John Deere Z930M Problems & Fixes [Solutions Explained]

The John Deere Z930M is an agile zero-turn mower that makes mowing large lawns with lots of features super easy.

However, like with any piece of machinery, there are bound to be problems that you eventually run into. Luckily, we are here to help you troubleshoot and fix these issues at home.

You could encounter many issues, but the most common John Deere Z930M problems include a sputtering engine, leaky transmission, and mower blades stopping.

Transporting and repairing a zero-turn mower like this can be costly and full of hassle, so getting to know your machine and how to fix it yourself is a must.

This article will outline the seven main problems with the John Deere Z930M and give you some quick and easy fixes for each one.

Gardenaholic Tip: Zero-turn mowers are useful but can be very dangerous on hills. Check out our deep dive on how to operate them safely on hills.

7 Common John Deere Z930M Problems and Fixes

You may run into many issues with your John Deere Z930M, but luckily, they are mainly issues that you should be able to fix yourself at home.

You may need a small toolkit to execute some of these fixes, but every household can benefit from a small set of tools.

Sometimes, you may need to replace some parts, and we recommend sourcing these parts from John Deere to ensure the quality.

Here are the seven most common issues with the John Deere Z930M:

Engine Sputtering

This is the issue you are most likely to notice with this model, and it happens for several reasons.

The PTO could be faulty, and the belts may be damaged. It also could be poor quality or old fuel as well as a blocked air filter system. Lastly, it could be a faulty fuel pump.

The Fix: In the case of the PTO, we recommend checking its functionality using a multimeter and inspecting the cables for damage. Replace any worn or old parts.

Secondly, if your gas has been in the mower for a while, you need to replace it with fresh, high-quality gas. While in that area, check the fuel pump functionality and replace it if needed.

If neither of these fixes works, check the air filter system and clean it out.

Bad Fuse

If you are having trouble starting your engine but have already tried jumping the battery, it’s likely that you have blown a fuse.

The Fix: Try placing the fuse holders in line instead of bypassing the fuse blocks to remedy this. If worst comes you worst, you will need to replace it with a new 20 amp fuse.

Blocked Fuel Filter

The symptoms of a blocked fuel filter are overheating, sputtering, issues starting, and irregular stalling.

If you are experiencing any of these issues, check the fuel filter to see if it has been clogged or saturated with water.

The Fix: The only way to fix this issue is to buy a fuel filter. We suggest buying one directly from a John Deere distributor to ensure the best quality.

Bad Electrical Coil

Before you can ascertain that your issue is the coil, you must rule out whether it is a spark plug issue.

Do this by checking that all spark plugs are in place and clean.

If the spark plug is only firing from one side, unplug it and ground it against the engine. Attempt to start the engine and check for firing. If it doesn’t fire, remove the wire from the primary coil and test the firing again. If this works, then you know it is a coil issue.

The Fix: The only option is to replace the old coil with a new one from John Deere.

Mower Blades Stopping

The blades stopping out of nowhere can be a result of the PTO clutch disengaging or a belt issue, but the most likely cause is an issue with a safety switch.

The safety switch in the John Deere Z930M is situated under the seat of the mower so that it is activated when someone sits in the seat. If this is faulty, the blades may disengage incorrectly.

The Fix: Unfortunately, the only way to fix this is to replace the safety switch. If you know what you’re doing, this is a DIY job.

Transaxle Issues

If your transmission is making a lot of noise during operation, the transmission fluid may be contaminated.

The Fix: Luckily, it is easy to replace the transmission fluid yourself at home.

To prepare, turn the engine off, remove the transmission key and disengage the blades. Unplug and remove the battery before opening the cap and draining the transmission fluid into a container.

Refill with new transmission fluid and replace the battery.

Leaking Transmission

Unfortunately, a leaking transaxle transmission is very common with this model of lawnmower, the John Deere Z445 suffers similar problems, especially around the seals.

The Fix: This is the only issue that we are highlighting today that has to be handled by a professional. Luckily, since it is a common issue, it is covered under your warranty.

Gardenaholic Fact: Zero-turn mowers allow you to mow in small, awkward spaces because the machine can execute a 180-degree turn on its axis.

Frequently Asked Questions:

What engine does the John Deere Z930M have?

 This zero-turn mower has an air-cooled, vertical shaft, 25.5-hp (19.0-kW) gas engine, which is injected electronically. It runs on regular, high-quality gasoline.

What size deck does a John Deere Z930M have?

The deep-deck design is 54 or 60 inches depending on the model.

What kind of oil does the John Deere Z930M take?

All John Deere mowers use 10W30 oil if they have gas engines, which the Z930M is. The engine needs around two quarts for each change.


The John Deere Z930M is a very hardy and useful mower from a brand that promises long-lasting quality.

We have clearly outlined the seven main issues with the John Deere Z930M, which, to sum up, are the sputtering engine, starting issues, blocked fuel filter, bad electrical coil, mower blades stopping, transaxle issues, and leaking transmission.

With these helpful tips and tricks, you should be able to keep your zero-turn mower running at home without having to spend any money on repairs.