Autogas Tips and Tricks

"PD" == Peter Dohm writes:
PD but I seem to recall that adding about 10%
PD water to the fuel, agitating it, and letting it settle will
PD cause the water/alcohol mixture to be precipitated.

There's a guy I know who does this. Sounds suicidal to me just to
save a few bucks.
--
A man's only as old as the woman he feels.
Groucho Marx

Al wrote:
What are the
tips and tricks for operating with mogas. Different run-up
techniques? Taxiing, hi temperatures, vapor lock avoidance, winter
ops. You name it. Inquiring minds want to know.


Operationally, it's the same. In addition to the standard cautions about
avoiding ethanol tainted mogas, you should also get your mogas from a source
that has a relatively high turnover. This time of year is when most vapor
lock problems show up. It's because the refineries are switching from their
winter blends, which vaporize much easier in cold, to the summer blends. If
you fill up with winter blend on a hot day, you could experience vapor lock.


John Galban=====N4BQ (PA28-180)

--
Message posted via http://www.aviationkb.com

What are the
tips and tricks for operating with mogas. Different run-up
techniques? Taxiing, hi temperatures, vapor lock avoidance, winter
ops. You name it. Inquiring minds want to know.

No tricks. No special procedures. In fact, you can run your engine
far more normally than you can with 100LL, without fear of lead-fouled
plugs.

We just ticked over 8,000 gallons of mogas through our O-540-powered
Pathfinder, pumped through this rig:
http://alexisparkinn.com/new_mighty_grape.htm

The $$$ just keep adding up... Just keep lobbying your state
legislators to NOT mandate ethanol-polluted gasoline in your area.
--
Jay Honeck
Iowa City, IA
Pathfinder N56993
www.AlexisParkInn.com
"Your Aviation Destination"

On Thu, 26 Apr 2007 19:09:16 -0700, Al
wrote:

Taxiing, hi temperatures, vapor lock avoidance, winter
ops. You name it. Inquiring minds want to know.

Our Cubs were STC'd for mogas for a year or so, then went to 100LL.

The big problem was the instructors didn't like the smell, especially
the woman instructor. But the men weren't far behind. It certainly
stank, compared to 87 or 100LL. And in a Cub the instructors of course
sat in the front seat where the dribbles were.

More serious for me, sitting in the back seat, was that the engine was
prone to quit. The worst moment was flaring on landing, when the
airstream stopped driving the prop, the prop stopped driving the
engine, and the engine stopped. Most pilots claim that the engine runs
better on mogas, but this was not my experience.

The airport instituted a rule that we couldn't fly the Cubs when temps
were below 20 degrees F, and that helped some.

Now I use the mogas pump to buy fuel for my small engines, since it is
the only way to get gas without alcohol. The airport buys it buy the
truckload at the marine terminal in Portland ME before the alky goes
in.

Our Cubs were STC'd for mogas for a year or so, then went to 100LL.
SNIP
More serious for me, sitting in the back seat, was that the engine was
prone to quit. The worst moment was flaring on landing, when the
airstream stopped driving the prop, the prop stopped driving the
engine, and the engine stopped. Most pilots claim that the engine runs
better on mogas, but this was not my experience.

Sorry Dan, but I can't let this lay. You are spreading dangerous and
misleading misinformation.

If your engine was quitting on final, I would have some serious
maintenance done on your Cub -- *or* I'd carefully check the quality
of your fuel. There is NO reason (as in zero, zilch, nada) for your
Cub's 1930s technology engine to run any differently on 87 octane
unleaded mogas -- a fuel FAR closer to what it was designed to use --
than it would on 100 LL.
--
Jay Honeck
Iowa City, IA
Pathfinder N56993
www.AlexisParkInn.com
"Your Aviation Destination"

Jay Honeck wrote:
of your fuel. There is NO reason (as in zero, zilch, nada) for your
Cub's 1930s technology engine to run any differently on 87 octane
unleaded mogas -- a fuel FAR closer to what it was designed to use --
than it would on 100 LL.

It's my understanding that, in addition to octane level and lead
content, autogas also differs from avgas in it's "vapor pressure".
This is why certain aircraft need modifications to their fuel systems to
use autogas (to prevent vapor lock). It may well be that, in the Cub,
you need to reroute some fuel lines, or tweak the idle, or idle-mixture,
in order for it to run properly on autofuel. This is one of the reasons
that the FAA doesn't issue blanket approval for the entire fleet to
start using autofuel.

--- Jay


--

Jay Masino "Home is where My critters are"
http://www.JayMasino.com
http://www.OceanCityAirport.com
http://www.oc-Adolfos.com

In article . com,
Jay Honeck wrote:

Sorry Dan, but I can't let this lay. You are spreading dangerous and
misleading misinformation.


Jay, just because your engine works well with it does not mean others
will. There are many variables. That is why there is an STC for each
aircraft/engine combination.

"john smith" wrote in message ...
In article . com,
Jay Honeck wrote:

Sorry Dan, but I can't let this lay. You are spreading dangerous and
misleading misinformation.


Jay, just because your engine works well with it does not mean others
will. There are many variables. That is why there is an STC for each
aircraft/engine combination.

Exactly right, and if Cubdriver used autogas with a STC then it should work as published, no issues with operation.
However, if there is not an STC then all bets are off. I would be surprised if there was not a STC for the old Cubs
however....

In article ,
"Blueskies" wrote:

"john smith" wrote in message
...
In article . com,
Jay Honeck wrote:

Sorry Dan, but I can't let this lay. You are spreading dangerous and
misleading misinformation.


Jay, just because your engine works well with it does not mean others
will. There are many variables. That is why there is an STC for each
aircraft/engine combination.

Exactly right, and if Cubdriver used autogas with a STC then it should work
as published, no issues with operation.
However, if there is not an STC then all bets are off. I would be surprised
if there was not a STC for the old Cubs
however....

The old Cubs were designed to run on WW-II "combat gas," which was the
mogas issued to run Jeeps, trucks, tanks, etc.

The STC equipment for the Cub is a clip fastened to a pushrod housing
and a note on the gas cap.

On 29 Apr 2007 20:47:01 -0700, Jay Honeck wrote:

If your engine was quitting on final, I would have some serious
maintenance done on your Cub -- *or* I'd carefully check the quality
of your fue

Sorry, but that's the way it happened, and as a result (plus the fact
that the instructors didn't like the smell) that the airport yanked
the STCs on its Cubs. They have operated on 100LL for the past two
years, with none of the quitting problems that afflicted them in cold
weather during the mogas era.

I appreciate that the experience is politically incorrect, and I knew
it would upset people. But it wasn't my experience, and it wasn't my
Cub; I was only a renter. Scores of other pilots flew the Cubs with
mogas and had the experience of engines quitting in cold weather. He
restarted it by diving at the beach.) For this airport, and its two
rental Cubs, mogas was a bad experience.

The airport still sells mogas. I buy it for all my small engines,
since this part of the state went to ethanol-diluted gasoline last
fall.

Say it ain't so, if you like. But it was so.

Blue skies! -- Dan Ford