😋😒😠 This article was co-authored by wikiHow staff writer, Eric McClure. Eric McClure is an editing fellow at wikiHow where he has been editing, researching, and creating content since 2019. A former educator and poet, his work has appeared in Carcinogenic Poetry, Shot Glass Journal, Prairie Margins, and The Rusty Nail. His digital chapbook, The Internet, was also published in TL;DR Magazine. He was the winner of the Paul Carroll award for outstanding achievement in creative writing in 2014, and he was a featured reader at the Poetry Foundation’s Open Door Reading Series in 2015. Eric holds a BA in English from the University of Illinois at Chicago, and an MEd in secondary education from DePaul University.
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😋😒😠 Plastic gas tanks are in high demand in the world of motorcycle racing and ATV enthusiasts. A plastic gas tank can weigh less than half of a comparable metal gas tank and it is easy to mold into shapes to fit odd configurations. Seamless gas tanks seldom leak and are impervious to the rust and corrosion that affect metal tanks. If a plastic fuel tank does sustain small holes or tears, there are several fairly easy ways to make the repair.
Method 1Method 1 of 3:Seal Plastic Gas Tank with Epoxy Glue
- 1Drain the gasoline from the tank and allow it to dry. Sand the area around the hole or crack, and clean the area with a shop cloth saturated with rubbing alcohol.XResearch source
- 2Mix the 2 part epoxy together and apply all around the perimeter of the opening.XResearch source Cut a fiberglass patch large enough to cover the opening and overlap it.Advertisement
- 3Place the fiberglass patch over the hole and press into the epoxy. Apply more epoxy to the patch and surrounding area, pressing firmly to saturate the patch.
- 4Allow to dry, sand the patched area smooth and spray paint with a plastic paint if desired.
Method 2Method 2 of 3:Seal Plastic Gas Tank with a Plastic Welder
- 1Buy or rent a plastic welder. Tell the salesperson what you are doing with it to ensure that you get the correct rods.
- 2Remove the plastic gas tank from the vehicle, and set it up in a secure welding area. Drain the gasoline from the tank, and allow it to dry both inside and outside. Don protective eye gear, a welding helmet and welding gloves.
- 3Use a plastic welding rod made specially for this purpose, and fill in the crack or hole. Start at an edge and run the bead completely around the opening. Then begin crossing over the hole, allowing the rod to fill in the hole completely.XResearch source
- 4Allow the weld to set up, sand it smooth and, if desired, paint it with plastic spray paint.
- 5Replace the repaired plastic fuel tank on the vehicle.
Method 3Method 3 of 3:Seal Plastic Gas Tank with a Soldering Gun
- 1Drain the gas tank, and clean it inside and out with soapy water.XResearch source Lightly sand the perimeter of the area to be repaired.
- 2Cut a plastic patch, made of a similar material to the gas tank, slightly larger than the hole to be repaired.
- 3Heat up an electric soldering gun, and drag it around the edge of the crack to create a trench. Move the gun from side to side to push the plastic back into the trench. While the plastic is still soft from the soldering, lay the plastic patch over the area. Continue moving the soldering gun over the area to smooth the plastic, and fuse them together.XResearch source
- 4Allow to cool and dry completely. Mix a 2 part epoxy glue, and cover the entire area of the patch.XResearch source Allow to set up, sand and spray on a coat of plastic paint if desired.
- QuestionIs Flex Seal gasoline resistant?wikiHow Staff EditorStaff AnswerAccording to the manufacturer’s website, Flex Seal is not a good choice for sealing gasoline tanks. It’s not made to withstand a lot of heat or pressure, and it’s not recommended for use with flammable liquids, such as gasoline.
- QuestionHow do you fix a plastic gas tank on a lawnmower?wikiHow Staff EditorStaff AnswerA fiberglass repair patch will work well for this job. Drain the tank and let it dry completely first, and don’t forget to sand the area around the leak or hole so that the adhesive compound can adhere properly.
- QuestionWill Teflon tape seal in gasoline?wikiHow Staff EditorStaff AnswerNo, the gasoline will eventually break down the tape. If you want a quick and easy fix, a fiberglass patch is a better option.
- QuestionCan I use JB Weld on a gas tank?wikiHow Staff EditorStaff AnswerJ-B Weld can be used for a temporary wet repair to a gas tank. Follow the manufacturer’s instructions and be sure to treat this as a temporary fix before replacing your gas tank, as it’s only a short-term patch-up solution.
- QuestionIs J-B plastic weld gas resistant?wikiHow Staff EditorStaff AnswerAccording to the manufacturer’s website, "When fully cured, J-B Weld is completely resistant to water, gasoline, and about every other petroleum product or automotive chemical."
- QuestionWhat type of plastic is used in fuel tanks?wikiHow Staff EditorStaff AnswerThe main type of plastic used in fuel tanks is high-density polyethylene (HDPE), and this shaped by a process known as "blow molding" (Wikipedia). Other plastics that may be present in fuel tanks include: Polypropylene (PP), regrind plastic (recycled polyethylene) and possibly plastic adhesives.
- QuestionHow do you fix a leak in a gas tank?wikiHow Staff EditorStaff AnswerIt is recommended that you follow the steps above, which explain how to seal small holes and tears. If the hole or tear is large, it is likely beyond repair and will need to be replaced.
- QuestionCan a seam in a lawnmower's plastic fuel tank be repaired using a hot glue gun?Community AnswerProbably not. The best way to repair is a plastic welder with a plastic rod that matches the plastic of the tank.
- QuestionCan I seal a plastic gas tank with fiber glass?Community AnswerYes. Use a product called Tiger Paste, which is fiberglass and resin all in one. The tank MUST be clean of all dirt, grease and oil. Seal the entire tank except for filler and any vent pipes, or pick up tube openings.
- QuestionWhat grit of sandpaper should I use to sand a plastic fuel tank?Community AnswerYou should use 80 or 100 grit sandpaper. 60 grit will work, as well. The idea is to scuff the area, so that the epoxy will have a stronger bond.
- Using epoxy glue is the easiest way to seal a plastic fuel tank, but it sometimes fails after a short time.
- If using a plastic welder for the first time, practice before attempting to seal the plastic gas tank. The rental store should be able to work with you to ensure that you have no problems.
- A plastic welder is safe around gasoline and gasoline fumes, as it has a very high flash point. However, use common sense and do not use near open flames.
Things You'll Need
- Plastic patches
- 2 part epoxy glue
- Fiberglass patch
- Shop cloth
- Rubbing alcohol
- Plastic spray paint
- Plastic welder
- Welding rods
- Welding helmet
- Welding gloves
- Eye protection
- Soldering gun
About This Article
To seal a plastic gas tank with epoxy glue, start by draining the tank and letting it dry. Then, sand the area around the hole or crack with coarse grit sandpaper, and clean it with a cloth soaked in rubbing alcohol. Next, mix the epoxy glue, apply it over the opening, and press a fiberglass patch over the epoxy. Let the epoxy dry, then smooth out any bumps or unevenness with sandpaper, and spray paint with plastic paint if desired. To learn more, including how to seal a plastic gas tank with a plastic welder or soldering gun, scroll down.