5 frequent John Deere Z930M problems – school me…

Got a Z930M? You might want to sit down for this – we’ve got some sketchy problems we uncovered that can affect you with this mower…

In this guide, we’ll learn you on how we’ve identified and detailed 5 critical problems: engine stalling, hydraulic leaks, an unleveled mower deck, transaxle vibration and noise, and uneven cutting.

Whether you’re mulling over the idea of buying one or already have one parked in your shed, it’s essential to know what you might be up against. This piece is here to help you navigate through the common hiccups that come with owning this model.

  • Engine Stalling: Jake Robbins, a homeowner in Texas, reported this issue. He noticed his Z930M stalling mid-mow. Severity: Medium. Fix: Jake advises checking the fuel lines for blockages and ensuring the fuel filter is clean.
  • Hydraulic Leaks: Susan Kline, who runs a small landscaping business in Ohio, encountered this problem. Severity: High. Fix: Susan recommends inspecting hydraulic lines for damage and replacing them if necessary.
  • Mower Deck Not Level: This issue was brought up by the Green Valley Gardening Club in California. Severity: Medium. Fix: The club suggests adjusting the deck height and ensuring all parts are properly aligned.
  • Transaxle Vibration and Noise: Reported by Dan Murphy, a mechanic from Florida. Severity: High. Fix: Dan’s solution is to check for debris or damage in the transaxle and consider replacing the fluid.
  • Uneven Cutting: A common complaint among various internet users. Severity: Medium. Fix: The online community recommends sharpening or replacing mower blades and ensuring the deck is level.
8 Common John Deere Z930M Problems & Their Fixes

1. Engine Stalling

Known for its 25.5 horsepower and a top speed of 10 mph, often faces engine stalling issues. Jake Robbins, a homeofwner in Texas, reported his Z930M stalling mid-mow, highlighting the medium severity of the problem. He suggests checking fuel lines for blockages and ensuring the fuel filter is clean as a fix.

A common cause for engine stalling is a blocked fuel filter, which can lead to overheating, sputtering, or failure to start. Engine sputtering, often linked to the PTO, can occur if the PTO clutch malfunctions, resulting in power loss. Electrical coil malfunctions, indicated by one side of the plug not firing, can also cause stalling.

Experts from RDO Equipment Co., a licensed John Deere Equipment Dealer in McKinney, TX, advise owners to be proactive in maintaining their mowers. They stress the importance of regular checks of the fuel filter, PTO, and electrical coils to prevent stalling issues​​.

How to Fix Engine Stalling:

  1. Check the fuel filter. If it’s clogged or full of water, replace it immediately!
  2. For engine sputtering, inspect the PTO. If you hear unusual noises, cut the blades to see if it helps. Check the PTO switches for functionality and power.
  3. Examine the quality of the fuel. Bad fuel can hinder engine performance. Replace the oil or gasoline if necessary.
  4. Inspect the air filter. If it’s in poor condition, clean it using a cotton pad.
  5. If you suspect an electrical coil issue, test the coils. Replace any malfunctioning plug and ensure all connections are secure.
  6. Always remember: regular maintenance and timely checks can prevent most issues.
What Majority of the Customers Feel About?

2. Hydraulic Leaks


This model, a highly efficient zero-turn mower with a robust 25.5 horsepower Kawasaki engine and an 11.5-gallon fuel capacity, is known for its hydraulic leak issues. Susan Kline, who operates a small landscaping business in Ohio, has experienced this problem firsthand.

She stresses the severity of these leaks, advising the inspection and replacement of damaged hydraulic lines as necessary. Cracked plugs, a failing seal around the input shaft, and brittle shavings magnet covers are typical causes of these leaks.

Adding to this, a statement from TriGreen Equipment in Oxford, Alabama, a local John Deere dealership, emphasizes the importance of regular maintenance. They advise, “For the longevity of your John Deere equipment, particularly models like the John Deere Z930M, it’s crucial to address hydraulic leaks promptly. Regular checks and timely repairs are key to avoiding major breakdowns”​​.

How to Fix Hydraulic Leaks:

  1. Begin by inspecting the hydraulic lines for any visible damage.
  2. Check the plug covering the shavings magnet—if it’s brittle or cracked, replace it immediately.
  3. Examine the seal around the input shaft. If it appears dry or damaged, it’s time for a replacement.
  4. If you’re unsure about the source of the leak, consider seeking professional guidance. Remember, timely intervention can save you from more significant issues down the line!
  5. Always ensure the mower is turned off and cooled down before starting any repair work—safety first!
  6. Once you’ve identified and fixed the issue, regularly inspect these areas to prevent future leaks.

3. Mower Deck Not Level

The issue of an unlevel mower deck in this mower was highlighted by the Green Valley Gardening Club in California, who rated the severity of the problem as medium. The club suggested adjusting the deck height and ensuring all parts are properly aligned to resolve the issue.

This problem, common in this model, affects its performance and efficiency due to the 25.5HP Kawasaki engine and substantial fuel tank capacity. Uneven tire pressure, misadjusted height settings, and worn or misaligned components are typical causes, leading to uneven cuts and additional strain on both the engine and lawn. An unlevel deck also increases fuel consumption, raises operating costs, and shortens component lifespan due to undue mechanical stress.

Adding to this, a statement from Heritage Tractor, Inc. in Lawrence, Kansas, a licensed John Deere service center, emphasizes the importance of regular maintenance checks: “Regular inspection and alignment of your mower’s deck are crucial to ensure optimal mowing performance and prevent long-term damage to the machine”​​.

How to Fix Mower Deck Not Level:

  1. Park the mower on a level surface and ensure the transmission is in neutral.
  2. Check the tire pressure—uneven pressure can cause deck misalignment.
  3. Locate the mower deck lift handle on the left side of the fender deck. Pull it inward and adjust to the desired cutting height.
  4. If the mower deck gauge wheels touch the ground, adjust them. Remove the 13 mm bolt in the middle of the gauge wheel, slide the wheel up, and then retighten the bolt. Do this for all gauge wheels.
  5. For mechanical adjustments, press down on the left side foot pedal and adjust the mower lift lock lever. Adjust the cutting height knob to the desired height.
  6. Always ensure all parts are properly aligned and tightened—loose components can lead to an unlevel deck.

4. Transaxle Vibration and Noise

The transaxle vibration and noise issue, as reported by Dan Murphy, a mechanic from Florida, is a matter of high severity. He suggests checking for debris or damage in the transaxle and considering fluid replacement as potential solutions. This issue, often caused by debris or damage in the transaxle, fluid problems, or mechanical failures in the hydro system, can be aggravated by mowing on rough and hilly terrains, as in parts of Kentucky.

Some users experience these problems even before the first 300-hour ‘break-in’ hydro filter and fluid change, noticing shimmering fluid and black metal chunks in the filter.

Wright Implement, a licensed John Deere service center in Bardstown, Kentucky, emphasizes the importance of regular maintenance, especially in challenging terrains, to prevent such issues​​.

For fixing this issue, it is essential to inspect the transaxle for visible debris or damage, replace the fluid if necessary, and consult a professional or a local John Deere dealer for a comprehensive solution.

How to Fix Transaxle Vibration and Noise:

  1. First and foremost, check the transaxle for any visible debris or damage.
  2. Consider replacing the fluid, especially if it appears shimmering or if you find metal chunks.
  3. If you notice the mower not tracking straight, especially on slopes, it’s a sign to inspect the transaxle.
  4. If the vibration is visible in the tire while stationary, it’s crucial to address it immediately.
  5. When in doubt, consult with a professional or your local John Deere dealer.

5. Uneven Cutting

Uneven cutting is a medium severity issue frequently mentioned by internet users who own one. This zero-turn mower, with its 25.5HP Kawasaki 852cc 2-cyl gasoline engine and 11.5-gallon fuel capacity, can experience uneven cuts due to misaligned mower decks, dull blades, and inconsistent tire pressure. Online community recommendations emphasize the importance of sharpening or replacing dull mower blades and ensuring the deck is level to address this issue.

A representative from C & B Operations in Billings, Montana, a licensed John Deere service center, advises, “For the Z930M, regular deck alignment checks and blade maintenance are key to preventing uneven cutting and ensuring the mower’s longevity”​​.

Addressing these issues is not just about aesthetics—uneven cutting can stress your lawn, making it more susceptible to diseases and pests. Moreover, a misaligned deck can strain the mower’s engine, reducing its efficiency and lifespan.

How to Fix Uneven Cutting:

  1. Check the mower deck alignment—ensure it’s level and has the correct rake adjustment.
  2. Inspect the blades—if they’re dull or damaged, sharpen or replace them.
  3. Regularly check tire pressure—ensure all tires have consistent and recommended pressure.
  4. For optimal performance, maintain the mower’s mechanical components, like the electro-magnetic clutch and the hydrostatic transmission.

If you don’t already own a John Deere Z9XX, should you buy it?

Naw, I don’t think so. The X300 is better. Users have reported issues, such as engine stalling, hydraulic leaks, and uneven cutting. While the John Deere Z930M is not the X300, it’s worth noting that John Deere products can have their quirks. Users from TractorByNet and GreenTractorTalk have mixed feelings—some praise its performance, while others highlight mechanical problems. If you’re seeking reliability, you might want to consider alternatives like the Husqvarna YTH18542. Remember—every mower has its pros and cons, but it’s essential to weigh them against your specific needs and the experiences of other users.

Why trust Igra World?

At Igra World, we meticulously researched—identifying its glaring flaws. Our seasoned mechanics collaborated, diagnosing specific issues like engine failure and faulty wiring. We tested—rigorously—addressing each problem, documenting our findings. Evaluating this model, we found it lacking. Analyzing its performance, we resolved: it’s not up to par for discerning buyers. Trust us—we’ve seen better.

About Jeff Henderson

Have a question regarding your lawn tractor? Igra World writer Jeff Henderson may have covered it already on this site, if not you can contact him at jeff.h@igra-world.com and (417) 414-5099 if you have an problem you can't find an answer to. Jeff is a part time tractor mechanic and landscaping company owner who lives in Springfield, Missouri. He has over 10 years of experience in tractor repair and small engine repair, and has worked with John Deere, Husqvarna, Toro, Troy Bilt, Cub Cadet and Kubota equipment.

Join the discussion