John Deere Zero-Turn Mower Preventive Maintenance Tips

Whether for your home or business, zero-turn mowers (ZTRs) can improve your mowing efficiency, helping you do the job correctly and quickly. They’re particularly helpful in maintaining big plots of land.  

ZTRs are among the most essential tools for professional landscapers and homeowners alike.  

They’re also an investment. So, when you buy one, you want to take care of it.  

Like any other machine, a good preventative maintenance program can be the difference between reliable, hassle-free equipment and machines that aren’t ready to go when you are.  

At RDO Equipment Co., we sell and service John Deere zero-turn mowers in more than 15 stores across the U.S., including Minnesota, North Dakota, Montana and California. 

We’ve outlined tips for maintaining your zero-turn mower to help you get the most out of your investment. 

Zero-Turn Mower At-Home Maintenance Tasks 

Zero-turn mowers' preventative maintenance is similar to that of other commercial lawn mowers. However, there are also a few unique tasks you should plan for. 
 
Before performing any maintenance, consult the operator’s manual, wear appropriate safety gear, park the mower on a flat surface and ensure the engine is off and cool. 

After that, here are five things you should do for your mower on a regular basis — at least once per year or after 50 hours of use. 

1. Examine and Replace the Air Filter 

A clean air filter can be a game-changer in a ZTR’s performance. Dirty air filters often contribute to inefficient operation. They can result in wasted fuel.  

Perhaps most concerning, a dirty filter cannot do its job. If it allows dirt and other debris to enter the engine, the result can be permanent damage. 
 
Professionals should check the air filter at least weekly to assess its condition. 

For homeowners, checking a couple of times per year, particularly after heavy use, will do the trick.  

Those who work in dry, dusty or dirty conditions may want to do this step more frequently, as will people at the height of their busy season. 
 
When evaluating how long your air filter will last, consider seasonality.  

Fall, in particular, can be a drier time of year. Tasks like bagging leaves put greater stress on the filter. During these peak times, it is common for professionals to check the air filter weekly or even daily.  

Caring for Your Zero-Turn Mowers' Air Filter 

When it is time to change the air filter (or filters, some ZTRs have dual elements), clear away any debris from the air intake area first.  

A paper air filter can be gently tapped to remove excess debris, but never blow air on or attempt to clean a paper air filter.  

Instead, change the air filter as needed. Insert a new, clean air filter, and ensure no debris enters the engine. 

2. Examine and Replace the Fuel Filter and Stabilizer 

The fuel filters and air filters do similar jobs. Clean fuel filters keep harmful particles from entering and damaging the engine. They also aid in efficient fuel consumption. The best time to change a fuel filter varies by ZTR.  

Use the operator’s manual as a guide, then check regularly, as appropriate. 
 
Another factor affecting filter changes' timing is how much fuel is consumed, or how much the mower runs.  

For companies or individuals who put a lot of hours on their ZTRs, the fuel filter may need to be changed often.  

It might not need as frequent attention for fleets with other mowers sharing the workload, or homeowners who do not mow as often as commercial users. 

Caring for Your Zero-Turn Mowers' Fuel Filter 

When changing a fuel filter, begin by placing a drain pan under it.  

Pay attention to the arrow on the existing fuel filter and its direction. The new filter must be attached so the arrow points in the same direction. 

Inspect the fuel filter and connecting hoses, looking for cracks or signs of excessive wear.  

Next, loosen the hose clamps and move them away from the filter. 

Disconnect the hoses from the old filter, then quickly reattach the new one, ensuring it faces the correct direction.  

Finally, reposition the hose clamps to ensure the filter is secure. Start the mower and let the engine run for a few minutes while checking for leaks. 
 
Don’t forget to dispose of your old filter in an environmentally responsible way. Most filters need to drain for a day, then disposal will vary according to local laws. Any spilled fuel and fuel-soaked towels should be discarded properly. 
 
Adding fuel stabilizer at certain times during the year is a good practice.  

For cold-weather climates, stabilizer is common just ahead of winter months, in prep for your mower to sit idle for more extended periods. This practice is also smart for hot-weather climates, as stabilizer can prevent fuel from going bad anytime the mower is expected to not run for a while. 

3. Change Engine Oil 

A staple of any equipment preventative maintenance is a weekly (or even daily) oil check. 

While crucial for all users, this step will vary depending on whether you use your ZTR as a homeowner or for commercial purposes. 
A homeowner usually needs to change their mower engine oil annually.  

Professionals should check and change their ZTR’s oil more often. The environment is a leading factor in how frequently oil changes are required.  

Like with the air filter, dry, dusty, and dirty conditions will mean more frequent changes. 

How to Change the Engine Oil on Your Zero Turn Mower 

An oil change is quick and easy for most equipment owners and operators. However, for those who are newer to the process or need a simple refresher, here is a quick step-by-step for changing engine oil. 
 
First, place a drain pan under the oil plug, along with a few towels near the filter, and loosen the dipstick. Next, drain the oil. Many ZTRs have quick-drain valves.  

Remove the oil filter and install a new one, making sure to get it tight. 

Replace the oil plug, then wipe down and clean the area. Give the engine a fresh oil fill, then replace the dipstick. 

There are a few final to-dos before this job can be checked off the list.  

First, run the engine for a minute, then shut it off and allow ample cool-down time.  

While the engine is cooling off, clean any spilled oil. Collect the old oil and any oil-soaked towels, then dispose of them properly. Check with local regulations and, ideally, look for recycling options. 

After the engine has cooled to a safe working temperature, check the oil level again. Overfilling can damage the spark plug and lead to engine start issues. 

4. Maintain the Transmissions 

If you think all lawn mowers, especially commercial-grade mowers, have the same maintenance requirements, you’re not far off.  

However, one thing that sets ZTRs apart from other commercial mowers is their dual transmissions. Take extra care to address the transmissions regularly. 
 
Be diligent about checking the transmission’s filters and oil and changing them when needed. This will be the same process we outlined above. 

5. Miscellaneous Maintenance Tasks 

A zero-turn mower maintenance routine wouldn’t be complete without a few miscellaneous tasks. Some should be done daily, while others can be done less frequently. 
 
Check the ZTR’s tires and tire pressure at the start of each day. This is an important step, as low tire pressure on one side can throw off the transmission and cause the mower to drift or pull to one side.  

Inadequate tire pressure also affects the quality of the cut. Noting a low tire at the start of the day can uncover a bigger problem, like a puncture, that can be taken care of immediately. 
 
Another check to complete when the day begins is of the bagger, if one is being used.  

Like before, fall is an important time to check things more often. Add the bagger to this list.  

Look for rips, holes, or other damage that would warrant replacement.  

Professionals covering a lot of acreage may even want to check the bagger multiple times a day, including after every large job. 
 
When starting up the mower each day, stop for a moment to listen. Every operator, whether veteran or newer, can hear when something does not sound right. This can signal it is time to check the idlers or bearings. 

Three things contribute to good airflow and quality of cut: a clean mower deck, well-maintained belts and sharp blades. 
 
Inspect the mower deck for excess debris to clean at the end of each day. As needed, remove the mower deck as instructed in the owner’s manual and clean the bottom side of the deck. 
 
Inspect the drive belt once a week for worn or cracked areas and replace it if necessary. 
 
Also, remove and check the blade to look for any signs of damage or excessive wear. Depending on the condition, a blade can be replaced or just needs to be sharpened.  

Many professionals find the blade to be one of the most important areas to check, and it will be cleaned and sharpened weekly. 
 
Finally, give the ZTR a quick cleaning at the end of each day. This does not mean a full wash and dry, getting into every nook and cranny, and polishing it up to look shiny and new. Simply blow off the machine with a handheld blower or compressor. Pay extra attention to the transmission area to prevent excess debris buildup. 

Basic maintenance is often overlooked or a “we’ll do that tomorrow,” kind of task, but it is one of the easiest and low-cost ways to invest in a lawn mower. Start with a few minutes each day and these five basic areas to build a preventative maintenance program for your zero-turn mower. 

Extend the Life of Your Zero Turn Mower 

With proper maintenance, you can significantly extend the lifespan of your zero-turn mower.  

Whether you’re a homeowner with acreage to tend or a commercial lawn and landscape professional, there are plenty of tasks you can do to prolong the lifespan of your investment, including: