Kreem Super Sealant

Kreem Super Sealant

EVALUATION

Kreem

Tank sealer can be useful stuff, especially in the case of a steel gas tank with rust inside. Getting rust out of a tank is difficult, if not impossible-we've never found an effective or easy way to do it. Leaving the rust in may be fine for awhile, but in advanced cases the rust can plug petcock strainers or prevent the float needle from seating in a carburetor.

In theory, a gas tank sealer covers the inside of the gas tank with a tough, plastic coating that seals off the rust already in the tank and prevents new rust from forming. The sealer is poured into the tank in liquid form, then sets up. Several coats are usually required for a complete, long-lasting seal.

The trouble with the theory is that there are tank sealers on the market today that have serious flaws. Like taking days to set up, even when the tank is warmed by a heat lamp. Or being only “fuel resistant” when the buyer reads the fine print on the can.

When you’re in a hurry to seal a tank and use it again, slow-drying sealant which may or may not dissolve when the tank is filled with gasoline just isn’t confidence inspiring.

Fortunately, there is a tank sealer that does what it is supposed to do with minimum hassle. Kreem Super Sealant is gasoline proof, dries reasonably quickly and solved a rusty-tank problem on the Cycle World endurance road racer entered in the 1980 AFM Six-Hour.

The bike had been run in the 1979 SixHour, and in preparation the gas capacity was enlarged by welding together two stock gas tanks. The problem started when we pulled out the stored big tank for this year’s race. The inside surfaces were coated with rust, and rust flakes appeared when we washed out the tank with solvent.

No way did we want rust flaking off for the duration of the six hour race—that possibility sounded too much like an invitation to DNF.

Kreem sealant comes in pint cans, which sell at local shops in our area for $5.95 each. (If your dealer doesn’t stock it, he can order it from Flanders Co., a motorcycle parts and accessory distributor).

It takes one pint of Kreem to coat three gallons of gas tank capacity, and our endurance tank held eight gallons, so we bought three pints.

After washing the tank out with solvent and allowing it to dry overnight, we pulled the petcock out of the gas tank and covered the opening with duct tape (first using contact cleaner on the surfaces the tape had to stick to). Then, outside the garage (the sealant should be used in an open area since the fumes are very strong and very flammable), we poured in the three pints, molded aluminum foil around the gas cap opening and used safety-wire around the tank filler neck to hold to foil in place.

We then slowly rotated the tank in every direction, so that the sealant inside would flow over the internal surfaces. That done, we drained the excess sealant through the petcock opening (by pulling off the duct tape). In doing so, we discovered that the sealant will remove paint—splashed sealant damaged the paint on the tank, which, since the tank had a crummy paint job anyway, was no big deal. But for riders with paint finishes they’d like to keep nice, care must obviously be taken.

To promote drying (the race was only two days away), we laid the tank on one side on a chair and positioned a floor fan right in front of the gas cap opening. When the fan was turned on, we could feel a steady, slight flow of air coming out of the petcock hole, so we knew that the fan was circulating air through the tank. Air circulation helps the sealant dry quickly.

The next day, we repeated the steps. Twelve hours after the last application of sealant, we filled the tank with high-octante racing gas and qualified for the six hour. After finishing the race—and spending a weekend in direct contact with racing fuel—the sealant was in perfect condition, isolating the gas from the rust and adhering to the tank inside surfaces.

Kreem tank sealant contains rust inhibitors, and the manufacturer claims it will seal hairline cracks and pinholes in gas tanks as well as coat rust. We can’t say anything about its performance as a cure for leaks, but it works fine for controlling rust.