Originally Posted by Halfbrit
... Did you use the "hand-full of drywall screws" mentioned in Caswells instructions to rough up your tank? was it effective?
I did not - I didn't want the screws banging up the vent tubes.
It seems to have had excellent adhesion regardless.
I did use a thorough cleaning procedure.
I did not use acetone - I think you would want to be cautious with Acetone on your finished paint, so removal will be tricky.
I used water with few drops of detergent initially - shook up tank really well and then rinsed several times really well
Finally used alcohol to remove any residual water and then left my heat gun blowing warm air through it to throughly dry.
Did you use masking tape or duct tape to cover all the openings? How soon did you remove it after coating?...
I did - actually several iterations during the process.
Best method I would say is - seal the filler neck and the level sensor port (I used a bung for the latter);
Pour resin mix in through the pump port and move around to coat tank, while avoiding position which will spill onto pump plate opening (or just go ahead and seal initially). It helps to have the pump plate port 'open' because you can see what you are doing. But of course will have to seal it up when you come to coat the area in that proximity.
Then use brush (as necessary) to 'paint' into some of the corners or the vent tubes, accessing through the pump plate opening;
then re-mask across the pump plate opening and continue to rotate tank to cover the areas close to the pump plate.
You can probably remove the tape after about 30 mins or so and trim up the edges of the openings as necessary with a blade, while it is still slightly soft.
If you have excess material, you can always remove it - although somehow I doubt you will.
Can't stress enough that it should be warm in the area you are working to ensure that it will flow.
I'm sure I would do this better the second time around!
If you have no plans to repaint the exterior, be sure you protect the paint adequately - especially if working inside the tank (with brush) you want to be sure you do not touch the exterior if you have any on your gloves - change gloves frequently. I would suggest you wrap tank with seran wrap so there is no danger of touching it with 'sticky fingers'.
Here are Caswell's own instructions:
Originally Posted by Caswell Plating
All traces of oil and gasoline should first be removed by pouring about 1 pint of acetone or lacquer thinner into the tank, and rotating the tank several times to thoroughly sluice the sides with solvent. Dispose of the contaminated solution.
When recoating your gas tank from failed Kreem or POR-15 tank sealers, remove the old, failed coating using a paint stripper containing Methylene Chloride.
Place a hand full of drywall screws into the tank and shake them around vigorously for several minutes. These will dislodge any loose particles of rust. In the case of Fiberglass and plastic tanks, this will rough up the tank interior, improving adhesion.
Rinse out the tank with about 1-pint of acetone or lacquer thinner, then set aside and allow to dry. Use an airline to blow air into the tank to aid drying.
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. Mix up the required amount of Gas Tank Sealer (one unit should treat two small motorcycle tanks or one large one) If you are only treating ONE small tank, then divide parts A & B in half. You could use a dipstick to gauge this.
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. BAD MIXING AND BAD MEASURING IS THE #1 CAUSE OF FAILURE!!
Pour into the tank, then immediately seal up the filler hole with Gladwrap and an elastic band. Swill 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.
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.
Scrape off any excess with a sharp knife at this point (usually about 40-60 Min after mixing) Place the tank in a warm 70-90 f place and allow to cure overnight. In the case of alcohol fuels, allow 3-5 days at room temperature, or 24 hours at 120 deg f.
Originally Posted by frider
Wonder.... Would it reduce the tank capacity by much, d'ya think?????
It will reduce the capacity by EXACTLY the volume of material that you pour in. Whole thing is 1 pt (US)