Autogas Tips and Tricks

"tony roberts" wrote in message
news:indiacharlieecho-3078EB.21441326042007@shawnews...
Here in Canada, friends who fly with Mogas use Chevron - they tell me it
doesn't contain alcohol.
Our government is threatning to add ethanol to pretty much all gas next
year.
Aircraft Spruce sell an alcohol testing kit.
I believe that it separates out the alcohol - so that you can drink it -
but I could be wrong

Tony
--

Tony Roberts
PP-ASEL
VFR OTT
Night
Cessna 172H C-GICE

Ugh! That gives added meaning to "rot gut"!

I can not find the reference at the moment, so will not mention the source;
but I seem to recall that adding about 10% water to the fuel, agitating it,
and letting it settle will cause the water/alcohol mixture to be
precipitated. Presuming that my recollection is correct, that still leaves
three problems: 1) disposal of the contaminant, 2) unknown performance
number of the resulting fuel, and 3) increased cost of material and labor.
Fortunately, if the volume of alcohol is nearly as great as the volume of
water added, the contaminant could possibly be burned as a means of
disposal.

Obiously, an effort to change legislation so that contaminants are no longer
added to gasolene would be a better long term solution.

Peter

"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

In article . com,
"Robert M. Gary" wrote:

On Apr 27, 6:06 am, Orval Fairbairn wrote:
In article .com,
"Robert M. Gary" wrote:





Al wrote:
With 100LL now creeping toward the $5 mark (or more), it's time to
take advantage of the Peterson autogas STC in our 172E. 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.

Thanks in advance.

Al
1964 172E
KSFF

Find someplace where the autogas mixture is not prohibited by the FAA.

-robert

That would be everywhere in the USA. As long as you have the appropriate
STC's and mogas, you can mix avgas and mogas to your heart's content.

Which STC allows for mogas with alcohol? I've called EAA on this and
they said they are not aware of any. The FAA is concerned that the
seals in the fuel system will break. Besides, I've seen what this new
mogas has done to my weed-eater. The local mower shop is backed up 45
days in repair cleaning out carbs trying to get this cruddy gas out.

-Robert

Robert,

You didn't ask about mogas containing alcohol -- you asked about
mogas/avgas mixing. You are correct that alcohol and aviation hoses,
seals, fibreglass tanks, etc. are, at best, an iffy proposition and are
not approved.

Boat operators, for instance, are having problems with alcohol attacking
fibreglass fuel tanks. It decomposes the resin (probably polyester) and
deposits goo in fuel filters, carburetors, etc.

In fact, there is a problem if you run petroleum-based fuel and switch
to parrafin-based fuel, or vice-versa. The neoprene hoses acclimate to
the fuel in use and harden when another type is introduced.

This phenomenon is probably the cause of a rash of vehicle fires in the
1990s in California, when MTBE was introduced to fuel there.

On Apr 27, 12:42 pm, Orval Fairbairn
wrote:

You didn't ask about mogas containing alcohol -- you asked about
mogas/avgas mixing.

I pointed out that the mixture that the refineries are using generally
prohibit the resulting mogas from being used in aircraft. I never said
anything about mixing avgas with mogas.

-robert

"Ron Natalie" wrote in message m...
: It more closely matches the 80 your O300 was designed for
:
: Only in octane perhaps. It still has more than twice the lead.
:
: There is an advisory for the O300 about vapor lock and the CPA
: recommends flying only on one tank anytime above 5000' so you can easily
: clear the lock.
:
: That recommendation comes from Cessna itself, and has nothing to do with
: auto fuel.

I thought it was an AD. My 172A fuel selector is placarded to do this.

Blueskies wrote:

I thought it was an AD. My 172A fuel selector is placarded to do this.

You're correct. It was an AD (not a recommendation from Cessna) and the
placard was required on affected models.

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

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

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

Mike Isaksen wrote:

I was talking to the Rotax guys (Lockwood or similar) and they mentioned the
same "ethanol up to 5% is OK" number. I got distracted and never asked the
followed up question re the problem that most east coast states typically
blend at 10%. Anyone heard or has any actual experience of running 10%.

It's more than just the engine. One of the problems with running ethanol
is that it may react with fuel system components that were not designed to
handle it. The engine manufacturer has no control over what goes into the
hoses, tanks, fuel pump diaphrams, etc...

That's the big problem with ethanol in most older aircraft. Ethanol wasn't
a factor when the fuel systems were designed and built in the 60s and 70s.
Ethanol can melt or swell some of the components used in those systems.

When I started using ethanal mogas in my old '69 Merc, I had composite
floats that turned to goo, and a couple of 1/4" rubber lines swelled up like
hot dogs.

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

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

In fact, there is a problem if you run petroleum-based fuel and switch
to parrafin-based fuel, or vice-versa.

Isn't paraffin just part of petroleum product? Mogas, avgas and jet-A
are all largely paraffinic. Mogas nowadays have a fairly high
aromatics content.

"Orval Fairbairn" wrote

Boat operators, for instance, are having problems with alcohol attacking
fibreglass fuel tanks. It decomposes the resin (probably polyester) and
deposits goo in fuel filters, carburetors, etc.

In fact, there is a problem if you run petroleum-based fuel and switch
to parrafin-based fuel, or vice-versa. The neoprene hoses acclimate to
the fuel in use and harden when another type is introduced.

I had a problem with 10% alcohol fuel, back around 1988, when I filled up
twice in a row, with the alcohol fuel, in a 34' Pace Arrow motor home.

Halfway through the second tank, it started to run at about half power.
(not enough power to pull a good sized hill)

Long to short, after much hair pulling, I discovered that all of the varnish
accumulated in the fuel system for thousands of gallons, and 10 or so years,
was suddenly dissolved, and then deposited in the big canister type fuel
filter.

I would think that even if the fuel hoses and O-rings and such were alcohol
safe, that this type of problem could be very likely to happen in an
airplane.
--
Jim in NC