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Ethanol, “Fuelish Thing” Indeed

by Jim Bounds
Orlando, Florida

So you're driving along in your GMC motorhome, the world whizzing past and your mind content in the knowledge that this 26-foot “piece of heaven” is powered by your thoughts and dreams of having something truly unique and, best of all, yours. Scanning the array of gauges tells you all is well with the power plant. The steady steering wheel tells you the coach is taking that considerable torque to the road with style. Then there is an event!

The vacuum gauge starts to loose numbers, the coach seems to loose life, too; there is a shudder and a loss of power. Sitting up fast in the seat, you mutter to yourself: “What’s wrong, Baby?” After it knocks the cruise control off there is another shudder and you, again, have some power. You think: “What was that?” And now you start on your methodical investigation.

Pushing the pedal, you find at some point you loose power again. Backing off, you get it back again. As you crest the small hill the coach, again, seems fine but you know in your heart there will be further repercussions. You tell yourself: “We are in status mode. All levels report any anomalies immediately.” Now the saga begins.

If anything like this has ever happened to you understand that you are not alone. As our vintage rides further age, we are all doing our best to stave off the effects of deterioration due to age, wear and many other factors. To that end we should carry with us a certain amount of paranoia and prepare for as many possible issues as we can. Some "on the road" issues can be nipped in the bud by preparation and periodic, preventive maintenance. Others need a good dose of understanding so when something does happen you can quickly asses the situation and find the root issue without lost time and overdue expense.

Some issues in which we must guard ourselves are things that happen due to road conditions or things over which we have no control. Still, others we can foresee. One such issue has to do less with our coaches, their age or condition and more with the changing times.

Oil and fuel formulations have undergone huge changes trying to deal with the EPA on emissions. In the past our government watchdog agency has removed the lead from our fuels in an effort to clean up some of the bad stuff pumping out the exhaust. The engineers said this would destroy our older motors from within -- it didn't and we all were able to give those folks a laugh. Unfortunately, it also gave us a false sense of security. We discounted the notion that our government would do anything with our vital fluids that would prevent our beloved mechanisms from doing their best. Then they took ZDDP out of our oils and we did get a jolt. There was a negative response from our machines and we scrambled to protect ourselves and our babies from those effects. Then something sinister happened, without fanfare, our government mandated the use of Ethanol into our fuel supply. For whatever profit-oriented reason may have been behind that move we now have “10% or less Ethanol” in much of our fuel supply. Hey, that does not sound that bad. Ah, but that’s what you think!

OK, so they found some new liquid to make our fuel less of what it was and to still charge us more -- it's the way of the world. Beyond that the curve is steep in the process of adapting our coaches, with their big-block, American motors, to this ethanol compound. What is this stuff?

Ethanol is primarily comprised of water and alcohol; great cleaning agents. On the surface one might say: “Hey this is good stuff. It will clean up our act.” The question is, however, what does it clean out and where does it send the bad stuff.

A decade ago, the EPA was preparing for this lacing of our fuels for many reasons. They were preparing for a future of less green house gases and all. Fuel stations were mandated to replace their old rusty, leaking fuel tanks. We all saw many gas stations dig up their driveways to install new plastic-looking tanks and all. That was part of the preparation. The problem is that ethanol will dislodge rusty stuff from old tanks and send it directly to the motor. I think they saw that coming and tried to do away with those fungus-covered vessels. Maybe they knew it would clog up filters and maybe damage motors, maybe they didn't. For whatever reason they exposed us to some possible issues having to do with these particulates floating around in the underground tanks at gas stations.

No matter how squeaky clean you keep the fuel delivery system in your coach, the gas that is pumped into your tank could be tainted. Sure, the gas stations are supposed to have filters to stop this but, for whatever reason, that safeguard is not working and you need to be aware of this.

If your fuel tanks have not been cleaned out in a coons age, don’t worry, they’ll need to be shortly because it will be your turn to pull to the side of the road and exclaim: “What the heck happened!” The materials suspended in your fuel will be extremely fine and the filter that will be affected will be the one in front of your carb if it does stop it at all. If not, prey that this fine graver passes through your carburetor because usually it will clog it up and leave you sitting still. I'm not talking about the big filter you put in the line, it will be the one that is the last defense up in the front of the carb itself, the one with tiny holes. The WIX part number for this filter is 33052. My suggestion is you pick up 2 or 3 of these things and know how to change them.

Eventually, as the nation's gas stations blow all of their junk into our vehicles and our vehicles gulp it down and pass it through our waiting filters, down the tiny passages of our carburetors, through the intake and exhaust valves and out the tail pipes, we'll be shed of this issue. But, as I said, we have a bunch of stuff to swallow before we get there and this issue clears up. Some parts of the country instituted the addition of Ethanol a couple of years ago and they are past that curve, this is how I feel we can see the track record of where the rest of us are going.

None of this will change the fact that our fuels will now have a lower boiling point or that we will not get the mileage we enjoyed before Ethanol came to our fuel supply -- no, we will be forced to just live with that. Many folks out west have experienced fuel actually boiling in their tanks from the heat given off by the black asphalt on a hot, sunny, desert day. Insulating the underside of our fuel tanks and the fuel lines up to the carb will, hopefully, guard us from this situation.

The performance issue is a bit more complicated. We need to really keep our old power plants in tiptop condition. Two MPGs can make a huge impact on our wallets so we need to spend the time and bucks to keep everything in as efficient condition as possible. If you are getting bad mileage, do something. If you don't your wallet know the fuel must be going somewhere -- out the tailpipe means you are bleeding out money. If the unused fuel is finding it's way past the pistons or valves into your crankcase and the oil lubricating your motor, the tainted oil will not be doing it's best to keep your motor moving smoothly and you might find yourself lunching your dingle box! The benefit of keeping your motor in good working condition and getting as much as you can out of this "lousy gas" we are now forced to use will become more an issue as fuel costs inevitably increase.

So, it is a “fuelish thing” to go along as before, not protecting yourself from the oil and fuel supply we are now using. “The times, they are a-changing” so you need to roll with it and keep yourself and your coach safe from the bad effects of these changes. I check the carb filter of every coach that makes it's way onto my lot. I do this not just to help keep my customers safe but also to track the level of effect the ethanol is having on our vintage machines. Let me tell you, many people were on the verge of having, as Houston would call it, “A situation”. Help yourself, change out your carburetor filter, maybe install an additional fine mesh filter (not just any in line filter) and keep your motor running well. Who knows, maybe the motor Gods will shine down on you a few more years!

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Additional comments by the webmaster

In Summary

While E-10 isn’t the best fuel choice for our motorohomes, there are some ways to deal with it. Being armed with the facts will help you cope.

Ethanol is alcohol. Alcohol attracts water. It mixes infinitely with water. Once mixed, the alcohol and water stay mixed. This is because both alcohol and water are “polar”. This means they have electric charges that cause attraction to each other.

Gas is generally considered electrically neutral, or “non-polar”. Left to itself, gas won’t hold much water in suspension, it’ll separate (which is why gas floats on water). Small amounts of ethanol can be dissolved into gas to make E-10, but it is not permanently bound into the fuel. As your motorhome sits, especially in warm, highly humidity climates, the gasoline literally absorbs moisture from the air. As the ethanol draws moisture into the fuel the water attaches itself to the ethanol and the mix separates from the gas. Once the fuel’s total water level exceeds about .5%, the water/ethanol mix separates from the gas. This is where the problem really becomes obvious. The performance of the fuel will degrade. Fuel economy will drop and cold starts will become noticeably difficult. The engine will idle poorly and run roughly. Acceleration will be non-existent in some situations. The engine will be more susceptible to ping and knock under acceleration and can ruin the engine eventually.

Another thing about the ethanol/water mixture is that it makes a great paint stripper. As such, it breaks off old varnish, gum, and resin that has been deposited by years of gasoline sitting in the tanks. This sticky goo plugs filters, sticks up carburetors and severely fouls the injectors causing everything from mild drops in performance to complete engine shutdown.

What to Do

  1. If you haven’t had your original tanks cleaned inside or replaced, plan to get this done.
  2. Replace old fuel lines, o-rings and gaskets that aren’t rated to work with ethanol.
  3. Routinely inspect hose clamps and any metal fittings in the fuel system for signs of corrosion.
  4. Keep your tanks as full as possible to diminish the airspace in the tank, which will reduce the amount of condensation.
  5. Use fuel additives that will stop fuel aging and oxidation, and will protect octane and other ignition characteristics of the gas.
  6. Use fuel additives that clean injectors and don’t contribute to carbon deposits on valves and pistons.
  7. Don’t use a fuel additive that emulsifies water. Water is not a component of fuel. By intentionally putting water in your fuel you may harm your engine.
  8. Never buy fuel that is not clear and bright.
  9. After sitting for the winter, add a combustion-enhancing additive to restore octane qualities of the gas.
  10. Do not leave a near-empty fuel tank sitting for long periods of time. Drain it and fill it with fresh fuel before driving more than 25 miles.

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