We’ve had a couple of questions related to additives. I don’t know exactly how long after Ford put America on wheels the first products popped up laying claims to cure what ails your car, extend its life, improve performance, reduce fuel and oil consumption just to name a few but it couldn’t have been to long. Without looking too hard I found this ad from the SC Johnson company advertising its Car Savers, from the wax most know them by, to a carbon remover treatment.
Because there are so many different fluids and so many flavors of additives for those different fluids we’re going to break them down by system. Up first fuel additives.
Fuel additives are usually marketed in four basic flavors, fuel line anti-freeze/water remover, fuel system cleaners, fuel stabilizers, and octane boosters.
Heet is likely the best known anti-freeze/water remover. Does it work? Absolutely, all products sold as fuel line antifreeze, are all or almost all alcohol. The alcohol mixes with the water and allows it to mix with the gasoline. Is it needed or beneficial? It depends on a couple of factors. In much of the US what is sold as “gasoline” at the pump contains some alcohol, up to 10%. So if you use gas containing ethanol you’ve got more than enough alcohol in the tank already.
So what if you use un-adulterated gasoline? That depends some on the car. Until the 70’s direct venting of fuel tanks were the norm. So the normal expansion and contraction with temperature changes meant a lot of air was exchanged, increasing the opportunity for condensation to occur. Then the EPA brought evaporative emission controls into the picture. The early systems at a minimum forced the tank to breathe through a long hose greatly reducing the air exchange. With the advent of OBD-II systems it’s a closely controlled system all but eliminating air entering the tank. So it is likely unnecessary in modern cars, for most drivers, but for your Curbside Classic it may be indicated depending on climate and the fuel in your area.
Fuel system cleaners, these also go way back, though of course at the beginning they were sold as carburetor cleaners. Gumout is one that goes way back and is probably the best known. Do they work? Certainly many formulations do, though this is a crowded segment and undoubtedly the effectiveness will vary from brand to brand. The active ingredient is some type of solvent, naphtha is a common choice and many contain some type of oil along with an often small amount of their proprietary chemicals. Is it needed or beneficial? Fact is that since the mid 90’s there have been minimum fuel detergency standards in place in the US. That ethanol added to some gas is also a good solvent. So again for most drivers in most modern cars there really isn’t a need. But for your carb equipped Curbside Classic who’s fuel bowl is vented to the atmosphere an occasional or regular dose is likely a good idea.
Fuel stabilizers. This one that many Curbside Classic owners are likely to consider when they put it away for the sometimes long winter. Fact is fuel does go bad with age. It actually oxidizes and the different components can evaporate at different rates. With gas containing ethanol it can degrade in as little as 3 months. Looking at the MSDS for a number of them show that the common components are oils from “light” to “heavy”, naphtha, and a usually small amount of their particular proprietary component. The reasons given why they work range from that they are an anti-oxidant, to that they contain a more volatile compound that becomes that “target” of the oxidation process.
Hey wait a minute……..the components of the fuel system cleaners and fuel stabilizers seem pretty similar….hmmm.
Yup and you’ll find a number of products that claim to both be fuel system cleaners and fuel stabilizers, even if they are primarily marketed as for one or the other. The products that are primarily sold as stabilizers tend to have a thicker base than the cleaning products. In my research for this I noted that some people indicated that the products that use a heavy oil base sometimes seemed to leave their own residue. Others have noted good results using a product marketing as a combo cleaner/stabilizer for long term storage.
Octane Boosters. Many claim to make racing fuel out of ordinary pump gas. They seemed to take off with the intro of “low-lead” and reduced availability of extreme octane fuels in the 70’s. Do they work? Most brands have proven to raise the octane but it usually is an expensive way to get octane. If your car starts to ping after filling up at a questionable station it might provide what is needed to run that batch out. If you’ve got an old school super high compression engine and the race gas you normally use isn’t available then a couple or 3 bottles may be just the ticket. For the most part however fixing the underlying issue or changing your tune/set up to accommodate the fuel available would be more cost effective in the long run.
I mentioned gasoline containing ethanol a couple of times so we should probably discuss that since it certainly could be considered a fuel additive. I don’t want to start the debate of why it’s good/bad so hopefully we can stay away from the political side, there are lots of other sites to debate politics. Fact is some cities and states have mandated some or all fuel be E10, some metropolitan areas have year round or seasonal “oxygenated fuel” (E5.75%), other areas may contain anywhere up to E10 despite the lack of a State, Local, or Fed mandate.
Just to make it more confusing are the individual state’s labeling laws. It varies from prohibiting noting the presence of ethanol, others allowing it but not requiring it, to states that require at least a sticker containing words to the effect “may contain up to 10% ethanol”. So you may have to do a little research to see what exactly it is that you get from your local pumps. But knowing what you are putting in the tank of your car especially your Curbside Classic.
Now I’m not a chemist nor do I play one on TV, so if there are any chemists out there and can shed some more light on these products speak up. Have you had a particularly good or bad experience with fuel additives? Never used one in your life? Let us know.