Keeping fuel costs down

by Stephen R. Smith

Nov 7, 2010



I love to fly and have logged 892 hours in 3 and a half years. That’s a lot of fuel.


I have never liked the lead in aviation fuel. It trashes the spark plugs and the engine oil and of course it’s bad for the environment. My 601’s Jabiru 3300 engine does not need the lead.


A few months ago I started burning premium automotive fuel. I bought two plastic 14 gallon fuel tanks from Costco for about $80 each. The gas tank comes with a long hose which has a gas station-like nozzle on the end, which I cut off and discarded.


On my way to the airport I stop at the Chevron station and buy up to 28 gallons of gas. I set one tank on each wing walk and run the hose out to the filler opening and let the gas drain into the wing tanks while I preflight the plane. It’s a bit of a hassle but not too bad and I save a lot of money.


Today I tried something different. I put 5 gallons of premium in the pilot’s-side tank and 14 gallons of regular in the passenger’s-side tank. I almost never have a passenger so I tend to put more fuel in that side.


I took off using the premium fuel then throttled back and switched to the tank with regular fuel. I kept the RPMs below 2,500 at all times and flew most of the time at about 2,200 RPM. CHTs were generally below 300. The engine ran just fine.


At 2,200 RPM my 601 is going about 80 miles per hour while burning about 3.3 gallons per hour. That
works out to about 25 miles per gallon. Not bad at all. Using regular automotive fuel the cost per hour is under $11.


All automotive fuel sold in California contains 10% ethanol. The Jabiru motor’s stock Bing carburetor comes with white colored floats which turn to mush over time when exposed to ethanol. The white floats need to be replaced with black colored ones. These are available from Bing.


The only issue I have encountered due to ethanol is that the Zodiac’s gas caps are made of a plastic that is not ethanol resistant. They are getting a bit gummy and are now hard to open and close. I have not found replacements for these yet.


Steve


  • Louis W. Ott

    There are quite a few locations where you can get unleaded gasoline without ethanol. Here is a web site you can check. Click on the list of states to check availability in your state. Some of the octane listings are wrong so double check the octane at the station.

    http://pure-gas.org/index.jsp?stateprov=OR

    Nov 7, 2010

  • John Ellis

    I use 93 octane auto fuel regularly since I run a Soob auto conversion. It has ethanol in it so I'm careful with the carb heat and have not had any trouble (yet). The major advantage to the higher octane is slower burn and less chance of detonation if it is running lean. I can't remember if bing carbs are altitude compensated. If not, you may want to be careful at higher density altitudes when running lower octane. Another consideration is that octane dissipates over time, so an 87 left in the wing can be much lower if not used.

    I too use plastic cans but now use a ground strap. The plastic can pick up quite a charge just with air blowing across it. Sitting on a painted wing does not provide a good ground path, not like the filler hole. You may want to ground the cans to a clean surface. There are many documented incidents related to static and ungrounded plastic cans burning up airplanes.

    John

    Nov 8, 2010

  • Dr. Edward M. Moody II

    I have a local source for ethanol free auto gas through one of my EAA chapter members. That's all I use now.... it's 93 pump octane or about 96 - 97 RON and I have had no problems with it at all. Early on, for the first 35 - 45 hours I bought local Murphy gas station premium gas and honestly, I wasn't seeing any problems with that either but decided that avoiding ethanol completely AND getting the fuel delivered to my hangar in bulk (I have a 200 gallon steel fuel storage tank and pump in the hangar) was way too convenient to turn down. It ends up costing me 10 - 15 cents per gallon more than Murphy prices but I just don't get to fly enough to hurt my budget at that cost.

    Ed

    Nov 8, 2010

  • Mack P. Kreizenbeck

    Steve,
    I'm going to Costco!
    You said something about changing the floats ought to cure the problem of alcohol damage.
    This sounds good up to a point as I understand the Bings can be damaged (pitted) internally by allowing ethanol to sit in the bowls for any period of time. I picked this info up from a motorcycle group. Maybe some more research is needed to verify!! Phillips 66, here in Idaho, advertises "no alcohol" in their fuels. Do you have any 66s in California?
    Keep up the good work,
    Mack

    Nov 10, 2010

  • Stephen R. Smith

    Hello Mack,

    I am reasonably sure all gas sold for cars in California contains ethanol. Ethanol is the replacement for MTBE which was previously added to gas to "oxygenate". MTBE is carcinogenic.

    It may be that Ethanol will corrode some fuel system parts. I am saving enough money to replace the entire carb from time to time if necessary; probably not going to be.

    Steve

    Nov 11, 2010