Husqvarna Riding Mower Loses Power When Blades Are Engaged

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If your Husqvarna riding mower loses power when blades are engaged, it can be really disturbing, especially when you need to carry out some mowing tasks.

In this article, I share 10 common reasons why your Husqvarna riding mower loses power when blades are engaged and troubleshooting steps you can take to diagnose and fix these issues. 

Reasons Why Your Husqvarna Riding Mower Loses Power When Blades Are Engaged

Some of the reasons why your zero-turn may lose power when blades are engaged may include:

  • Bad gas
  • Worn out blade spindle bearings
  • Dirty underside
  • Dull blade
  • Dirty carburetor
  • Bad spark plug
  • Loose/worn transmission drive belt

Tools You May Need for This Job

  • Wooden blocks
  • Protective gloves.
  • Socket Wrench

Husqvarna riding mower Loses Power When Blades Are Engaged: Possible Causes and Fixes

1.  Dull Blade

When the blade is dull, it has to work harder to mow through the grass which can cause the mower engine to lose power when blades are engaged. 

This will further affect the functionality and performance of your Husqvarna riding mower.


  • Inspect the blades to see if they are dull.  


How To Replace Blades on a Husqvarna Riding Lawn Mower


Here are some tips on how to replace the mower blades on your Husqvarna riding lawn mower:

Step One: Inspect the Condition of the Blade

The first step to take is to know the condition of your blades by checking the blades or grass. Quality mower blades will be able to mow your grass evenly and cleanly.

Usually, the same grass length should be mowed with each mower’s pass if the mower height isn’t changed.

The factors for checking the blade’s condition include the quality of the blade surface, blade sharpness, dent/twist and cutting edge thickness.

Ensure that you check the blade of your Husqvarna mowing machine before or after every mowing session.

Step Two: Gather the Required Tools

Make sure that you gather tools like protective gloves, wooden blocks and a socket wrench.


Step Three: Park Your Mowing Machine in a Flat Area

Ensure that you park your mowing machine in a flat area. The parking brake should be engaged but make sure that you keep it in gear for now. Position your mowing deck to its highest setting.

Step Four: Disconnect Your Spark Plugs

It is advisable to disconnect the spark plugs for safety purposes. This will also prevent the engine from running while working on your riding mower.

Do not pull your spark plug cable rigorously. Instead, grasp the lead where it attaches to the plug and twist it from side to side until it can move freely. 

Make sure that you pull it to the backward position gently.

Step Five: Take Off Excess Gas From the Tank

Make sure that you take off excess gasoline from your tank to prevent spillage when tilting the mowing machine. You can also make use of a siphon to remove the excess gas.

Step Six: Lift or Tilt Your Husqvarna Riding Mower

You need to lift or tilt your mowing machine to have access to the mower blades. 

Make sure that the mowing machine is stable after tilting it and ensure that there is enough support to prevent it from falling back when working on the mower.

Use a lawn mower lift to lift your Husqvarna riding lawn mower.

Step Seven: Take Off the Bolt

It is advisable to wear protective gloves when dealing with a sharp mower blade. Lay on your back close to the mowing machine.

To lock the blade, place a block of wood underneath the mower deck. This will prevent it from turning when you try to loosen your nut. 

If you can’t lock it, you can also hold the mower blade with your protective gloves.

Loosen the bolt holding the blade to the spindle by rotating it until it makes contact with the block. Ensure that you hold it firmly with your hand.

To take off the bolt, the wrench should be rotated clockwise. You can also remove any washer that is positioned at the spindle.

Step Eight: Detach The Mower Blade

The blade is free for removal when the washer and bolt are off. Take off the old blade and bring out the new mower blade.

Step Nine: Install Your New Husqvarna Riding Mower Blade

Install your new mower blade on the spindle. To ensure that it is locked correctly, make sure that the star pattern on the blade is in line with the star pattern of the spindle. 

Place your washer on the mower’s spindle and its bolt and then tighten it (bolt). Make sure that the wrench is turned counterclockwise.

Always note that the curved side of your new mower blade should always point up. To get more information, you may need to check the manufacturer’s manual or consult the blade’s supplier.

Make sure that the bolt is tightened and locked correctly. Without touching the boundary of the cutting area, the blade should rotate freely.

Repeat the same procedure if your Husqvarna riding lawn mower comes with two blades. To make it easier, you might want to tilt the mowing machine in a different direction. 

2. Worn Out Blade Spindle Bearings

Worn-out blade spindle bearings can be a reason why your Husqvarna riding mower may lose power when blades are engaged. 

The bearings enable the blades to freely spin on their axis. If it is worn out, it can cause friction and may make your mowing machine lose power.


  • Examine if the blades can freely spin on their axis. If not, it means that the bearings in the blade spindles are worn out.


  • Replace worn-out blade spindle bearings.

3. Clogged Muffler

The function of the muffler is to expel the burned gas and other vapors. If it is blocked by grass, dirt and other debris, it can cause your mower to lose power.


  • Check the muffler for debris, dirt and other fluids.
  • If you notice a colored smoke that comes out of your zero-turn mowing machine, then there is a high chance that the muffler is clogged.


  • Replace the clogged muffler for a new one.

4. Bad Gas

Bad gas is one of the reasons why your Husqvarna riding mower may lose power when the blades are engaged.  

The issue with bad or stale gas is that it is less combustible and can pose an issue when you want to climb a steep hill.


  • Check your gas tank for substances that are left behind by old gas.


  • Drain out the old/bad gas and fill it with a fresh one. 

5. Dirty Carburetor


The carburetor can regulate the right amount of air and gas that should be allowed in the cylinder to form combustion.

Dirt and other substances left behind by old gas can cause the carburetor to be dirty. This will cause the mower to lose power when the blades are engaged.


  • Check the carburetor for dirt and other substances left behind by the old gas.


  • Clean the carburetor or replace it if it is in bad condition.

6. Dirty Underside

A dirty underside might be one of the reasons why your Husqvarna riding mower may lose power when the blades are engaged.

This issue is common with Husqvarna Husqvarna riding mowers. Whenever the blade is engaged, the underside rotates on a crankshaft to mow the grass. 

The mower engine can shut off if there is an interference in this rotation.


  • Inspect the connection of the crankshaft to see if it rotates freely. If the crankshaft’s connection does not rotate freely, it indicates that the mower’s underside is dirty.


  • Clean the blade so that it will be free of debris, dirt and grass. 

7. Loose or Worn Transmission Drive Belt

This is one of the reasons why your Husqvarna riding mower may lose power when the blades are engaged. 

The transmission drive belt may be worn or slightly loose, affecting the transmission of your mower.

In this situation, the deck may cause the transmission to lose power as long as the engine RPMs remain the same.


  • Remove the deck to gain access to the belt and check for wear or looseness.


  • Replace the bad belt with a new one. 

8. Bad Pulleys

The mower belt drives the pulleys, which in turn moves spindles. 

If the pulleys cannot turn freely, they would cause the engine to lose power. This will affect the operation of your Husqvarna riding mower.


  • Check pulleys if they are moving freely. If not, it indicates that the pulleys are bad.


  • Replace the pulley if it is sticky or damaged.

9. Dirty Air Filter

It is also important to check the air filter if your Husqvarna riding mower is losing power. 

The mower engine requires air to run and when it no longer gets the air it requires, the engine may lose power.


  • Take off the air filter from the air filter housing and check for dirt on it


  • Clean or replace the air filter if it is in bad condition.

10. Faulty Spark Plug

For air and gas to be ignited, the mower’s spark plug must be in a good condition and correctly adjusted.

Over time, it may wear out and it will no longer have enough power to ignite gas and air This can make the zero-turn tp lose power when blades are engaged..


  • Use a socket wrench to remove the spark plug.
  • Clean the spark plug with a wire brush.
  • If the firing end is covered with carbon, it means that the spark plug needs to be changed.


  • Replace the faulty spark plug with a new one.


It is important to note that this is one of the most common Husqvarna mower problems. Some factors that may cause your Husqvarna riding mower to lose power when blades are engaged include a defective spark plug, loose or worn transmission drive belt, blocked muffler, dirty underside, and bad gas.

Follow our practical fixes to help solve the issue. If the problem persists, it is best to seek the help of a professional to help you to fix it.