Autogas Tips and Tricks

[Al[_2_]]

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

[[email protected]]

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.

Trick number 1, find autogas without alcohol in it these days.

--
Jim Pennino

Remove .spam.sux to reply.

[Newps]

You operate exactly the same way.




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

[Helen]

As mentioned, the ethanol thing is a problem. Cessna Pilot's
Association recommends using a 50/50 mixture of 100LL and auto fuel in
your O300. It more closely matches the 80 your O300 was designed for
than anything else out there. I did until I moved to an ethanol state.
After moving and having to burn state 100LL I discovered the joy of
stuck valves. Now I add MMO or TCP to the expense of 100LL.

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.

I got the EAA STC. It was $145 for my O300 C172F. No work to it other
than the paperwork and sticker application.

You'll find a lot more advice on this on the CPA forum: www.cessna.org
Calling the CPA tech guys is also a good thing.

Oh yeah, MoGas also voids the warranties on cylinder overhauls and such.
Of course the MMO alternative voids that and potentially your
insurance as well. You just have to decide if you'd rather have a
warranty or a working engine.

Helen

PS. There's good reading about MoGas STCs on the EAA page.


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

[Orval Fairbairn]

In article >,
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

In my plane, if I have been flying, then let it sit on a hot ramp, I
have to apply the boost pump to get the overcome vapor pressure.

Everything is fine for flight -- as long as there is air flowing through
the engine compartment.

[Jim Stewart]

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.
>
> Trick number 1, find autogas without alcohol in it these days.

All the folks driving the Rotax 100hp engine
are using 91 octane mogas with about 5% alcohol
with no issues. I have no idea whether or not
that would be acceptable in a Lycoming or Continental.

[Robert M. Gary]

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

[Orval Fairbairn]

In article >,
Jim Stewart > wrote:

> 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.
> >
> > Trick number 1, find autogas without alcohol in it these days.
>
> All the folks driving the Rotax 100hp engine
> are using 91 octane mogas with about 5% alcohol
> with no issues. I have no idea whether or not
> that would be acceptable in a Lycoming or Continental.

Watch out if you have fibreglass tanks! Boaters are finding out (the
hard way) that the alcohol decomposes the resins into goo that gums up
carburetors, filters and lines.

[Mike Isaksen]

"Jim Stewart" > wrote...
> wrote:
>> Trick number 1, find autogas without alcohol in it these days.
>
> All the folks driving the Rotax 100hp engine
> are using 91 octane mogas with about 5% alcohol
> with no issues. I have no idea whether or not
> that would be acceptable in a Lycoming or Continental.

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%.

[[email protected]]

Jim Stewart > wrote:
> 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.
> >
> > Trick number 1, find autogas without alcohol in it these days.

> All the folks driving the Rotax 100hp engine
> are using 91 octane mogas with about 5% alcohol
> with no issues. I have no idea whether or not
> that would be acceptable in a Lycoming or Continental.

Depends on whether you're talking "acceptable" from a practical
or legal position.

From a practical standpoint, alcohol has a number of bad effects
on things not designed to be exposed to it, and unless you know
the effects of alcohol on every little piece in your engine, you
just became a test pilot.

From a legal standpoint, probably not a snowball's chance in hell.

--
Jim Pennino

Remove .spam.sux to reply.

[tony roberts]

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


In article >,
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

[Robert M. Gary]

On Apr 26, 9:00 pm, Orval Fairbairn > wrote:
> In article >,
> Jim Stewart > wrote:
>
>
>
>
>
> > 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.
>
> > > Trick number 1, find autogas without alcohol in it these days.
>
> > All the folks driving the Rotax 100hp engine
> > are using 91 octane mogas with about 5% alcohol
> > with no issues. I have no idea whether or not
> > that would be acceptable in a Lycoming or Continental.
>
> Watch out if you have fibreglass tanks! Boaters are finding out (the
> hard way) that the alcohol decomposes the resins into goo that gums up
> carburetors, filters and lines.- Hide quoted text -
>
> - Show quoted text -

The FAA has never issued any STC's allowing for

[M[_1_]]

On Apr 26, 7:47 pm, Helen > wrote:
> As mentioned, the ethanol thing is a problem. Cessna Pilot's
> Association recommends using a 50/50 mixture of 100LL and auto fuel in
> your O300. It more closely matches the 80 your O300 was designed for
> than anything else out there.

50/50 mixture will give you closer to 91/96 Avgas. 25% 100LL/75%
autofuel mixture is closer to 80/87 in terms of TEL level.

> 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.

I run straight autofuel in a low wing Grumman all the way up to 12,500
feet and I didn't have any vapor lock problem.

The situation most prone to vapor lock is a short turn-around stop on
a hot day. You shut down, fuel up or loading/unloading, and fire up
again. The fuel line in the engine compartment can get very hot. The
way around this problem is to open up your cowling to let the heat out
during those quick turn stops.

[RST Engineering]

Robert, please go away. Your incessant obsequiousness to the FAA is
becoming irritating to those of us who want practicality in our lives.

Jim




"Robert M. Gary" > wrote in message
oups.com...

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

[Ron Natalie]

> 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.

[Peter Clark]

On Fri, 27 Apr 2007 06:51:11 -0400, Ron Natalie >
wrote:

>> 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.

And AAUI only applies to the older Cessnas without dual venting caps.
New Cessna aircraft don't have the instruction, and IIRC even the
older ones don't have to if they've installed the newer style venting
caps on both tanks. Wasn't there an AD or something to do just that a
number of years ago?

[Orval Fairbairn]

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.

For experimentals, it is a matter of engine compatibility.

[ArtP]

On Fri, 27 Apr 2007 04:44:24 GMT, tony roberts
> wrote:

>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

When searching for auto gas with less than 10% ethanol I looked at
Chevron. They specifically state there gas should never be used in
aircraft. (I never did find auto gas with less than 10% except in Ha
which is just too far from Md to do me any good.

[Ron Natalie]

Peter Clark wrote:
> On Fri, 27 Apr 2007 06:51:11 -0400, Ron Natalie >
> wrote:
>
>>> 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.
>
> And AAUI only applies to the older Cessnas without dual venting caps.

It's up to and including the K model. But it's not the caps, it's a
vent line. The cap issue is a different AD.

[Robert M. Gary]

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

[Peter Dohm]

"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

[Bob Fry]

>>>>> "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

[Orval Fairbairn]

In article om>,
"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.

[Robert M. Gary]

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

[Blueskies]

"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.

[JGalban via AviationKB.com]

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

[JGalban via 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

[JGalban via 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

[M[_1_]]

>
> 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.

[Morgans[_2_]]

"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

[Peter Clark]

On Fri, 27 Apr 2007 11:28:20 -0400, Ron Natalie >
wrote:

>Peter Clark wrote:
>> On Fri, 27 Apr 2007 06:51:11 -0400, Ron Natalie >
>> wrote:
>>
>>>> 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.
>>
>> And AAUI only applies to the older Cessnas without dual venting caps.
>
>It's up to and including the K model. But it's not the caps, it's a
>vent line. The cap issue is a different AD.

Ah, I stand corrected. Thanks.

[Jay Honeck]

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"

[Cubdriver]

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.

[Cubdriver]

On Fri, 27 Apr 2007 22:24:33 GMT, "JGalban via AviationKB.com"
<u32749@uwe> wrote:

> 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...

As it was told to me, this is the problem for the Cubs.

[Bertie the Bunyip[_3_]]

Cubdriver <usenet AT danford DOT net> wrote in
:

> On Fri, 27 Apr 2007 22:24:33 GMT, "JGalban via AviationKB.com"
> <u32749@uwe> wrote:
>
>> 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...
>
> As it was told to me, this is the problem for the Cubs.
>

You can immunise your cub from the ravages of auto fuel by doing th
efollowing..

1, Make sure your float is metal and not cork. Cork floats are pretty
rare nowadays anyway, but some of the ingredients of modern fuels wil
melt the varnish on the float and that's not good.

2, Your float needle seat should be metal, not plastic. Shouldn't be a
problem for your carb, but it's best to make sure just in case someone's
"modernised" it or you have a later type carb in your airplane.

3. Change your hoses to automotive type. I put aircraft type fittings on
auto fuel line I just got at the local auto parts store. 14 years on and
many gallons of auto gas later, no problems.

Your old continental will really appreciate you not sticking 100LL into
it. No fouled plugs, no sticking valves. I do put Marvel Mystery oil
into the engine for a few reasons, though. Aside from being a good
lubricant for the valves, it also keeps corrosion at bay when the
airplane's sitting.


Having aaid all of this, I haven't run it on any gas containing ethanol
yet. I might try it as I can't realy see any problem for my engine, but
I'll do a good bit of research on it before I do. I'm fortuante in
having as an acquantence a petro-chemical engineer who is also a pilot.


Bertie

[Jay Honeck]

> 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 Masino]

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

[john smith[_2_]]

In article om>,
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.

[Blueskies]

"john smith" > wrote in message ...
> In article om>,
> 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....

[Orval Fairbairn]

In article >,
"Blueskies" > wrote:

> "john smith" > wrote in message
> ...
> > In article om>,
> > 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.

[Blueskies]

"Orval Fairbairn" > wrote in message
...
> In article >,
> "Blueskies" > wrote:
>
>> "john smith" > wrote in message
>> ...
>> > In article om>,
>> > 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.

Thanks!
And that means that all testing has been done using 87 "octane" mogas and the engine operated completely normally with
no new or additional operating limitations.

Cubdriver said "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." This issue is likely a
mis-adjusted engine mixture or a bad carb than an issue with mogas usage...

[Bertie the Bunyip]

On 1 May, 04:25, Orval Fairbairn > wrote:
> In article >,
>
>
>
>
>
> "Blueskies" > wrote:
> > "john smith" > wrote in message
> ...
> > > In article om>,
> > > 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.

Well, not exaclty, the A65 and it's predecessors were designed before
WW2 and in any case weren't designed for the military market, but
there wasn't much difference in Avgas and autogas at the time anyway.
The Cont. A-40, 50 and 65 were all designed with a min octane rating
of 73, which required no lead whatsoever to achieve. Their compression
ratio is sop low they don't get hot enough for the various ingredients
of higher lead fuels to digest the mix properly, resulting in deposits
on the plugs and valve stems gumming up the works anyway. 100LL has a
considerable amount of lead in it still (about 4X the amount 80/87
has) and these engines don't like it one little bit.
Of course, you can always dump a little Marvel Mystery oil in there,
which not only lubes the top end, it helps burn off deposits...
MY old Le Blond is rated for 60 Octane fuel! I'm checking into the
viability of running it on carrot juice..


Bertie

[nrp]

The OP asked about using MoGas & this has turned into a discussion
dissing Ethanol laced fuels (which should be dissed).

But if you get a candidate auto gasoline, it can be easily tested to
make sure it isn't adulterated by ethanol. Mix 1 part of water with
about 10 parts of sample gasoline in a test tube, shake for a couple
of minutes, and see if the apparent water level has increased. If
not, it does not contain alcohol.

Trying to remove alcohol with water is suicidal. The resulting octane
number is lowered creating the possibility of a detonation related
engine failure.

If your state has mandated ethanol for autos, look for an alternate
source such as marinas or other specialty pumps. One problem with
E-10 fuels is an engine will only deliver about 95% of full horsepower
on the stuff. There is a long term hose compatibility problem &
possibly the accelerator pump & needle-and-seat in the carb bowl will
give trouble. The needle tip may not be compatible, and if it sticks,
you might have an engine failure. Your float should already have been
changed back to metal if all the carb ADs have been complied with.
Your tanks are metal too. There are elastomeric seals in your fuel
selector and primer, but I got 20 years of autofuel use out of my 172M
without seal service or any other difficulty.

Some will argue the vapor pressure of autofuel is higher (yes it
generally is). But you don't have a fuel pump and your gravity-based
Cessna fuel system is quite resistant to vapor lock. Your 172's
brothers have a rare fuel delivery problem that is mystery-based &
that's why the placard for single tank above 5000 ft msl has been
added. This problem was encountered back in the days of never-use-
autofuel-or-you-will-crash.

Actually the vapor pressure difference between autofuel and AvGas is
alternatively eaten up by only about a 15 degreeF fuel temperature
difference. Where is the rule saying you can't paint your wings black
(vs cooler white)? Fuel delivery systems that are marginal on
autofuel will usually be marginal on AvGas too.

Starting will be a little different - particularily if your aircraft
has been sitting for weeks. On shutdown, I first shut off the fuel &
run the carb bowl empty if the plane is going to sit more than a
couple of weeks. It does make restart simpler.

Occasional use of 100LL might help the exhaust valves - or it may be
an old wives tale. Many do say breakins of a new or fresh majored
engine should involve some leaded fuel.

Your plugs will easily go 100+ hours without cleaning. Your oil will
not get gray from lead in the blowby.

You might want to install an EGT as it seemed to me that my engine ran
slightly leaner with autofuel. I found the fuel consumption of
autofuel is slightly less. I think it weighs very slightly more per
gallon.

Autofuel does not cause warts or hemorrhoids (sp?).

[Cubdriver]

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

[Matt Whiting]

Cubdriver wrote:
> 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

Were the buying the mogas in small quantities frequently or in a large
tank infrequently? It is quite well-known that mogas has a summer blend
and a winter blend (or blends in some areas). The winter blend has a
higher RVP. If you burn summer auto fuel in cold weather, you are
asking for trouble. I ran mogas in my Skylane for 6 years in fairly
cold northern PA winters and never had a "quiting" problem. I had only
a 50 gallon tank so I typically bought the fuel on the way to the
airport so it was always both fresh and in season.

Matt

[RST Engineering]

If you got gasoline in season and you bred it, could you get litters of
gasopuppies?

Jim


"Matt Whiting" > wrote in message
...


I had only
> a 50 gallon tank so I typically bought the fuel on the way to the airport
> so it was always both fresh and in season.
>
> Matt

[Matt Whiting]

RST Engineering wrote:
> If you got gasoline in season and you bred it, could you get litters of
> gasopuppies?

No, you would get liters. :-)

Matt