How to Fix Plastic Gas Tank on Lawn Mower?

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The plastic tank on a lawnmower is a sufficiently sturdy and reliable piece. It can handle years of use and work for much more time than you expect. But even then, it can still crack, split or break. 

That’s why it is essential to know how to fix a lawn mower gas tank. When the time comes for the gas tank to be repaired, you’ll know how to tackle the issue. 

Because the plastic tank of a mower is usually made of polyethylene, it is not the hardest thing to fix. And with a proper repair, you may end up fixing it permanently.

Want to know how it’s done? Then take a look below. 

Step-by-Step Guide: How to Fix a Plastic Gas Tank on Lawn Mower

The process of repairing a plastic gas tank can be somewhat confusing at first. But if you follow our advice and every step in this guide to the letter, then it shouldn’t be much of a problem.

Below, you’ll find everything there’s to know about fixing the plastic tank from your lawnmower

Things to Consider

While the process of fixing the gas tank may feel like a huge endeavor, it’s not. You just need to be prepared for it. That’s why you should consider these tips:

  • The repair process may take anywhere from 10 minutes to 1 hour or a little more. 
  • Time is of the essence when it comes to fixing the tank. As you’ll be using epoxy, you’ll need to act rapidly to prevent the plastic from drying up mid-operation.
  • You’ll be using epoxy to repair the tank. This adhesive may melt into the plastic as you’re working with it. Don’t worry when this happens, it’s typical.
  • This fix should be permanent unless you make a mistake. So be careful and pay attention to the job at hand. 

Did you internalize these things? Then you’re ready to start fixing the tank. 

Items You’ll Need

  • Phillips Screwdriver
  • Utility Knife 
  • Sandpaper
  • Metal Spatula
  • Plastic adhesive (Epoxy)
  • Plastic or Fiberglass Patch
  • Work gloves 
  • Brush (Optional)
  • Rag (Optional)

As you can see, you don’t need many tools. But you will still need to spend a few bucks on the epoxy and the fiberglass patch if you don’t have any. 

Once you’ve gathered these items, then you can proceed to repair the tank. Follow these steps: 

1. Remove the Tank

lawn mower gas tank

Start by getting the tank off the mower. This will help you prevent any damage to the mower and allow you to work comfortably. 

  • Put on your work gloves before doing anything else. Then proceed to place the mower in a flat area where you can work comfortably. 
  • If there’s a hole in the tank, be careful not to spill too much gas around. You may need to drain all the gas beforehand. 
  • Now look for the screws and hooks that connect the tank to the mower. Proceed to set them all off so you can remove the plastic piece.
  • Get the fuel hose clamps out, the hooks that keep it attached to the engine, and the screws. Then it should be ready to take off the mower.

After removing the tank, you will need to prepare it for a safe and comfortable fix.  

2. Clean the Tank

lawn mower gas tank

 

Because you’ll be using heat on a plastic piece that contains gas, you’ll want it to be as safe as possible. For that, prepare it following these tips:

  • If you drained the tank already, there’s no need to do it again. But still, you should check for any residual gas inside and get it out.
  • Because you’ll be applying epoxy, you want it to be as clean as possible. So you need to get rid of grease, wax, dirt, debris, and any other contaminant inside the plastic tank. You can use water for this. Get rid of anything inside the tank. 
  • Apart from the interior of the tank, we strongly recommend cleaning the exterior as well. Do this by dampening a rag and rubbing it all around. Also, you can use a brush with some soap as well.
  • Let the tank dry off for a few minutes. Accelerate the process by wiping it off with a dry towel.

After preparing the tank, you’re ready to start the fixing process. 

3. Prepare the Area to Fix

You should proceed to cut any rough spot or plastic excess on the affected area. Then, you’ll need to sand it. 

  • Use the utility knife to cut any plastic excess. You can heat up the knife with a heat gun to make the cutting easier.
  • Once you’ve cut out any plastic excess, you can sand the whole area. Use the sandpaper for this. This should take a couple of minutes. 
  • The focus is to leave a rough area so the adhesive sticks to the plastic more quickly. Also, plastic strips that stay hanging may affect the effectiveness of the repair – so you must cut them down.

By now, the area should be ready to start the fixing process. 

4. Cut the Fiberglass/Plastic Patch

With the area to fix clean and roughed up, it is now time to measure and prepare the patch you’re going to use to repair the tank. Follow these tips:

  • Grab the fiberglass or plastic patch and compare it to the area you want to fix. The patch should be at least one and a half times larger.
  • If the patch is too large for the area, then cut it down in a way that it overlaps the whole affected area. 
  • Take your time trimming the patch. Be sure it is a perfect size and shape. Also, be sure it is larger than the affected area, or it won’t work.

Now that you have the patch ready, it is time to start 

5. Prepare the Adhesive

lawn mower gas tank

For the patch to fix the plastic, you need to apply an adhesive. But first, you need to prepare it:

  • Remember to follow the instructions of the epoxy before starting. This way, you’ll avoid making a mistake. Remember, you’re fixing a gas tank, so you’ll want to do it properly. 
  • Most plastic epoxies come with a two-part mix. You will have to blend these two parts together to create the adhesive substance. Use the added mixer/stick for this. 

Once the adhesive is ready, you should hurry up to apply it. 

6. Apply the Adhesive & Patch

For the plastic/fiberglass patch to stick to the plastic, it is vital to apply the adhesive first. Here’s how:

  • Cover the entire affected area with the adhesive. Remember to use the metal spatula for this, plastic spatulas may melt in the process.
  • It is vital to cover not only the damaged area but also its surroundings. But don’t use the whole adhesive mix, leave some for the exterior.
  • After applying the adhesive, you can proceed to place the patch on the affected area. Use your hands for this, but try not to get the adhesive on your hands. 
  • Press the patch firmly into the affected area with the adhesive. Be sure it fits tightly, so it doesn’t come off afterward. 
  • Finish by covering the whole patch and the rest of the affected area with the remaining adhesive. It should cover the borders of the patch, at least.

Now you’ve successfully applied the patch on the plastic tank. It is time to let it dry up.

7. Let It Cool & Inspect 

After applying the patch and the adhesive, the affected area should be covered. You will need to let the tank cool down for a few hours.

  • You will have to leave the tank to rest for at least 3 hours while it dries up. While waiting, search for any area on the patch that looks too thin or weak.
  •  If necessary, you may need to apply a little more adhesive. The epoxy will add an extra layer of protection to the whole area. 
  • Once the adhesive cools down, check once last time in search of any weak or thin area. If there’s none, then the tank is fixed.

Still, we recommend testing it before calling it done. 

8. Test the Tank

lawn mower gas tank

After letting the tank sit for a while with the adhesive and patch fix – then you should test it out. Here’s how:

  • No need to place the tank on the mower to test it. You can proceed by filling it up with water entirely and see whether it leaks.
  • Remember to close the openings on the bottom and/or sides while filling it. Check that there are no leaks. 
  • If the tank fills completely and there’s no leak to worry about (especially from the repaired area), then you’ve successfully fixed your lawnmower plastic tank. 

You can now proceed to mount it on your mower, fill it up with gas, and start the mower to see how it works. 

This fix should be permanent, so you’re ready to enjoy the mower for a long time with a repaired tank. 

Fix the Plastic Gas Tank on Lawn Mower Now!

Now that you’ve reached this far into this guide, then you should be ready to fix any broken, cracked, or split lawn mower gas tank.

If you follow each step and recommendation to the letter, then you should do it seamlessly and quickly. So don’t hesitate and start fixing that gas tank now. Your lawn is waiting!

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