clogged, oil is wasted and the engine has to work harder. If the filter becomes too dirty to clean, you should replace it.
  • Overheating while operating can cause an engine to burn oil. A issue with the valves or rings may potentially cause this symptom. The engine in your mower has to be checked out, so take it in for service as soon as possible.

A solution is to check the oil level in the engine and top it off if necessary. If you suspect dirty oil as the source of your engine’s unpleasant odor, a comprehensive oil change is the best course of action. Perhaps the oil thickened as it was heated.

Repeatedly operating your Husqvarna with insufficient engine oil could have led to the persistent troubles you’ve been experiencing even after you’ve changed the oil.

If your lawn mower needs servicing, you should bring it to a Husqvarna dealer or a small engine repair shop. To fully assess the situation, the technician will need to do more tests.

The Cooling Fins Are Broken or Clogged

To maintain a cool operating temperature inside the cylinder head and engine block, air is forced outward by the cooling fins.

  • There is a fan mounted on the top of the engine. It draws in cool air from the outside and directs it downwards into the engine.
  • The air is drawn into the top of the engine, where it circulates, and then expelled downwards.

If the cooling fins grow dirty or are broken, they won’t be able to flow enough air around the engine to keep it cool. The engine may overheat as a result.

The answer is to take off the top of the engine and clean the radiator. Replacement of broken fins is required if any are discovered. Do away with grime from the engine cover and the area immediately surrounding it.

In the future, this should be a regular element of your upkeep.

Cleaning your Husqvarna’s engine might make the situation worse by forcing water and dirt into the moving parts. Avoid making a bad situation more worse by spraying water into the engine while cleaning your lawn mower.

Husqvarna Lawnmower Without Engine Guard

The engine shield is essential for preventing overheating by allowing cold air to circulate around the engine. If a guard isn’t there, the area’s cool air will escape.

The solution is to make sure the engine guard is in the right spot. Make sure the protection is properly secured by tightening or replacing the screws that hold it in place. Supplant a broken or absent protector.

Husqvarna Lawnmower With A Clogged Air Filter

The air filter serves to clean the air entering the engine, preventing dirt from accelerating engine wear.

Without regular maintenance, the filter can get so clogged with dirt and debris that it prevents air from reaching the engine.

The Husqvarna engine may get too hot to the touch if it needs to work harder to dissipate the heat.

ANSWER: Take out the filter and look at it. Put some light through the paper piece. If the amount of light is satisfactory and the filter appears to be in good shape, you can clean it by tapping it against anything solid and replacing it.

To the contrary, if the illumination is poor or nonexistent, the air filter is damaged, or it is particularly dirty and dark in color, a new filter should be installed.

Certain Husqvarna mower engines have what is called an inner air filter and pre-filter, which consists of a thin filter housed inside a larger, paper air filter designed to resemble a canister. Some elect to utilize a foam pre-cleaner that encases a conventional paper air filter.

These filters assist shield the motor by capturing debris before it may enter the intake system.

If you want your mower to last as long as possible, you should clean and replace the air filter at regular intervals throughout the year.

If you use your Husqvarna in dusty conditions or mow more frequently than the average homeowner, you may need to replace or clean it more frequently.

Don’t be stingy; instead, do what you can to extend the life of the filter. Even though I try to save money whenever possible, I cannot help but invest in upkeep necessities.

If debris gets into the engine, I’ll have to spend a lot more money fixing or replacing it than I would on an air filter.

Husqvarna Lawnmower with a Clogged Deck

Under the mower deck, grass trimmings, dirt, and other debris will accumulate. This necessitates routine scraping of the Husqvarna deck.

For a clean shave, some people use the space under the deck to generate a draft. The blades, baffles, and cutting deck of the mower are all engineered to work together to create a powerful vacuum that lifts the grass and cuts it cleanly and evenly.

Debris accumulation not only reduces cutting quality but also increases engine strain as blades attempt to cut through the obstructions.

Use a deck scraper to remove debris from the mower’s deck. It is also possible to use a putty knife or wire brush.

If you want to keep the mower deck clean, you should inspect it often.

Although there are coatings available to apply to the underside of the mower deck, which can aid in preventing buildup, this is not a common practice. It’s important to note that these items aren’t miracle workers and you’ll still see some accumulation despite using them.

Check out DuPont’s spray if you’re in need of a spray for your mower deck.

Cutting damp grass and not using the mower at full power both contribute to clumping and buildup under the deck.

Husqvarna Mower with Dull Blades

The issue of a clogged mower deck is exacerbated by dull mower blades.

The engine will have to work harder, and it may overheat as a result, if the blades have to be turned through trash under the deck while they are dull.

The ANSWER: Blades on lawn mowers need to be sharpened and inspected frequently. Mower blades need to be sharpened around every 25 hours or twice a season for the typical household.

To learn more about adjusting the blades on your Husqvarna mower, check out the dedicated guide, entitled Replace & Sharpen Your Husqvarna Mower Blades.

The Husqvarna Motor Is Being Overworked

You can get the most out of your Husqvarna by first taking stock of the conditions under which you will be doing most of your mowing.

Grass that is too long, too thick, or too damp to cut can place a strain on the engine. It could overheat if you do that.

The solution is to reduce the ground speed of the mower whenever you encounter long, thick, or damp grass. To ease the strain on the motor and get a clean shave, use these strategies:

  • Do not attempt to trim wet grass.
  • If the grass is particularly long, cut it twice or even three times. A part of this procedure involves raising the mower’s deck to its maximum possible position. Proceed with the initial incision. After that, you can make a second cut when the deck is a little lower.
  • Mow the lawn quickly, using the mower’s full throttle.
  • When mowing tall, dense, or wet grass, slow down.

After mowing the lawn, let the Husqvarna engine cool down.

After using a Husqvarna lawn mower, you should wait for the engine to cool down before putting it away.

Mowers from Husqvarna are designed to be used outside. Raise the cowling on your Husqvarna riding mower to reveal the engine.

The mower should run with no obstructions. Your engine will begin to cool down as a natural result of the cooling process.

In this article, Lawn Mower Engine Cooling Times Explained, we go into detail about how long it takes for an engine to cool down and what elements play a role in this.

Is Your Husqvarna Lawnmower Still Giving You Trouble?

I’ve written a guide to the most common issues that Husqvarna mower owners face, so feel free to take a look if you’re still experiencing trouble. I made a list of issues and how to fix them, such as beginning, smoking, cutting, vibrating, and dying.

If you have a Husqvarna lawn mower and you’re not confident in your ability to troubleshoot and fix it, you should probably take it in for service at a nearby Husqvarna dealership or lawn mower repair shop.

To prevent harm or extra damage to the mower, you should only do repairs that are within your mechanical abilities and stay within your comfort zone.