Modern fuel blends containing ethanol are eating classic cars from the inside out. Here’s what you can do to protect yours.
By Jeff Huneycutt
Like they say, “It’s the things you don’t see that you’ve got to watch out for.”
Sort of like when you are buying a new car and then get hit with all the fees the salesman never mentioned until you are signing the paperwork. That’s sort of what is happening with the fuel you use.
A few years ago, when ethanol began being blended with gasoline, we were told how it’s good for the environment, how it helps reduce our dependence on foreign oil and how it will benefit the American farmer. After all, in the U.S. ethanol is created from corn, and what could be better than corn, right?
But ethanol also has some very serious drawbacks that weren’t mentioned at the time. Namely, ethanol is hygroscopic, which is just a fancy term meaning that it attracts water. Ethanol exposed to the atmosphere will actually pull the moisture from the air and attach to it. Having water in your fuel system is bad enough on its own since it is pretty useful at putting out fires instead of helping combustion, but it gets worse. The water and ethanol are actually corrosive to many metals and actively harm components in the typical fuel system. That’s why many auto manufacturers now build and market cars and trucks as “Flex Fuel” vehicles. That doesn’t just mean that they can burn E15 and E85 ethanol-blended fuels—practically any vehicle can do that—it means that the manufacturer has taken extra steps to protect the fuel system from the harmful effects of ethanol.
So is ethanol really that damaging? Yes! Consider that most of the gasoline used in the United States is delivered to terminals through pipelines. But the ethanol isn’t blended into the fuel until later. That’s because the ethanol is so damaging that the pipeline companies won’t allow it into their equipment. They simply don’t want the ethanol eating away their pipes from the inside out.
The same corrosion that damages fuel pipelines happens in your hot rod, classic car and even your daily driver if it was built before 2007 or so. The water and ethanol reacts to both aluminum and zinc, two of the primary components in the alloy carburetors are made from, to eat away the material and leave behind white scaly deposits. Those deposits create the perfect trifecta of bad: loss of performance, fuel mileage and reliability.
To make things worse, the damage taking place happens unseen inside the fuel system, hidden from you. And the rate of corrosion can also vary depending on a few factors. The big one is how much ethanol is in your fuel. Obviously, E85 (85-percent ethanol) fuel will corrode your fuel system faster than E10 (10-percent ethanol), but neither is good. And it looks like the percentage of ethanol used in the gasoline you can buy will only be going up. Recently, the United States Supreme Court denied a motion to force the EPA to hold off on bringing E15 to market because it isn’t being properly labeled so that consumers can avoid it. And none other than the American Automobile Association (AAA) says studies have shown that even vehicles rated as E15 compliant can be damaged by the high ethanol content in the fuel. In fact, AAA is warning its members that under no circumstances should they try to use E15 in boats, planes, motorcycles, small engines and older cars because it is so damaging. Unfortunately, it may soon become quite difficult to purchase gasoline that doesn’t have high levels of ethanol.
The second major factor regarding rate of corrosion is how long the car is allowed to sit. Believe it or not, ethanol isn’t as damaging to a daily driver as it is to a car that is only driven occasionally and allowed to sit for long periods. It’s that prolonged contact that can really do the damage. Knowing all this, it’s easy to see that classics, hot rods and other older cars that are normally only driven on weekends and during nice weather are most susceptible to the perils of ethanol. And a car allowed to sit over the winter is especially at risk. Ethanol-blended fuels are also particularly tough on marine, or boat engines, small engines like lawn mowers and power generators, and motorcycle engines.
Since ethanol began showing up in fuels, a multitude of quick fixes have popped up claiming to cure the problems ethanol creates. All you have to do is make a trip to your closest auto parts store to see the incredible variety of products now on the market. Almost every single one, however, claims to work by changing the fuel, either by somehow “removing water” or as a “fuel stabilizer.” The problem with this method is that by changing the fuel to achieve one goal, the additive may also change it in other ways that you cannot know. The fuel’s octane may be moved either up or down the scale, the vapor pressure may change, the idle may get rough, or any number of things might change that affect the way the fuel burns. This normally isn’t an issue for your average weed whacker or low-RPM grocery getter, but it can harm the performance of a highly tuned engine. Any additive that changes the chemistry of the fuel can affect the proper tune-up for the engine in ways that are very difficult—or even impossible—to predict.
Understanding this, Driven Racing Oil™ has found an alternative solution to the problem. Driven’s history is in racing, and not just the NASCAR Cup Series. Driven also has extensive experience racing with Sprint Car and Modified teams running methanol alcohol as the fuel, and for years those teams have dealt with the same issues hot rodders are now seeing with ethanol. Driven’s chemists and engineers know what works and what doesn’t, and its solution to the ethanol issue is a great departure from the rank-and-file products already on the shelves. Driven Racing Oil’s new Carb Defender additive doesn’t affect the fuel but instead creates a sacrificial barrier between the carburetor (and other fuel system components) and the ethanol.
“We’re racers and engine builders,” explains Driven’s Lake Speed Jr., “so we understand the need for protecting an engine’s performance. When we set about looking for a solution to help engines with ethanol corrosion, we looked to find the right balance. We wanted to provide superior protection without affecting the fuel. Our answer with Carb Defender is actually to create a metal deactivator. The molecules in our additive have what you might call a preference for aluminum, zinc and other materials. It creates a chemical barrier that keeps the fuel from oxidizing with the metal and protects your fuel system without affecting performance.”
Speed says Driven’s research shows that for hot rods or older cars driven fairly regularly, Carb Defender needs to be added to the fuel only every other fill-up or so. But even for a car that’s only driven irregularly, maybe on nice weekends or to the occasional car show, adding a bottle of Carb Defender each time you hit the pumps will still be able to provide proper protection. The tiny 4.5 ounce bottle is highly concentrated so it can treat a 25 gallon tank without diluting the fuel. It also works as a cleaner to dissolve and break up oxidation deposits; just mix one bottle for every eight gallons for the first tank and then bring the treatment back down to normal levels.
“At Driven, our primary business is high performance motor oils, and we’re pretty successful at it,” Speed says. “We saw the ethanol problem from being involved in motorsports ourselves and also from engine builders we work with. If we thought that there was a viable product already available to help with the problem we would have simply told people, ‘Hey, use this.’ But there just wasn’t anything that we thought worked to the standard we thought it should. So that’s why we are producing Carb Defender. Like racers and hot rodders, we’re engine guys first, so we looked for the molecule that fit the problem. Unlike a lot of chemical companies, we didn’t start out with a prized chemical and then look around trying to find a market for it.”
But Speed is also quick to say that because Carb Defender is designed specifically not to affect the fuel, it also won’t cure an excessive buildup of water drawn into the fuel because of the ethanol. “This is a phenomenon known as ‘phase separation’ which happens when the ethanol draws enough moisture from the air that the water actually separates from the fuel,” he explains.
“Phase separation is most likely to happen in situations where there is lots of humidity in the air, when the fuel and air temperature is warm, or when there is a lot of surface area for the air and fuel to meet. So if you are driving around on a warm day in an area where it’s humid and with a half tank of fuel, that’s when the fuel is drawing the most moisture. You park the car with the half- tank so there is a lot of the fuel’s surface area exposed to air in the tank, and that ethanol really starts pulling in the moisture. Then when the fuel cools—just like air—it can’t hold the moisture as well as when it is warm and it falls out of suspension as drops of water. Water is heavier than gasoline so it gathers in the bottom of your tank, which is exactly where your fuel pump pickup is located.”
Imagine how hard it is on your engine when you hit the starter and the first thing it gets is a shot of water instead of fuel. If you’ve ever put your car into storage for the winter running great and then had trouble getting it to start the next spring, you may have been a victim of phase separation. The good news is Speed says the best cure for phase separation is mechanical, not chemical. So you can do it yourself rather than spending your hard-earned money on more product. The key is to limit any opportunities ethanol-blended fuel may have to interact with air.
Since most of us don’t have easy access to ethanol-free fuel, we have two real-world options for eliminating phase separation and the problems that come with it. One option is to always drive the car until the fuel tank is empty, or drain the fuel tank every time you store your car. Then, put in fresh fuel when you are ready to drive again. This, obviously, isn’t realistic so we’ll scratch that one and move on to option two.
This time around, instead of running the car out of fuel before storage, top the tank off on your way home so that it is absolutely full of fuel when you park it. A fuel tank must be vented, so you can’t totally cut off access to the atmosphere, but by filling the tank to the top you move the contact area for air and fuel to interact up from the fuel tank to the filler neck, severely limiting the opportunity for ethanol to pull moisture from the air. Since you have to buy fuel anyway, the fix doesn’t cost anything, and combined with Carb Defender you can allow your car, boat, motorcycle or anything else to sit all winter if necessary and still have confidence that it is fully protected from harmful ethanol. And when you do bring it back out of storage, it will run just as well as the day you parked it. That’s the Driven advantage.
Learn More About Carb Defender™