How to Repair a Plastic Gas Tank

Car repairs can be expensive because you will be paying for parts and the professional who will have to work on it. However, in many cases, there are ways to do some small fixes that will still get your car back to normal for a fraction of the price of having it replaced or repaired.

One of these cases is a leak in your gas tank. Many cars have fuel tanks made of plastic because they are very convenient. Although metal ones may last longer, they will cost more to maintain. They are more likely to rust, corrode, leak, or break after a long time. In comparison, plastic costs less, is lighter and more durable because they are not at risk of corrosion and rust. Lastly, they are quite easy to assemble.

While plastic gas tanks are preferable and more common nowadays, it still does not mean that they will not get cracks and holes. Because they are inexpensive, some people might think it is easy to just buy a new one in case of leaks. However, repairing them is not complicated at all, especially if the holes are small. This means you can put off the replacement for another time.

There are 3 different methods commonly used to repair plastic fuel tanks.

First Method: Use Epoxy Glue

What You Need:

• Shop Cloth
• Alcohol
• Sanding Paper
• 2 Part Epoxy Glue
• Fiberglass Patch

1. The first step is to drain the tank of all the fuel inside and leave it to dry completely. When it is ready, you should sand the parts of the tank that has a crack or hole. Lastly, clean the area you will repair with some cloth that has been saturated with rubbing alcohol.
2. Next, mix together 2 part epoxy before applying it around the edges of the hole or crack. Cut your fiberglass patch so that it is big enough to cover the leak plus some extra so that it overlaps the opening.
3. Place the patch over the hole and press it down on the epoxy you applied. Add more epoxy to the surrounding area and the patch before pressing it down until the patch is saturated.
4. Leave it to dry before sanding the entire area. You can spray paint the patched area if you want to.

Second Method: Seal With A Plastic Welder

What You Need:

• Plastic Welder – make sure you specify the use so that you will have the exact rods you need
• Protection like Eye Gear, Welding Gloves and Helmet
• Plastic Welding Rod
• Sandpaper

1. The first step is to find the right plastic welder. Buying one is not necessary, as there are ones out there that you can rent. However, it is important that you get the right one, so ask a salesperson or an expert for advice, as you need to be sure that the rods are correct.
2. Remove the fuel tank from your car and bring it to a secure area where you can do the welding. Before working, you need to drain all the contents of the tank and leave it to dry fully outside and inside. Before welding, put on all your welding protection.
3. Using the plastic welding rod that has been recommended for this task, fill the leak or the hole. Begin in one edge and make one round around the hole. Start crossing over the hole so that the rod fills it in completely.
4. Wait until it sets before sanding it so that the surface smoothens out. If needed or desired, paint it over with spray paint. Lastly, put the fuel tank back to your car.

Third Method: Use A Soldering Gun

What You Need:

• Soldering Gun
• Sandpaper
• Plastic Patch
• 2 Part Epoxy Glue

1. First, drain the fuel tank completely and clean it with some soap and water. Make sure that it is cleaned completely both inside and out. Use the sandpaper to smoothen the edges of the hole to be repaired.
2. Get a plastic patch that has a material similar to the one of your gas tank and cut it so that it is slightly bigger than the leak or crack you are repairing.
3. Warm up the electric soldering gun before dragging it around the hole’s edges to make a trench. Move the gun from one side to another so that the plastic gets pushed back into the trench. Take the plastic patch while the fuel tank is still soft from being soldered. Lay it on top of the crack and continue to solder the whole area so that the plastic smoothens out and fuses them together.
4. Wait until it is completely cool and dry. Mix the epoxy glue before covering the whole area that has been patched. Once it is set up, sand the area and spray it with plastic paint if you want to.

Tips On Repairing Plastic Fuel Tanks

One of the most common questions from car owners is “which is the most effective?“ In terms of ease, the epoxy glue is the least complicated and does not require any tools. However, the downside is that the patch only stays good for a short period of time.

If you want to try out the other methods, make sure you practice first before working on your actual fuel tank. If you rented out the plastic welder, for example, you can ask the rental shop to demonstrate how to use it.

Safety Precautions While Repairing A Gas Tank

Because you are working on a part of the car where fuel is stored, you need to take the necessary steps to stay safe while doing your DIY repairs.

First of all, make sure that the tank is fully drained of all the fuel before working on it. You should never take steps that can create a small spark, as it may lead to a fire. A plastic welder is safe to be used around gas and fumes, but never use it where there is an open flame.

In cases of small holes or leaks in your plastic fuel tank, you might want to explore taking one of these easy steps to fix it before considering a full replacement. Not only does it save you time and effort from bringing your car to the mechanic but you will also save money on the process.

Sources:

1. Metal Glues and Fillers – HowStuffWorks
2. How to Repair the Plastic Gas Tank on a Stihl Weed Eater – Hunker