How to Service a Husqvarna Zero Turn Lawn Mower: Step-By-Step

In addition to routine maintenance that must be performed throughout the mowing season, it is necessary to complete a full service to keep your zero-turn running at its best.

Skipping this service can shorten the life of your mower. Not changing the fluids, and filters and performing this service can result in significant costly problems.

Service a Husqvarna zero turn by changing the engine oil and filter; replacing the air filter, fuel filter, and spark plug; cleaning around the engine and transmission; changing the transmission oil and filter if required; scraping the mower deck; sharpening the blades; greasing the mower and more.

Keep reading for additional items to complete when performing maintenance on your Husqvarna zero turn. If you choose to have your dealership perform your annual maintenance, plan on about 2 hours of labor plus the cost of parts. If the mechanic must perform additional repairs, the expense will be greater of course.

Keep safe by following all safety instructions found in your operator’s manual. If you are unsure about completing any of the steps, consult your dealership or have an experienced mechanic perform the work.

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Follow all safety instructions provided in your equipment operator’s manual prior to diagnosing, repairing, or operating.Consult a professional if you don’t have the skills, or knowledge or are not in the condition to perform the repair safely.

Checklist to Service a Husqvarna Zero Turn Mower

A Husqvarna zero-turn mower should be serviced annually. Refer to your operator’s manual for hourly intervals for specific service items.

• Check the safety systems
• Check the starting system & battery
• Change engine oil and filter
• Check transmission oil level. Change transmission oil and filter if necessary.
• Replace spark plug
• Replace the fuel filter and inspect the fuel lines
• Check tire pressures & lug nuts
• Clean or replace the air filter if necessary
• Remove dirt and debris from exhaust, engine, and transmission systems
• Sharpen or change mower blades
• Scrape the deck
• Check the condition of belts and pulleys
• Lubricate the zero-turn and mower deck

Steps to Service a Husqvarna Zero Turn Mower

Collect Tools & Supplies to Service a Husqvarna Zero Turn

It is best to get all of the materials together before you start servicing your zero-turn.

• Engine Oil and Filter
• Transmission Oil and Filter, if needed. Some residential zero turns have sealed transmission systems and are unserviceable.
• Air Filter
• Fuel Filter
• Spark Plugs
• Socket or Spanner Wrenches
• Drain Pan
• Funnel
• Filter Wrench
• Rags, Work Gloves, Safety Glasses, Work Surface Cover
• Deck Scraper, Wire Brush, or Metal Putty Knife

Check the Husqvarna Zero Turn Safety System

Refer to your Husqvarna operating manual for all the safety features provided on your zero-turn. Make sure they are operating correctly.

This includes making sure the mower will not start with the mower deck engaged, without the brake set, and without levers in the open/outward position.

The operator’s presence control system must also be tested to ensure the mower shuts off when the mower deck is engaged and the operator is not in the seat or the parking brake is not engaged when the operator leaves the seat.

Go through all Husqvarna safety features and ensure they are working like they are designed to. Also, take time to inspect the rollover protection system (ROPS) and seat belt to make sure they have not been compromised and are in good working order.

The ROPS system and the seat belt are designed to work together.

Zero-turn lawn mowers are dangerous. Keeping the safety system in good working order can reduce your risks. Read “Dangers of Zero Turn Mower & How to Operate Safely” to make sure you are following the correct safety procedures.

Check the Battery on Your Husqvarna Zero Turn

A Husqvarna zero turn uses a 12-volt lawn and garden battery. Check the battery voltage using a voltmeter. If your battery reading is 12.6 volts or greater your battery is 100% charged. When the voltage reading is less than this, you need to charge your battery.

Make sure all cables are tight. Clean or replace the terminals if they are corroded. Create a baking soda bath using 3 cups of water and 2 heaping teaspoons of baking soda. Using this mixture and a wire brush clean the terminals until the corrosion is removed. Add a dielectric grease to prevent corrosion.

Charge a Husqvarna Zero Turn Battery

• Disconnect the battery cables from the battery. Remember: Positive cable (Red +) is the last one off and the first one on. Now, if the battery has removable caps check the water level. If the plates inside the battery are not covered with water you will need to add distilled water to them. Note: well water is not good for a battery. City water is a little better option, but it is best to use distilled water for your battery.
• After checking the water level, hook the charger to the battery.
• Check the battery voltage with your meter and see what it has in it. If the battery has 11.8 volts in it you won’t have to charge it very long. If it has 10.1 volts your battery is going to need to sit on a charger for a while. The lower the voltage reading, the longer your battery will need to sit on the charger.

  I like to put a very low battery on what is called a “slow bake”. Some battery chargers have different switches on them such as 6 amps, 4 amps, or 2 amps. Charge a very low battery on 2 or 4 amps and let it charge for about an hour.

  After an hour, check the reading to make sure the voltage rate is increasing. If it is, continue to charge for another hour. If it is not increasing it’s time to purchase a new battery. You can find a battery at your local lawn mower dealership, hardware store, automotive parts store, or on Amazon.

Change Engine Oil and Filter on a Husqvarna Zero Turn Mower

Your Husqvarna engine oil and filter on most residential zero turns should be changed every 50 hours or annually to keep your engine lubricated with clean oil.

Commercial zero-turn engines should be changed every 100 hours or annually. Refer to your manual to determine what type of engine you have along with the oil change intervals.

Not changing your engine oil regularly can have damaging effects on the engine. Note: If your engine is new, you need to change the oil after the initial 5-10 hours.

• Prepare Work Surface: Lay covering over your work surface to prevent spilled oil from penetrating the ground. Cardboard and newspaper work well.
• Warm Engine Oil: Start your zero-turn, park it on top of the work surface cover, and let it run for 2 to 3 minutes to warm the engine oil. Warm oil flows better than cool oil. Take caution when working around the hot engine.
• Remove the Key & Unplug the Spark Plug Boot: Remove the ignition key and spark plug boot(s) to keep your mower from starting while servicing your zero-turn. This is a necessary safety precaution to prevent serious injury.
• Remove Engine Oil Plug: Clean dirt and debris from the area around the oil plug or oil drain hose (depending on your model mower) so you don’t contaminate the engine when removing the oil plug. Place a drain pan under the oil plug, remove the plug and allow the oil to drain into the pan.
• Replace Engine Oil Filter & Oil Plug: Clean around the oil filter. Using a filter wrench, remove the oil filter and replace it with a new filter. Place a light film of fresh oil on the gasket of the new filter and place it on the engine. Once all of the oil has drained, reinstall the drain plug.
• Fill with Engine Oil: Fill the crankcase with the quantity and type of engine oil recommended by your manufacturer. You must make sure you have a sufficient engine oil level. It cannot be too low or too high as either level can cause damage.
• Start Engine and Check Oil Level: Reinstall the spark plug boots and start your engine for a few minutes. Turn the engine off and let the oil cool. Recheck the oil fluid level. Add more oil if needed.

Change Transmission Oil and Filter if Necessary in Your Husqvarna Zero Turn

Operating your Husqvarna zero turn with low or old transmission fluid can cause your mower to seem weak when moving. It can also cause extensive damage to the transmission.

Some residential Husqvarna zero turns have maintenance-free transmissions meaning they do not need to be serviced or checked for correct fluid levels. If you find a leak with a maintenance-free transmission, contact your local Husqvarna dealership for assistance.

If you don’t have a maintenance-free transmission, most Husqvarna zero turns with serviceable transmissions must change the transmission oil every 400 hours. Some systems require an initial fluid and filter change after a “break-in” period.

Refer to the operator’s manual for the oil change interval required for your model as it varies with the type of hydraulic fluid used.

For example, Parker recommends using Parker HT-1000 oil for their transmissions while Hydro-Gear recommends 20W-50 engine oil. There are other types of oil that can be used which impacts how often you have to change the fluid and filters.

If you don’t require a full transmission oil and filter change at this time, check your oil level and top off with transmission fuel if needed. You will find overflow reservoirs on top of the mower and behind the seat. There will be two containers.

One for the right transmission and one for the left transmission. The oil level must reach the “full cold” line on the expansion reservoirs.

Refer to your Husqvarna operator’s manual for the correct procedures for changing your transmission oil as it can vary with each model. Air must be removed from the system after an oil change.

Here are the most common directions for changing the transmission oil on a Husqvarna zero-turn lawn mower:

• Park Zero Turn on Flat Surface: Remove the key and engage the parking brake. Wait for all moving parts to stop before working on your zero-turn. Note the engine and transmission can be hot. Take caution when working. 
• Locate Filters & Remove Guards: You will find a filter located near each rear wheel. There may be a guard or skid plate over the filter. Remove the guard and clean around the filters before removing them. 

  Don’t skip cleaning around the filters. You do not want to introduce any dirt or other foreign materials into the transmission system. 

• Remove Filters & Drain: Place an oil pan under one of the transmission filters. Unscrew the filter and let the oil drain. Repeat with the other transmission filter. Remove the drain pan and plan on bringing the old oil to your closest recycling center.
• Install New Filters: Apply a thin layer of fresh transmission oil on the rubber seal of the new filters. Install the filters by turning clockwise. Once the filter makes a good connection to the filter adapter, continue to turn about another full turn. 
• Fill with Recommended Transmission Oil: Locate the expansion reservoirs. These are the little small plastic tanks on the top of your mower behind the seat. Clean around the reservoirs before you remove the caps. Fill with a good quality hydraulic oil adding oil through the expansion reservoirs until it reaches the “full cold” line on the tanks. You will have two tanks, one on each side of the mower.

  Some transaxles will have a vent plug located on each transaxle. Loosen this plug on each side. You will fill the transmission oil through the expansion reservoir until oil comes out of the vent plug. Tighten the vent plugs and continue fulling until the oil level reaches the “cold full” line on the expansion reservoir.

• Purge Air Out of the Transmission System: It’s important to get all the air out of the system by going through some steps with the drive tires turning freely. In order to allow the drive wheels to turn freely, you will need to get the rear wheels off the ground. Do this by using jack stands to raise the rear of the mower just high enough so the wheels no longer touch the ground. 

  Open the bypass valve, start your mower and increase the throttle to about ½ throttle. Release the parking brake. Move the speed levers forward and reverse slowly about 6 times. Repeat this process again with the bypass valve closed until your wheels begin to rotate at a normal rate and with a normal sound.

Let the transmission system cool and re-check your oil level. Add more oil if needed.

Replace Your Husqvarna Zero Turn Spark Plugs

I prefer to replace the spark plugs annually. They are an essential part to start and keep your mower running at its best and they are not that expensive. Remove your spark plug with a socket wrench, and install the new spark plug with the correct gap.

If you choose to reuse your spark plug, you can do so if it is not too dark in color or has a burnt electrode or cracked porcelain. Before you place it back into your zero-turn, use a wire brush to clean the carbon buildup. Check for a correct gap using a feeler gauge.

Do not reattach the spark plug wires until you have completed servicing your Husqvarna zero turn.

Replace the Fuel Filter & Inspect Fuel System on Your Husqvarna Zero Turn

Take this time to check the fuel components for leaks. Follow the fuel lines out of the fuel tank and check the lines, fuel pump, and carburetor for leaks.

Replace the fuel lines if they are dry, cracked, or leaking. The fuel pump must also be replaced if you find it leaking. Replace any dry and cracked fuel lines to avoid potential leaks.

A leak coming from your carburetor can, most likely, be fixed by replacing the gasket or cleaning and fixing its components. Follow these instructions to stop the leak on the carburetor. Once you are done checking the fuel system, move on to replacing the fuel filter.

Old gasoline can cause the fuel filter to degrade if it isn’t changed regularly. It can also become plugged by running old and dirty fuel restricting the fuel flow. The filter is essential to keep contaminants from running through the fuel system.

Replace the fuel filter annually. Install the fuel filter with the arrow, found on the side of the filter, pointed in the direction of the fuel flow. This means the filter must be installed so the arrow is pointed toward the carburetor and away from the fuel tank.

Check the Tire Pressures & Lug Nuts on Your Husqvarna Zero Turn

Make sure your lug nuts are tight and your drive tire pressures are equal on each side. They should be filled at Husqvarna’s recommended tire pressure for your model zero turn.

Uneven tire pressures can cause uneven cutting conditions. It can also cause your mower to pull one way causing your mower not to move in a straight path.

Replace a Husqvarna Zero Turn Air Filter

Your engine requires clean air to operate efficiently. Without access to clean air, your engine is starved of air, will run sluggish, and possibly overheat. Replace your air filter annually. Remove your old air filter from the air filter housing. Be careful not to knock any dirt into the air intake.

Remove any dirt you find in the housing with a dry clean cloth. Install the new Husqvarna air filter and reattach the cover.

Maintenance on your air filter doesn’t stop here. You need to check and clean it several times throughout the season. You can find instructions for cleaning your air filter here.

Remove Dirt and Debris from Exhaust, Engine and Transmission Systems on Your Husqvarna Zero Turn

Keeping the air pathways open so air can circulate around the engine and transmission to keep them cool is essential. Buildup around the engine cooling fins, the engine block, and engine covers can cause your Husqvarna to overheat and shut down.

Remove this debris and dirt from these areas and the areas around the transmission including the hydro fan cooling fins and guards.

Check Condition of Your Husqvarna Zero Turn Belts, Pulleys & Spindle Housings

Take time to check over your Husqvarna zero-turn’s mower deck components. Some Husqvarna zero turns will have a removable floor pan to easily access the top of the mower deck.

If your model doesn’t have an easy way to access the top of the deck to check your belts and pulleys, you must remove it.

Again, confirm the spark plug wires are disconnected. Worn belts and pulleys can cause your transmission pump or mower blades not to work properly. If your belts appear worn, cracked or have a glazed appearance to them, you need to replace them.

Over time, bearings can wear and become damaged. To check the bearings in your pulleys, slowly turn each pulley to ensure they are still moving freely and you don’t feel any resistance.

While turning the pulley, listen for any noise coming from your bearing. Replace the pulley if you hear noise or feel resistance. A good pulley must also sit level and parallel to the mower deck.

Check for bearing wear in your spindle housing. Do this by grabbing a hold of each side of the mower blade while wearing a good pair of work gloves to protect your hands from sharp edges.

Rock the blade with an up-and-down motion. If you feel movement, you need to replace the bearing or spindle housing assembly.

Scrape the Mower Deck on Your Husqvarna Zero Turn Mower

Safely gain access to the underside of your zero-turn mower deck by using jack stands or one of these handy lifts from Amazon. Keeping the mower deck clean will provide you with a better cut and better mower performance.

Buildup underneath the deck compromises the air movement needed to create a good cut. The mower blade is designed to create air movement in the deck.

The blade along with the suction created in the mower deck makes the grass blade stand tall so the blade can pass by and precisely cut the grass blade.

Scrape the deck using a deck scraper or metal putty knife each time you service your zero-turn mower deck. A good stiff wire brush also works well.

This is something you will want to do throughout the mowing season so the mower gives you a good cut performance. Avoid mowing grass when it is damp or wet to reduce the amount of grass sticking to the deck.

Sharpen or Change the Mower Blades on Your Husqvarna Zero Turn Lawn Mower

I like to replace my mower blades annually with new mower blades and sharpen my old set to keep on hand. I like to have a spare set in case I damage a set of blades. This will prevent significant downtime while I wait for a new set of blades.

Keeping your Husqvarna blades sharp will help you achieve a good cut with your zero-turn. Remove and replace with new blades or with sharpened blades if you choose to reuse your current blades.

You must replace your blades if you find damage including gouges and bends. If the sails of your blades are worn or the ends are rounded, it’s best to use new blades.

Read more about inspecting and sharpening your blades in “How to Change & Sharpen Your Husqvarna Mower Blades“. I include information on balancing your blades so you don’t incur damage to the spindles, vibration in the mower, and an uneven cut.

Lubricate the Husqvarna Zero Turn and Mower Deck

Using a high-performance multi-purpose grease, lubricate the front caster wheel mount. The grease zerk can be found on the outside of the mount or under the dust caps. Lubricate the front wheel bearings. You will also need to lubricate the deck spindles.

Refer to your operator’s manual to verify all grease points on your zero-turn model. Wipe off any extra grease.

You do not want grease getting on your belt or around the grooves of your pulleys. Grease on the belt will cause it to slip and you’ll have to purchase a new belt.

How Often Should You Service a Husqvarna Zero Turn Lawn Mower?

A Husqvarna zero-turn mower needs to be serviced every 50 hours or annually. Husqvarna zero turns running commercial engines should be serviced every 100 hours or annually. Refer to your operator’s manual for specific service intervals for the engine in your model Husqvarna.

In between these full services, the engine, transmission, and deck must be kept clean and free of debris and the Husqvarna must be properly lubricated.

You must also check for sufficient engine and hydraulic oil levels; good tire pressures; a working safety system; damage and loose parts prior to operating.

Added Steps to Winterize Your Husqvarna Zero Turn Lawn Mower

While many of the steps remain the same when getting your mower ready for winter storage, it is important to prepare your zero-turn’s fuel system. You will also need to make sure your battery is properly cared for so it does not freeze over the winter.

Read more about winterizing your zero turn in this guide.

Having Problems with Your Husqvarna Zero Turn?

You are likely to develop problems sometime during the life of your mower. There isn’t a trouble-free mower on the market. To help you determine the cause of zero-turn mower problem, I put together this guide, “Common Husqvarna Lawn Mower Problems and Solutions “.