Gas Tank Sealers

[bmh]

From Wikipedia;
"Dry gas is an alcohol-based additive used in automobiles to prevent any water in the fuel from freezing, or to restore combustive power to gasoline spoiled by water. The name Drygas is actually a brand name, owned by Cristy. It is a liquid that is added in to the fuel tank, that absorbs the water and keeps it in solution."

Seems to contradict the dept of commerce. I also did not see the term hygroscopic used in the physical description of alcohol, though many products seem to claim that it is so and for a fee they will sell you the cure ( for a problem that doesn't really exist). We use alcohol as a mild cleaning solvent at work, and my observation is that an open container of alcohol will evaporate faster than it pulls water out of the air, even in the most humid conditions. Chemically speaking when you add water to alcohol you get a solution, no mater the proportions of the two. The resulting solution is still alcohol, just a lower "proof". Distilleries add water to alcohol all the time to adjust the proof for bottling. Ever see a bottle of Jack Daniels separate? Once the proof of the alcohol gets low enough it will behave more like water and freeze more easily, be more reluctant to burn, etc. But that would require a great deal of water. When I was involved in road-racing years back, we used to add 10% racing alcohol to our proprietary fuel blend to help keep the other 4 ingredients from separating.

The water that winds up in fuel tanks, if not let in by a leaky cap , is usually formed from condensation in the air space in the tank. That process happens whether or not the fuel contains alcohol or not. Hence the advice to keep your tank full. This is not to say that alcohol is harmless to our old machines. To the contrary, it poses plenty of hazards such as dry rotting rubber lines for one. But i don't believe it is a serious contributor to "tank rot". To the contrary it is probably helping to eliminate the problem.

[indianut]

let's put the nasty rumor that increased alcohol content leads to increased water or moisture in the fuel or the tank to rest. This is just modern marketing hype that preys on peoples lack of knowledge to sell them products they don't need and that probably don't do much. Water in your gas is almost a thing of the past because of the alcohol. Remember something that removed water from fuel called dry-gas? It was nothing more than denatured alchohol.

absolutely untrue!

[ricmoran]

FYI, POR 15 is actually a Moisture Cure Urethane, which means the stuff loves water, and the more of it the harder it works.

If you use POR 15 or it's competing product CORTEC VpCI 396 Mositure Cure Urethane (difference between POR 15 and CORTEC's product is CORTEC 396 contains aluminum particulate and Vapor phase Corrosion inhibitors and can be applied to mildly rusted metal surfaces, if galvanizing is done insure to use CORTEC VpCI 373 micro primer for best results) insure humidity is at least 65% or better for proper curing of the coating. if the humidity is below 65% your going to end up with problems with either coating.

Once these coatings cure, the pencil hardness goes up quite a bit and flexibility goes down along the way. If the coating cracks, CORTEC has a leg up as the coating employes VpCi so rust will have a difficult time gaining a toehold, and if your ethanol based fuel goes sour and water develops, both coatings work hard to protect the surfaces they have been applied to. With VpCi in the mix, undercutting is staved in a big way, without it, any coating will over time allow undercutting to occur and ultimately coating failure by delamination occurs.

Downside, is both products use either tolulene or xylene which are extermely hazardous to your health and if used in an enclosed unventilated space & can cause a potential explosive issue. Since motorcycle gas tanks are small, chances are slim anythign could happen, but with winter coming up I would not use these in my basement or shop without excellent ventilation as where an electric or gas heat system is present can cause potential ignition of the vapors if these accumulate in a dead space.

Always were a respirator when using these products as inhalation can cause headaches and worse, one could have a reaction to the chemical later in life.

I use the CORTEC product as we distribute it. We have been in the corrosion control business for many years and have found the moisture cure urethane products to be terrific coatings to use with difficult corrosion prone projects.

Last point is that these products are succeptible to UV and will chalk/yellow with age if exposed, but the performance is not hampered in any way.

[exeric]

I have to state that with the tank I am fixing, leaving the tank unsealed is NOT an option. I have to use a sealer. I started this thread to get first-hand data from people who have used and experienced the performance of different gas tank sealers. New and un-rusted tanks are a different animal and probably should be left alone, but trying to rescue, and use seriously neglected tanks presents unique problems. I was hoping some of the Cannonball participants would chime in with their gas tank solutions because their empirical experiences would be something you could take to the bank.

Brian, use a thick paint remover to get the old Kreem out of your tank. You can buy a gallon of the nastiest paint remover on the market for less than a gallon of MEK and you will use less of the product, it will stick to the walls, floor, and ceiling of the tank, and will not leak out of the pin-holes like a thin solvent. Use the MEK to flush the residual paint remover and sealer.

[exeric]

Let's put the nasty rumor that increased alcohol content leads to increased water or moisture in the fuel or the tank to rest. This is just modern marketing hype that preys on peoples lack of knowledge to sell them products they don't need and that probably don't do much. Water in your gas is almost a thing of the past because of the alcohol. Remember something that removed water from fuel called Dry-gas? It was nothing more than denatured alchohol.

Brian, with the introduction of high content ethenol fuel in Florida, the problem of tank rot and carburetor problems have become a major factor for antique vehicles. I can assure you this was not a big problem in Florida 10 years ago. Maybe it's exacerbated by Florida humidity, or maybe Florida is getting the worst gasoline in America.

[ricmoran]

Not sure how this works, there are user reports listed for the motorcycle tank sealing compound kit:

http://www.kbs-coatings.com/Tank-Sealers_c_7-1-0.html

[23JDCA 808]

What rating is the "high content ethenol fuel in Florida"? E15 ?
Here is a site that lists ethanol-free gas stations around the U.S. http://pure-gas.org/

[exeric]

What rating is the "high content ethenol fuel in Florida"? E15 ?
Here is a site that lists ethanol-free gas stations around the U.S. http://pure-gas.org/

Thanks for the link Bill. This morning I filled my tank with ethenol free gas at the only listed station in Sarasota. It may be my imagination, but my Chief ran so well I took a long ride along the beaches. We are also having perfect weather today so that may have been a big factor in why I think it's running so well.

[rwm]

if you look at the list for pa. you will see all the stations are in the less populated area of the state. in the center of pa your car does not need am emissions test and that is where all the ethanol free stations are.

[junkyarddog]

Aviation Fuel

If you want trouble free fuel, find a small airport in your area and get some 100 octane low lead fuel. I can buy it here for $4.00 a gallon. I run it 100% in all my grand kids dirt bikes. The shelf life is almost forever so bikes that don't get run everyday don't have problems with carbs gumming up. I also so run at least 50% mix in my street bikes.
The airport I go to has a pump available 24hrs a day with a card so I even ride in and fill up.
I take a couple 5 gallon can to get fuel for the dirt bikes.
Try it, you'll like it and so will your bikes.
Jim
PS: Of course 110 racing fuel is even better, but it is about $7.00 a gallon

[bmh]

Eric, I have some aviation grade stripper, we'll give it a shot. Have you visited a local marine supplier? Boats often have custom made fuel tanks made of fiberglass and resin. They may know of a product that while not a "sealer", may work for you such as ISO poly resin or something.

[exeric]

I pressure tested the tank this afternoon and found a few pinholes I missed. When I find a pinhole, I open the hole and dimple it in to accept a .060" flathead brass rivet. I use tinning flux and 50-50 solder to solder the rivet to the parent metal of the tank. I just started using an antique copper soldering iron that has to be heated with a torch and it is by far the best way I have found to lead solder anything; far better than an electric soldering iron. The tank is now structurally sound and leak free but after cleaning the inside with diluted acid, followed by a baking soda bath, and lacquer thinner; I've got a light coating of new rust. I have spent a lot of time sandblasting the inside of this tank to get it rust free; so to say I'm a bit P.O'd would be a gross understatment. I'm doing all of this to have a clean, rust free, oil free surface for the sealer to bond too. Most of the sealers on the market say it's okay to aply the sealer over "some" rust provided the inside of the tank is clean, dry, and prepped with solvent. I don't trust that and want to eliminate any trace of rust before I pour in the sealer. Again, I'm fishing for some good advice and real experiences.

[koanes]

Eric, All I can add is what I learned at the Denton Meet in NC back in May. I spent the better part of 3 days there and payed special attention to what was going on with the guys selling a rust removal product called Evapo-Rust. It is a thin semi-clear liquid that does a very clean job of removing rust. The sellers recommended a water rinse and the use of acetone or similar to remove any moisture before sealing. The recommended sealer was Red-Cote. I spoke with friend and highly regarded metal and paint man Larry Medwig, he uses Red-Cote sealer. He recommended thinning the material and applying two coats. He mentioned the slight red tint to the gas initially, but said he has had no problems with the sealer breaking down.

[exeric]

Thanks Kyle. I used Red-Kote today and it looks like it's going to bond quite well. I did a test on a piece of clean, but rusted metal and it bonded very well. I'm going to use Larry Medwig's method of doing 2 thinned coats.

[yhprum]

White vinegar will do a good job of removing rust, if you can wait. And its not expensive.