Plastic Tank Sealer Application Directions
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FOR BEST RESULTS, PLEASE BE PATIENT DURING EACH STEP OF THE PROCEDURE. DO NOT RUSH!
Importance of Tank Preparation
To achieve expert results, please take the time to carefully read and understand the following directions before you begin your tank sealing project. Ideal Tank Sealer application temperatures are 55°–82°F (13°–28°C). Gold Standard Tank Sealer is a moisture-cured urethane therefore use only in moderate to dry atmospheric conditions. Avoid sealing tank in rainy or humid conditions. If the Sealer cures too quickly, surface bubbling will occur as a direct result of gas entrapment beneath the top surface layer of the Sealer. (NOTE: If you are sealing a Fiberglass Tank, please refer to additional instructions provided.)
All tanks, whether old or new, have oils, residues and contaminants that require thorough removal before sealing. The KBS 3-Step System is a specific process formulated to ensure superior adhesion of the coating and its long-term performance. Sealing a tank without proper prep will cause any new coating to fail. If a tank was previously sealed, you MUST remove the old coating first then proceed using the KBS 3-Step System. Please refer to additional Tank Stripping instructions provided below.
Click HERE to Get Answers To Your QuestionsStep #1 - KBS Klean — Cleaning
Drain fuel from tank. Proper fuel tank sealing also requires that the tank be removed from the vehicle. Remove any fittings such as floats, sending units and filters.
Seal all openings with high quality duct tape, pieces of rubber covering the hole secured by high quality duct tape, or cork-like stoppers secured by high quality duct tape.
Using a 1:1 dilution ratio, mix KBS Klean with hot water and pour mixture into tank. Let tank soak but always rotate it at intervals to ensure KBS Klean covers all surfaces. (NOTE: Heavy gum and varnish build-up may require extended soaking times up to 24 hours or more and/or the use of a pressure washer. Placing some nuts & bolts or loose chains inside the tank, along with frequent shaking and rotation, will help knock away loose rust and contaminants.)
Empty tank capturing KBS Klean, strain the KBS Klean solution, and repeat as often as necessary. Remember the cleaner the tank, the stronger the adhesion of the Tank Sealer.
NOTE: At this point, carefully inspect the tank with a flashlight or similar. If the tank had any loose, flaky rust, it should be removed at this point. If not, REPEAT until all loose, flaky rust is removed.
After a thorough cleaning, rinse generously with water until the solution runs clear. Drain tank and let dry.
TIP: Your tank cannot be too clean. Please spend the time required on this step.
FOR BEST RESULTS, PLEASE BE PATIENT DURING EACH STEP OF THE PROCEDURE. DO NOT RUSH!
Click HERE to Get Answers To Your QuestionsStep #2 - RustBlast — Surface Prep / Rust Removal
Pour entire amount of full strength RustBlast into a dry tank. Do not dilute. Continually roll tank around to ensure all interior surfaces are kept wet. Repeat rolling and tipping tank every 5 minutes for a minimum of 30 minutes to 1 hour. RustBlast is an acid metal etch that will neutralize existing rust and create an anchor pattern ideal for Sealer adhesion.
Important: Do not allow RustBlast to dry on surface. This avoids too heavy of a zinc phosphate buildup which can adversely affect the sealing process. After sufficient wet contact, drain & capture RustBlast in a bucket/container. Repeat process as needed. Once thoroughly etched, drain and rinse tank thoroughly several times with water. (NOTE: It is not necessary to remove every last bit of rust before sealing. Gold Standard Tank Sealer is very capable of bonding to and permanently sealing any remaining rust or corrosion.)
IMPORTANT: After rinsing, allow tank to dry completely before proceeding. Drying is best accomplished by introducing forced air into the tank by using a shop vac, blow dryer, or fan. A white powdery residue may appear after drying. This is the zinc phosphate coating advantageous for Sealer adhesion. (NOTE: Drying is a critical step. If the tank is not completely dry, the Tank Sealer will not adhere properly.)
After a good cleaning and prep and depending on the condition of the tank, any existing pinholes could become larger and/or some new holes may appear in your tank. If these holes are indeed larger than a tip of a pin, now is the time to repair them with NuMetal Epoxy Putty. (See more info below.)
Step #3 - Tank Sealer — Sealing The Tank
It is recommended to seal your tank within 10 days of cleaning and prepping it. When ready, open Tank Sealer and stir can thoroughly. Touch bottom and lift when stirring to raise and disperse any settled silver pigment. DO NOT WHIP OR SHAKE can as this will introduce air, create bubbles in the Sealer and adversely affect the sealing process.
Carefully pour entire contents of can into tank and slowly rotate and roll tank until all sides are evenly coated. Patiently work with sealer for up to 30 minutes. Please note that our Tank Sealer is formulated for use as a single thin coat application so make sure you take the time to thoroughly coat the entire tank well paying particular attention to leaky weld seams and pinholes for optimal coverage and seal.
IMPORTANT: After a thorough coating inside of tank, patiently DRAIN ALL EXCESS SEALER from tank until it no longer drips sealer. Additionally, to avoid puddling and pooling of excess sealer inside the tank, rotate the tank side to side every 5 minutes. This step is especially IMPORTANT if design of the tank makes complete draining difficult. This additional rotating of the tank will help minimize excess accumulation in any single area, and result in a slightly thicker coating on ALL walls inside the tank. Foaming and bubbling are signs of excessive Sealer accumulation and gas entrapment due to ineffective drainage. In some cases, this may cause the Sealer to not cure/adhere properly and eventually break loose. Be aware that if this situation should occur, the only recourse is to strip the tank and repeat the process.
Immediately use any left-over Sealer for exterior painting and patching to reinforce repair of pinholes and weld seams. (see further patching info below)
Immediately remove any excess Sealer from threads and fuel lines before curing. Cured Sealer cannot be removed by any solvent. When job is complete, place drained Sealer in can with lid off and let harden. Drained Sealer cannot be saved and re-used as it has been exposed to atmospheric conditions and will cure and harden in the can. (WARNING: Do not put lid on can before curing is complete as pressure may build within can and pop lid. Dispose of any hardened Sealer properly in accordance with federal, state, and local regulations.)
Allow tank to air-dry naturally in a well-ventilated area. IMPORTANT: DO NOT PLACE TANK IN DIRECT SUN OR NEAR DIRECT HEAT. Heating the tank will NOT allow sealer to cure quicker and may in fact hinder adhesion. Allow 96 hours for maximum cure. Always test the tank with water before re-filling with fuel.
Exterior Tank Patching (If Necessary)
Use KBS BackBone Reinforcing Mesh for exterior repair of pinholes or weld seams. Prior to patching, prep the outside and inside of the tank by using KBS Klean and RustBlast and allow all surfaces to dry completely. Begin by sealing the inside of the tank as outlined above. After sealing, immediately use any remaining Sealer to paint a thin layer on the exterior pinhole area(s). Using a suitably sized piece of BackBone Mesh, embed it directly into the wet Sealer and apply another thin coat of Sealer painting outward from the center. Let cure.
For exterior patching of holes that are larger than pinholes, use KBS NuMetal Epoxy Putty. Clean and prep the inside and outside of the tank using KBS Klean and RustBlast as stated above. Let dry. Scuff up area to be patched with 320 grit sandpaper then follow NuMetal application instructions. (NOTE: Allow NuMetal to cure for 12 hours before proceeding with sealing the inside of the tank.) After sealing and draining the inside of the tank, immediately use any remaining Sealer to paint a thin coating on the exterior patched area for reinforced coverage.
Clean Up
Use KBS #1 Thinner for immediate clean up. IMPORTANT: Gold Standard Tank Sealer must be cleaned up before it dries as it cannot be removed by any solvent once cured. Always wear protective gloves to avoid skin contact and temporary staining. If skin contact accidentally occurs, immediately remove with #1 Thinner or lacquer thinner followed by soap and water. If Gold Standard should stain your skin, only the course of time will remove it.
Stripping Old Coating (If Necessary)
Use KBS Strip for the most effective removal of an old failed coating.
KBS Strip is designed to work effectively when the ambient AND tank surface temperatures are between 60–85°F. However, KBS Strip is MOST EFFECTIVE when the ambient and surface temperatures are above 70°F. Said in Another Way: The Warmer, The Better!
Pour some KBS Strip into tank and carefully rotate tank to allow contact with all sides. It may take multiple applications of KBS Strip to finish the job completely. If an area needs extra attention, prop the tank so that the excess collects on that area. Continue until the majority of the remaining sealer is loosened and/or removed. Old Sealer may come loose in big chunks or small pieces so use a long tweezers-type tool to help remove it from the tank.
After KBS Strip has been allowed to work, pour out KBS Strip, capture, and strain into an appropriate metal container for possible reuse. Reuse the KBS Strip as many times as needed to remove the old liner in the tank.
Rinse tank thoroughly with water. If any part of the sealer still remains, repeat Tank Stripping steps until old sealant is removed.
After stripping is complete, rinse tank generously with water and proceed with the KBS 3-Step System for Tank Preparation and Sealing. (NOTE: When stripping a Fiberglass Tank, surface contact with the stripping agent should be kept to a minimum to avoid the attack and weakening of the fiberglass resin.)
NOTE: Extra care needs to be taken when using KBS Strip to avoid contact with exterior paint of a tank. KBS Strip is a powerful paint remover and WILL INDEED remove exterior paint on gas tanks.
Fiberglass Tanks
The procedure for sealing a Fiberglass Tank is the same except for a variance in Step #2 - RustBlast. For this type of tank, thoroughly wet the fiberglass surface for only 2 minutes using RustBlast. Drain and rinse well with water as directed. Because you are not prepping metal or dissolving rust, RustBlast may be saved and re-used for future use. RustBlast will, however, treat the fiberglass surface by giving it a more acidic pH level and by leaving a zinc phosphate coating ideal for Sealer adhesion.
Also, it is important to make sure that the tank is completely dry inside before sealing. Drying is best accomplished by introducing forced air into the tank by using a shop vac, blow dryer, or fan. (NOTE: Drying is a critical step for sealing fiberglass tanks. Fiberglass tends to hold moisture and if the tank is not dried completely, the Sealer will not adhere properly.)
IMPORTANT: It is also very critical to methodically coat the entire fiberglass tank completely and thoroughly with the Sealer. If any part of the fiberglass surface should accidentally be left exposed or unsealed, however, these unprotected areas will be very susceptible to deterioration by alcohol blended fuels and it is therefore highly recommended that these fuels not be used in fiberglass tanks even after sealing. After coating the tank, remember to drain well to avoid pooling and puddles.
NOTE: In the unlikely event that you would have any troubles with the KBS Tank Sealing Process, we have our KBS Fix-It Guides Available HERE. It is always a great idea to familiarize yourself with these guides before you begin your project.
Frequently Asked Questions — KBS Gold Standard Tank Sealer
Have a question about sealing your tank? Find the most common answers below, or order your Tank Sealer Kit and get started today.
Yes. Tank Sealer works on both metal and fiberglass tanks. The process is nearly identical, with one difference: in Step #2, apply RustBlast to the fiberglass surface for only 2 minutes instead of the standard 30–60 minutes, then rinse and dry thoroughly.
Fiberglass holds moisture, so the tank must be completely dry before sealing — use a shop vac, blow dryer, or fan to introduce forced air. Any remaining dampness will prevent proper adhesion. Also be sure to coat the entire interior thoroughly — any uncoated area will be susceptible to deterioration from alcohol-blended fuels.
Allow 96 hours for maximum cure before refilling with fuel. Always test the tank with water first before adding gasoline.
Do not place the tank in direct sunlight or near a heat source to speed up curing — this can hinder adhesion rather than help it. Allow the tank to air-dry naturally in a well-ventilated area away from direct sun and heat.
No. Gold Standard Tank Sealer is capable of bonding to and permanently sealing remaining rust or corrosion after proper prep. What is critical is removing all loose, flaky rust during Step #1 with KBS Klean — use a flashlight to inspect the interior and repeat cleaning until all loose rust is gone.
RustBlast in Step #2 neutralizes any remaining active rust and leaves a zinc phosphate coating that provides the ideal adhesion anchor for the sealer. A white powdery residue after drying is normal and beneficial.
No. You must completely remove the old coating before applying Tank Sealer. Applying over a failed or existing liner will cause the new sealer to fail as well.
Tank Sealer is a single-coat application. Pour the entire contents of the can into the tank, then rotate and roll for up to 30 minutes to coat all interior surfaces evenly. Pay particular attention to weld seams and pinholes.
After thorough coating, drain all excess sealer completely until it no longer drips. Then rotate the tank side to side every 5 minutes to prevent pooling. Foaming or bubbling is a warning sign of excessive accumulation — drain thoroughly or the sealer may fail to adhere and eventually break loose.
The ideal application temperature is 55°–82°F (13°–28°C). Apply only in moderate to dry atmospheric conditions — avoid sealing in rainy or humid weather.
Tank Sealer is a moisture-cured urethane. If it cures too quickly due to high humidity, surface bubbling can occur as a result of gas entrapment beneath the top layer. Always allow the tank and all products to reach room temperature before beginning.
No. Proper tank sealing requires removing the tank from the vehicle so you can rotate, roll, and fully drain the sealer from all sides. You will also need to remove all fittings — floats, sending units, and filters — and seal all openings with high-quality duct tape before starting Step #1.
For pinholes and small exterior weld seam repairs, use KBS BackBone Reinforcing Mesh embedded in a thin layer of Tank Sealer painted on the exterior. Apply another thin coat over the mesh, painting outward from the center, and let cure.
For holes larger than a pinhole, use KBS NuMetal Epoxy Putty. Allow NuMetal to cure for 12 hours before proceeding with sealing the tank interior. After sealing and draining the inside, use any remaining sealer to paint a thin coating over the patched exterior area for reinforced coverage.
Drain all excess sealer until it stops dripping, then rotate the tank side to side every 5 minutes to prevent accumulation in any single area. This is especially important in tanks with baffles or designs that make complete draining difficult.
Yes. The KBS 3-Step System works on aluminum tanks. Follow the standard process: KBS Klean for degreasing, RustBlast to etch the surface and leave a zinc phosphate adhesion coating, then Tank Sealer. Rinse thoroughly after RustBlast and allow the tank to dry completely before sealing.
Use KBS #1 Thinner for immediate cleanup of tools and any accidental spills. Tank Sealer cannot be removed by any solvent once cured, so act quickly before the product dries.
Always wear protective gloves to avoid skin contact and temporary staining. If skin contact occurs, remove immediately with #1 Thinner followed by soap and water. Place any drained leftover sealer in the open can with the lid off and let it harden — do not replace the lid before curing is complete, as pressure can build and pop the lid.
Still have questions? Contact us for technical assistance.
