Lawn mower gas caps can become stuck from time to time. When this happens, it’s important not to damage the gas cap or tank when attempting to remove it. Let’s go over some ways to remove a stuck gas cap on your lawn mower and some tips to prevent it from happening again.
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How to Get a Stuck Gas Cap Off a Lawn Mower
There are three main types of lawn mower gas caps: plastic threaded, metal-winged, and ratchet safety. Each gas cap is made of different materials and has different designs to attach to the gas tank. Let’s go over the different gas cap designs and how to remove them when stuck.
What You’ll Need to Remove a Stuck Gas Cap
Removing a Plastic Threaded Gas Cap
Place a shop rag over the cap to protect the plastic and make the cap easier to grip. Grip the cap and rag with a large pair of Channelocks. Keep the tool centered as you slowly begin to turn it. If you go off-center, there is a higher chance the plastic will crack. Stop if there is too much resistance and the tank neck starts to bend. Readjust the Channellock and try again until the gas cap starts to come loose. Patience is key!
Removing a Metal Winged Gas Cap
You probably won’t come across a metal-winged gas cap unless you have an older model. If your metal-winged gas cap is stuck, you can follow the same method and use the same tools for removing a plastic gas cap. The only difference is that a metal-winged gas cap only needs to be turned halfway.
Removing a Ratchet Safety Gas Cap
You probably have a ratchet safety gas cap if you have a larger lawn mower, like a ride-on or zero-turn. These gas caps click and turn without tightening, much like the ones used on cars. Ratchet safety gas caps are similar to safety caps on medicine bottles. So, all you need to do is push downwards while loosening it.
Tips to Prevent a Lawn Mower Gas Cap From Getting Stuck
Dealing with a stuck gas cap is no fun. So, let’s look at ways to prevent it from getting jammed again.
Preventing a Plastic Threaded Gas Cap from Getting Stuck
The easiest way to prevent a plastic threaded gas cap from getting stuck is by making sure you put it on correctly in the first place. The cap should go on effortlessly with little tightening. Stop if you feel any resistance. The last thing you want to do is cross-thread the cap. Also, overtightening the cap can damage the threads on the cap and tank. Overtightening can happen if the rubber washer that forms a seal between the cap and tank is worn-out or missing. Check for the washer and replace it if needed.
Preventing a Metal-Winged Gas Cap from Getting Stuck
If you have a metal-winged gas cap on your lawn mower, then it likely means you have an older mower. So, the first thing you want to do is inspect the gas cap for any damage. It is normal for an older gas cap to become bent or worn out. Next, you can try to straighten the cap and test if it fits properly. It should go on smoothly. If you’re noticing resistance, then it is likely misshapen and will get stuck.
The second thing you want to check for is an internal washer. Like on the plastic caps, the washer will prevent you from overtightening the cap. Inspect the washer and make sure it is not damaged. You’ll have to replace it if it’s too worn out or missing altogether.
Lastly, inspect the metal gas cap for corrosion. With time, metal-winged gas caps develop rust. This rust can cause the cap to become stuck on your lawn mower. So, spraying it with WD-40 should help get the cap on and off smoothly.
Preventing a Ratchet Safety Gas Cap from Getting Stuck
Even though ratchet safety caps are pretty tough, they can still get jammed. The best way to prevent this type of gas cap from getting stuck is to make sure you don’t overtighten it. Stop tightening it after you hear it click once or twice. The clicks signify the gas cap is secure on the tank. Ratchet safety gas caps also have rubber washers that create a seal. Check the washer and make sure that it doesn’t need replacing.
Other Reasons Why Gas Caps Get Stuck
Human error is not the only cause of stuck lawn mower gas caps. Conditions within the lawn mower can cause problems with the gas cap. One common situation is when excess heat causes the plastic in the gas cap and tank to expand. This is especially common when mowing in very hot weather. When this happens, turn the mower off and park it in a shaded area. After it has cooled down, the plastics will contract, and you should be able to remove the gas cap.
Excess pressure is another common reason gas caps get stuck. This can happen when the fuel boils or the gas cap doesn’t vent properly. Problems like these create additional pressure or vacuum, making it hard to loosen the cap. Again, let the lawn mower rest. After a while, the pressure will decrease, and you’ll be able to loosen the gas cap.
