The 100 series lawn mowers from John Deere are some of the best bang-for-the-buck machines out there. With an oil capacity of 1.4 liters, it has more than enough gas in the tank to mow a flat lawn.
Sure, it does lack performance when it has to pull too much load, but that’s the tradeoff with any affordable mower. And while it is great and all, the transmission system of the John Deere 100 series mowers leaves a lot to be desired.
There are many incidents of the transmissions failing or acting up, which can lead you to think that the 100 series is not a decent mower. But the truth is, all of these issues can be fixed if you know what you are doing.
And at this price point, it’s natural for the mower to have some issues. In this article, I will give you a quick rundown of the common transmission problems in the John Deere 100 series lawnmowers and help you find the possible fixes.
By the time you are done reading through this post, you should be equipped to handle these issues by yourself.
Why Does the John Deere 100 Series have Transmission Problems?
The transmission system in the 100 series mowers by John Deere features a hydrostatic design. It is significantly different from the regular transmission system and is also pretty critical.
With this transmission system, the power transferred to the pump comes directly from the engine via pressurized liquid. This is actually the reason why the 100 series mowers are such a workhorse.
But this design also opens it up to a host of problems. For instance, if air gets into the system, the whole transmission mechanism will start acting up. The design makes certain parts of the machine vulnerable to mechanical issues.
This is the reason why the transmission system in these mowers faces frequent issues. So, while the hydrostatic transmission system allows the machine to outperform other mowers in a similar price range.
It also makes it susceptible to more mechanical faults. That is why the John Deere 100 series mowers require a bit of extra maintenance to keep the mechanical problems at bay.
Common Transmission Problems in the John Deere 100 Series and How to Fix Them
The thing about transmission systems is that issues in them manifest in different ways in your vehicle. And the first step to fixing the problems is to identify the symptoms.
So here are a couple of issues that may come up in your John Deere 100 series lawnmowers because of the transmission system. I’ll also discuss the troubleshooting steps to make things as easy as possible for you.
1. Gear Not Engaging From The Neutral Position
If you see that the driving gear in your lawn mower does not engage and is stuck in the neutral position, there is a very high possibility that the transmission system is the culprit.
As weird as it may sound, this is actually a very common issue in most affordable mowers in the market. When you turn off your lawnmower, putting the gear back in its neutral position, it will get stuck. So, when you turn the vehicle back on, you won’t be able to change the gear.
Thankfully, solving this issue is pretty simple. If you notice this problem, immediately shut down the engines. You need to then move the output shaft around to unjam it. With some elbow grease and luck, the output shaft should unclog, and you should be able to engage the gear.
2. Engine Suddenly Stops
Imagine this – you are mowing your front lawn one early mowing. The vehicle is running smoothly, and everything seems perfect. But suddenly, the lawnmower shut down without any warning. If this seems familiar, then your mower probably has an issue with the transmission system.
With hydrostatic transmission systems, there is a safety feature that shuts down the vehicle instantly if there is any malfunction. And since John Deere 100 series lawnmowers come with this type of transmission, any fault in the system causes the engine to shut down.
To fix this, you will need to check the transmission drive belt. But before you get started, make sure you are wearing your safety gloves and that the engine has had time to cool down. You want to look for any debris, stone, or sticks that may have gotten stuck on the belt. Once you remove the clog, it should start working again.
3. Drivability Issues
Issues in the transmission system will naturally cause some issues in the drivability. If you suddenly see that your John Deere 100 series mower is shifting from one speed to another on its own, then you probably have an issue with your hydrostatic transmission system.
The issue mainly occurs if air gets into the hydraulic system. Typically, the air filter is designed to keep outside air out of the transmission. But a faulty pump or air filter can easily let it in. If that happens, then your vehicle will start showing weird issues when you operate it.
To fix this issue, you need to rebuild your hydrostatic transmission system. I would recommend taking your vehicle to a professional workshop for this, though, as it might be a bit too much to handle for a casual homeowner.
If you want to do it by yourself, you need to first remove the whole transmission system from the vehicle. Make sure you have all the parts of the transmission system in front of you. The major components are – the drive pulley, the input pulley, the vent cap, the filler cap, and the drain cap.
Inspect each component and look for any signs of damage. Replace the parts that need replacing and then assemble them all together. Finally, put the transmission system back in place and test out your vehicle. Of course, if too many components are damaged, replacing the entire system is the better approach.
4. The Wheels Not Spinning
Another issue that may come up in your vehicle is that when you start the engine, the pulley spins, but the wheels do not move. This is a telltale sign that the transmission system in your mower is damaged and needs fixing.
If you are lucky, the main reason why this is happening is that air got into the transmission pump. In that case, you need to purge the transmission system. It’s a bit of a long procedure, so take your time and try to follow my instructions to the tee.
- Position your mower on level ground and engage the parking brake.
- Lift up the rear wheels using jackstands.
- Check the oil reservoir and see that it is filled properly.
- Disengage the transmission system following the instruction manual.
- Get on the operator’s seat and fire up the engine.
- Now, move to the slow position on the throttle control and position the control levels to the neutral position. Disengage the brake pedal
- Next, push the control lever forward and hold it at that position for five seconds.
- Then reverse the control lever and hold that position for five more seconds.
- Repeat the forward and reverse motion about six to seven times
- Then put the control lever back in neutral, turn off the engine and engage the parking brake
- Reinstall the transmission and remove the jackstand.
- Turn the engine on and move the control lever forward, and your vehicle should start moving.
- Move about five feet forward and reverse the control lever to move back the same distance.
- Repeat the two steps about three times
With this done, the air is purged from the system, and your transmission system should work as intended.
How to Prevent Transmission Problems in the John Deere 100 Series Lawnmower?
While the transmission system is not exactly the strongest part of the 100 series mowers by John Deere, there are ways to make sure you don’t have to deal with any issues here. The most important advice I can give you is to take regular care of your vehicle.
Affordable lawnmowers are rarely as durable or as well made as the high-end, expensive models. And it makes sense since the manufacturers need to cut corners to cut down on the cost.
However, if you check the engine and the transmission of your mower once every month and take it to a workshop every two months, there is very little risk of any damage to your lawnmower. And even if there is a chance of any transmission issues, you will be able to catch it before it becomes too much to handle.
The John Deere 100 series lawnmowers offer amazing performance for the price. But like any other affordable mowers, they have their fair share of issues. However, if you regularly maintain your mower, you should not notice any of these issues frequently in your vehicle.
Hopefully, my complete guideline on the John Deere 100 series transmission problems could help you identify and fix any issues you may be having in your lawnmower. Good luck!