How to Fix & Prevent Flat Tires on Your Mower

Tires are unfortunately known to wear down over time after extensive use. This can be a pain, but you don’t have to rush to the tire shop every time your mower tires spring a leak. With the right tools and knowledge, you can patch up your tires at home like a pro.

Keep reading to learn what you’ll need to do for this simple DIY fix.

What you’ll need:
 

 -   Tire Sealant
 -   Automotive Jack
 -   Air Compressor
 -   Air Pressure Gauge
 -   Valve Core Tool
 -   Space for driving

The Sealant

When choosing a sealant for your tire, our technicians recommend using iSeal Heavy Duty Tire Sealant. Inside this product, you can see black rubber particles that will fill any punctures or cracks that may be present on your tire. They will also act as a sealant for the rim and valve stem creating an airtight protective seal on the whole of your tire. This product is recommended for all smaller, low-speed machines such as lawnmowers, golf carts, bicycles, etc.

To treat all four tires on a tractor-style mower like the one shown here, you will need approximately three bottles of this sealant in total. Each of the rear tires will require an entire bottle, and the two front tires will each take half a bottle of the liquid.

The Fix

Before you begin to apply the sealant, you’ll first need to raise your mower using an automotive jack, properly align your tire with the valve stem at the top left or right, as shown, and finally, remove the valve core.

To remove the valve core, unscrew the valve stem camp and use the valve core removal tool to twist the core until it is loose enough to pull out by hand. This tool is included with your purchase of the sealant and will line up perfectly with the valve core when inserted inside the stem. You will also find a short, transparent tube included with the sealant.

Next, fit one end of the tube over the now completely open valve stem and the other end over the tip of the sealant bottle (Remember to cut the tip off first!), as shown. Then begin squeezing the bottle to send the sealant liquid down through the tube and into the valve stem and tire. Use the marks on the bottle label to monitor the amount of liquid being used as you squeeze. When treating front tires like the one shown here, you will want to stop once you reach the 16 oz line.

When finished, replace the valve core using the same tool you used to remove it and add air to the tire using an air compressor. You can monitor the internal pressure with an air pressure gauge as you go to ensure an appropriate PSI is reached (this is dependent on the specific tire itself). For a John Deere tractor-style mower, the front wheels usually take 14 PSI, so you’ll only need to add around 10 PSI for the test drive.

Once the tire is aired up, replace the valve stem cap and take your mower out for a drive so the sealant can coat the inside of the tire. We recommend setting a driving timer for around 10 minutes to allow the sealant plenty of time to coat the walls, treads, and beads of the tire so no cracks will be left behind anywhere like the valve stem or rim.

After 10 minutes is up, you’ll need to once again check the tire PSI to see how well it is holding air. The measurement should have remained at 10 PSI, but if not, add a bit more sealant and repeat the process outlined above until the tire is able to maintain consistent air pressure. Once it is, you can replace the valve stem cap to complete the job.

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And that’s it! You’ve now successfully patched up the tires on your John Deere tractor-style mower. If you have questions about any of the steps outlined above or are just more of a visual learner, head over and subscribe to our YouTube channel to watch our step-by-step video (also attached below)! Be sure to leave a comment with your questions to receive a personal reply from Brent himself, our resident YouTube John Deere expert.