It is common for a carburetor to become dirty from the fuel you run through your mower. Ethanol and other fuel additives can develop a gummy substance that can clog components in your John Deere mower carburetor.
If you are a little mechanical and don’t mind working with small components, you should be able to tackle cleaning your carburetor. If not, have your local lawn mower repair shop clean it for you.
Symptoms of a Bad Carburetor
When your carburetor is acting up, you will notice these symptoms due to your mower running with the incorrect fuel-to-air mixture or having a blockage:
- Mower won’t start
- Mower starts and then dies
- Backfires from running lean
- Engine is sputtering and running rough
- Engine is surging
- Engine is consuming too much fuel
This post may include affiliate links. Purchases made through these links may provide a commission for us, at no extra cost to you. As an Amazon Associate, we earn from qualifying purchases.
Follow all safety instructions provided in your equipment operator’s manual before diagnosing, repairing, or operating. Consult a professional if you don’t have the skills, or knowledge or are not in the condition to perform the repair safely.
11 Steps to Clean Your John Deere Lawn Mower Carburetor
Spray Carburetor Cleaner in the Air Intake
First, identify if you need to take your carburetor apart for cleaning. Do this by removing your air filter from the air filter housing.
Spray carburetor cleaner into the air intake and start your engine. If your mower starts and then shuts down, you must take apart your carburetor and clean it.
Gather Tools and Items
- Socket/ratchet set
- Carburetor cleaner
- Thick wire
- Needle nose pliers
Take Photos for Reassembly
There are many small parts you are disassembling when cleaning the carburetor on your John Deere mower. These days, most people have a cellphone with a camera on them.
Use the camera to take photos of your carburetor to document the steps you performed to take apart your carburetor.
These pictures will be helpful when you reassemble your carburetor to make sure all the parts get installed in the right places. You don’t want to be left with any extra pieces or get the installation wrong.
Shut off Your Fuel Supply
Use your fuel shut-off valve to stop fuel flow. Remove the fuel line from the carburetor.
Remove Your Throttle Cable & Choke Cable
If your John Deere has a throttle and choke cable, remove it.
Detach the Filter Housing
Remove the hardware that attaches the carburetor to the air filter housing.
Remove the Springs
Next, you need to slowly remove the springs. Be careful to not stretch out the springs. You may have to twist the carburetor a bit to get the springs to come off.
There is a gasket located between the engine block and the carburetor that you need to not tear. If you do, you’ll have to purchase a new gasket.
Remove the Carburetor Bowl
The carburetor bowl stores a little gasoline inside your carburetor. You’ll find the bowl at the bottom of your carburetor held on by a screw.
Clean around the outside of your carburetor bowl before removing the screw from the bottom of the bowl. Have a rag available to catch any remaining gas in the bowl.
When you remove the bowl, be careful not to damage the o-ring that sits between the bowl and the carburetor. This o-ring looks like a rubber band.
Take care not to get carburetor cleaner or any other substance on the o-ring. You won’t be able to reuse the gasket if it stretches because of this substance.
Check the Stem for Clogged Holes
There is a little piece that hangs down from the center of your John Deere’s carburetor. This is known as the stem. There are holes in the stem that can become clogged from running old fuel.
When this happens, the stem will not draw fuel up to the jet. Use a flashlight to better see the holes in the stem. Clean the holes with a thick wire to unplug the holes.
Check the Carburetor for White Crusty Buildup
Check out the carburetor and its parts for a white crusty buildup which is the result of fuel additives including ethanol. Try to remove as much of this crusty material as possible using carburetor cleaner. It is almost impossible to remove all the crusty deposits.
Reassemble Your Carburetor
Once you have cleaned your carburetor and ensured the float and float needle are moving freely, it’s time to reassemble it. Reference the photos you took earlier when putting your carburetor together to make sure all the small parts get put back in the right places.
Reattach components to your carburetor including the springs, filter housing, throttle, and choke cables (if the mower uses them), and the fuel line.
Fill Your Fuel Tank with Fresh fuel with a Fuel Additive
Start your fuel flow. Use fresh fuel mixed with a fuel additive, like Sea Foam Motor Treatment, in your John Deere’s fuel tank. Give the fuel a chance to fill the bowl of your carburetor and start your engine.
The fuel additive stabilizes your fuel and cleans your fuel system. Read more about the advantages of Sea Foam here.
Replace or Rebuild Your Carburetor
If cleaning does not work because your John Deere carburetor is corroded or has damaged parts, it may be your best choice to replace the carburetor.
To make sure you get the correct carburetor, have your engine model and spec number available when ordering your new carburetor from your local engine dealer or online.
A carburetor rebuild kit to repair your carburetor may be available from your local John Deere dealership if you choose to rebuild your carburetor instead of replacing it.
Check the cost of the rebuild kit in comparison to a new carburetor. You may be surprised to find there may not be a significant price difference.
John Deere Problems Could Be More than a Carburetor Problem
A dirty or bad carburetor can be a cause of your John Deere mower not starting, quitting after starting, and leaking fuel. There are many other items that can cause these problems. To find out more about these causes and how to solve them, check out the links below.