7696 Route 31 Lyons NY 14489 USA
http://www.caswellplating.com
315-946-1213 Fax 315-946-4456
GAS TANK SEALER
Application Instructions
READ THIS COMPLETE INSTRUCTION SHEET BEFORE STARTING
Preparation
1. All traces of oil and gasoline should first be removed by going to Step 2 for plastic tanks or Step 3 for metal tanks. If you should decide to use
acetone when doing a fiberglass or plastic tank use extreme caution. Do not allow solvents to stay in the tank over 10 minutes. Dispose of
the contaminated solution. Allow to dry.
2. For Plastic or Fiberglass tanks: wash the tank with Dawn Dish Soap, Hot Water and the drywall screws. These will rough up the surface. Rinse with
Hot water and allow to thoroughly dry then go to step 5.
3. For Metal tanks place a hand full of drywall screws with about a pint of acetone or lacquer thinner into the tank and shake them around vigorously for
several minutes. These will dislodge any loose particles of rust, and in the case of plastic/fiberglass, rough up the surface. Dispose of the
contaminated solution. Allow to dry.
4. ADDITIONAL STEP FOR ALUMINUM TANKS: Add two tablespoons of LYE (Drano) to one gallon of water. ADD LYE TO WATER, NOT WATER TO
LYE. WEAR PROTECTIVE GEAR. Slosh the solution around in the tank for 30 seconds. Pour solution out and dispose. Rinse with water and pour
off. Add 8oz of vinegar into a quart of water and slosh around in tank for 30 seconds. This neutralizes the lye. Pour off and rinse with water. Allow to
dry.
5. Apply duct tape or masking tape to any weeping seams, holes or porous areas. This will stop any Gas Tank Sealer from oozing out, and will allow it to
bridge over the hole. Plug the outlet ports with putty or Play-Doh.
6. If the tank has a good paint job, protect it from resin spillage by coating with THREE coats of Caswell Seal Mask masking liquid. This paints on and
then peels off. For extra protection, you can cover with cling film, then aluminum foil, then another layer of cling film.
Mixing
BAD MIXING AND BAD MEASURING IS THE #1 CAUSE OF FAILURE!! USE ONE KIT PER TANK
Mixing ratio is 2 parts of A to 1 part B. Gas Tank Sealer resins should be at room temperature. Store your resin and gas tank at room temperature for 12-24
hours before mixing, so that it is at the correct temperature. Resin colder than 70oF will make resin thick and not flow well, hotter than 85 oF will make it runny, so
it doesn’t stick to the sides well and it will cure too quickly. The tank and the resin should be at the same temperature. If the tank is hotter than the resin, it will
cure the resin faster, reducing your working life and coverage. Resins stored in a garage that is 90°F, used at that temperature, would HALF the working time or
worse. At 70°F, the material will have gelled in 30 minutes, so it is important to have wetted the tank walls with the sealer within 10-15 mins of mixing.
Mix up the required amount of Gas Tank Sealer (Coverage will depend entirely on the total surface area of the tank, not the volume)
There is NO relationship of volume to surface area, ie: Tank: 12”x 12” x 12” = 7.48 gals = 864 sq inches
Tank: 12” x 144” x 1” = 7.48 gals = 2040 sq inches
IT IS NOT RECOMMENDED TO TRY TO USE THE KIT TO TREAT TWO SMALLER TANKS. MOST FAILURES OCCUR FROM IMPROPER MEASURING
AND MIXING. DO NOT mix anything less than HALF UNITS! You may apply a second application within 24 hours if you want to use up the resin. This is, of
course, good insurance on a bad tank, or one with many baffles etc.
In a separate plastic container (margarine tub etc.) mix the two parts together thoroughly for at least 2 minutes. Scrape around the sides to ensure all resin
is blended together. Apply the sealer IMMEDIATELY after mixing completely. Waiting 5-10 mins will reduce your working time and coverage rates, as the resin
will have already started to cure.
In the event that the viscosity is too thick from working in higher temperatures which is inevitable, you can add a small amount of Xylene or lacquer thinner
to the mix (no more than 5% - i.e. 1 fl oz in the motorcycle kit, 2 fl oz in the car kit). This serves to retard the cure cycle and thin the sealer somewhat
to allow easier coating coverage. This is also advisable if you plan to split the sealer between two tanks.
Application
1. Pour into the tank, then immediately seal up the filler hole with GLADWRAP and an elastic band. Rotate the tank around in every direction for several
minutes to obtain a good layer of Gas Tank Sealer over all surfaces. Remove the filler cap, GLADWRAP seal, and pour out any excess. Allow to
drain upside down for a few minutes.
2. If you have a built in fuel filter, blow air into the fuel line port for about 10 minutes. This will clear the filter of any Gas Tank Sealer.
3. Trim up any excess material as soon as the Gas Tank Sealer becomes plastic like. This can be scraped out with a sharp knife at this point (usually
about 40-60 Min after mixing) Place the tank in a warm 70-90 o F place and allow to cure for 24-36 hours before putting gasoline in the tank.
4. If you want, or need to apply a second coat, you must do so while the first coat is still tacky (usually within 24 hours)
5. If you can elevate the temperature of the tank to 140 of for 4 hours, this will ‘post cure’ the resin and the tank may be put into immediate service.
Care
Avoid the use of fuel additives that contain Methylene Chloride (Lucas Gas Treatment), or Mineral Spirits (Marvel Mystery Oil). Sta-Bil ethanol treatment is ok to
use. If in doubt, avoid.