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How to Store Your Mower For Winter

How to Store ​​​a Zero Turn Lawn Mower for Winter​​

Easy winter lawn mower ​​​maintenance​

Storing your outdoor power equipment correctly is extremely critical for anything with an engine. If avoided, you risk serious mechanical and or performance issues when it's time to use the machine next spring. To help ensure your mower starts and performs its best, we compiled a list of must-do winter storage procedures. Before you start any of these procedures on your own, refresh your knowledge on important safety practices and procedural instructions in the operator's manual for your unit.

1. Stabilize lawn mower fuel

If anything tops the list in terms of storage importance, it's stabilizing your fuel. At Gravely, the most common maintenance issues we learn about are those related to deteriorated fuel that clogs the fuel system.

Gasoline breaks down in as little as two weeks, let alone the two or three months it spends sitting in a fuel tank during seasonal storage. When fuel deteriorates, it turns to a gel-like substance, clogs your fuel system and prevents your engine from starting or running. Not only does this cost downtime, it leads to unserved clients and repair bills.

Fuel blends with an ethanol content of 10% or less is technically acceptable in small engines, including those that power Gravely lawn mowers, but ethanol's characteristics increase the potential for fuel-related issues in small engines.​​ Ethanol is a solvent and can dissolve varnish buildup in older engines, and when that varnish breaks loose, those deposits travel through the fuel system and clog it.

To help avoid small engine problems because of fuel issues, Gravely recommends treating your fuel with a quality fuel stabilizer. If you've never done this before, it's simple, but it's critical to follow the instructions exactly as they're outlined below to ensure effective results. Without following these instructions closely, your efforts may not be as effective.  Also, know that fuel cannot be rejuvenated. If the fuel in your mower tank was pumped fresh more than two weeks ago, either drain it and dispose of it responsibly, or use it up now. Even so, it's best to then add fresh fuel to the tank or tanks, even if it was drained, and then stabilize according to the instructions below because residue from that old fuel can still clog a fuel system. Remember, in carbureted engines, fuel needs to fit through the tiny hole in the carburetor jet, and it only takes one drop of bad fuel to clog it.

Carburetor jet clog

How to stabilize gasoline:​​

  1. If your mower has fresh fuel (gasoline purchased less than two weeks ago), estimate how much fuel is in the tank. You will need to know that quantity to correctly calculate the amount of fuel stabilizer needed.
  2. Add fuel stabilizer to the fuel tank (or tanks) according to the instructions on the fuel stabilizer packet or bottle.
  3. Start the engine and operate the mower for about ten minutes to incorporate the stabilizer throughout the fuel system.
  4. If the mower has a carbureted engine, keep the engine running, close the fuel valve and allow the engine to stop on its own. If it's an EFI engine, simply switch the key to the off position and remove it.
  5. After the engine stops, turn the key to the off position and remove the key.

To find fuel stabilizer, visit your nearest Gravely dealer​ or purchase it online here.​


2. Change lawn mower oil

Oil changes are easy to perform​ and they don’t take much time. The engine is your power plant and it needs to be protected so it can continue to perform well and reliably. After a full season of use, your engine needs an oil change and a new oil filter. Though performing an oil change isn't absolutely necessary before storing outdoor power equipment, it removes a step that would otherwise need to be done at the beginning of the next mowing season​. It won't hurt anything if you don't do it before storage, but it's best practice to finish it so it's not forgotten.

Lawn mower oil change instructions:​

​​​​​A brief outline for engine oil changes are listed below. For the full oil change details, reference the instructions in the engine manual for your unit. And as always, refer to the safety instructions in the operator's manual for your unit before attempting service procedures on your own.

  1. Remove the drain plug and allow oil to drain into a container. Use a funnel if necessary.
  2. Once drained, reinstall the drain plug and tighten to the specification in the manual.
  3. Remove the oil filter, allow the oil to drain from the filter and into a container and dispose the filter.
  4. Dip the tip of your finger in the used oil and apply a thin layer of oil around the rubber gasket of the new oil filter.
  5. Install the new oil filter and tighten according to the specifications in the manual.
  6. Remove the cover from the engine fill port and add the correct volume and type of engine oil listed in the manual.
  7. Reinstall the fill port cover.
  8. With the parking brake on, start the mower and visually inspect the engine to ensure oil isn't leaking. Stop the engine when you confirm oil isn't leaking from the drain plug or around the filter.

3. When to change a lawn mower air filter

Dust, dirt and other debris sucked in through an engine’s air intake can damage the engine, which is why each engine has an air filter. As the engine ‘inhales,’ the filter catches debris and prevents it from entering the engine and harming its delicate components.

Even the smallest airborne particles can damage an engine. And while the engine air filter does its job catching these particles, it collects so much debris over time that it becomes full and less effective. Additionally, a dirty air filter's restricted airflow makes an engine work harder and reduces its efficiency. This is why it’s important to check the filter regularly and replace it when needed.

Engine air filter replacements are not necessary to complete before seasonal storage, but once again, do it now so it's not forgotten later. It could make a big difference in your fuel consumption at each job.

4. Change hydro oil

Like engine oil, transmission fluid needs to be changed annually or at the intervals listed in your manual. Though there's no combustion inside a transaxle, the mechanics inside the unit create friction and heat, which degrades the oil. Commercial lawn mowers that are operating as much as 12 hours per day absolutely must have their transaxle oil changed multiple times throughout the mowing season – or however often as outlined in your unit's operator's manual.

Now that you're at the end of the busy season, chances are it's time to change it:

  1. Operate the unit for a few minutes to warm the fluid.
  2. Stop the unit and wait for hot parts to cool.
  3. Remove the transaxle filter guards, if equipped.
  4. Remove oil filters, drain filters and dispose.
  5. Remove the fill plugs from transaxles.
  6. Wipe the filter mounting surfaces clean.
  7. Lubricate rubber gasket on new oil filters with hydraulic oil.
  8. Install filters onto transaxles and torque to specification.
  9. Reinstall filter guards with original hardware and torque to specification.
  10. Add the correct type of hydraulic oil to the transaxles until oil appears at the bottom of the oil fill openings.
  11. Reinstall oil fill plugs and torque to specification.
  12. Add hydraulic oil to the expansion tanks until fluid level meets the cold fill line.
  13. Purge the hydraulic system according to instructions in manual.

5. Connect battery charger

Seasonal battery storage is important. If you own a motorcycle or other seasonal recreational equipment, you might be familiar with this procedure. When not used for extended periods, batteries in cars, recreational and outdoor power equipment can discharge and lose their charge capacity. To keep your battery in good health for next season, disconnect its cables from the terminals and connect it to battery tender or trickle charger.

Battery tenders are a little different from trickle chargers. A trickle charger applies a constant, weak charge to the battery and keeps it fully charged through the offseason. Battery tenders charge a battery, stop charging once the battery reaches a full charge, and then start charging again when the battery drops below a certain voltage.

Both options are good solutions for maintaining a mower's battery health, but some resources suggest a battery tender is the better option because the constant charge from a trickle charger can damage the battery.

6. How to clean the lawn mower deck

Cleaning has a purpose. Grass and debris buildup under the deck and around the spindles can affect the mower's performance, cut quality, and your reputation as a landscape professional. Additionally, grass and debris buildup retain​ moisture that can rust and corrode critical mower deck components, which is why it's important to periodically remove the deck and clean it.

Removing a Gravely lawn mower deck is easy. We include detailed instructions in the operator's manual, but it's as simple as:

  1. Remove the PTO belt from around the clutch.
  2. Disconnect the deck lift linkages.
  3. Disconnect the deck mounting arms.
  4. Remove the deck from under the unit.
  5. Carefully remove the blades.
  6. Clean the debris from under the deck with low-pressure water. Using high-pressure water can damage certain components.

If you see rust forming on bare metal areas under your deck, remove it with an abrasive tool like sandpaper, clean the area and cover it with touch-up paint.

C​​lick here to watch how to remove a Gravely deck. 

Check mower belts and blades

It’s not critical for storage maintenance, but as long as the deck is removed, it's an opportunity to check blade condition and to sharpen according to the instructions in your operator's manual. If blades are damaged or worn too much, replace them. Also, check your belts for signs of wear and replace if necessary. Remember, if you do it now, you get a much faster start on your next season.

Remove lawn mower blades

Replacement Gravely commercial lawn mower parts

Our objective to providing a comprehensive checklist for seasonal maintenance is to help keep your Gravely mower running as good as the first time you used it. Gravely commercial lawn mowers are designed to live up to expectations, which is why we supply your local Gravely dealer​ with genuine Gravely OEM parts and accessories.

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