Auto Gas STC

AggieMike88

AggieMike88

Touchdown! Greaser!
Joined
Jan 13, 2010
Messages
20,805
Location
Denton, TX
Display Name
Display name:
The original "I don't know it all" of aviation.
When someone acquires an STC to burn MoGas, is anything actually changed on the aircraft (tank, plumbing, engine wise)? Or is it mostly a paperwork update?
 
Depends on the airplane. The three I was involved in it was just a paperwork exercise, but I understand that there has to be some modifications to some airframes that are kind of pricey.
 
AggieMike88 said:
When someone acquires an STC to burn MoGas, is anything actually changed on the aircraft (tank, plumbing, engine wise)? Or is it mostly a paperwork update?
Click to expand...

The aircraft must be modified by adding the proper placards as in how much and what kind of fuels.. read the instructions in the STC. You must also modify the POH (flight manual), and carry a copy of the STC in the aircraft.

There is no equipment/parts added or removed by the STC other than the placards.
 
I found it

PA 28-160 thru 181


STC's for PA-28-140, -150, -151, -235 do not require changes to the fuel pumps or plumbing and sell for $1.50 per hp. STC's for the PA-28-160 -161, -180, -181 require modifications to the fuel system per STC SA2660CE. If you have a PA-28-140 that has been converted to a 160hp engine, then it will require the fuel system mod as well.


The Warrior II and Archer II and the 24 volt Warrior III and Archer III series are approved via STC SA2660CE for the use of 91 octane (minimum) automotive fuel. Piper Cadets are included too, the Piper Arrow however is not.


STC SA2660CE applies to the following aircraft serial numbers:


Cherokee, PA-28-160, PA-28-180

28-1761 thru 28-5859

28-7105001 thru 28-7505261<


Warrior II/Cadet PA-28-161

28-7716002 thru 28-8616057

2816001 thru 2816105

(Except 2816066)

2841001 thru 2841364

(Except 2841351 thru 2841359)

Archer II PA-28-181

28-7690001 thru 28-8690056

2890001 thru 2890205


Warrior III, PA-28-161

2816110 and on

2842001 thru 2842108

2842109 and on


Archer III, PA-28-181

2890206 and on

2843001 thru 2843414

2843203 and on


The fuel system mod for PA-28's consists of minor fuel system mods aft of the firewall and a totally redesigned fuel system forward of the firewall. The Piper installed electric pump is removed and replaced with a pair of redundant electric fuel pumps. You may run one pump or the other but when properly wired it is impossible to run both pumps at the same time. The FMS calls for one of the pumps to be activated for taxi, takeoff, climb, landing, and again for taxi. You may run them in cruise if you wish but it's not necessary to do so. The fuel system plumbing forward of the firewall consists of steel and stainless steel tubing and fittings. The tubing is bent to shape in our shop and comes to you attached to the pumps as an assembly ready to be tightened up and mounted on the firewall when you receive it.


The Warrior III and Archer III use the same pumps and plumbing as the 12 volt models however the Warrior III and Archer III being 24 volt, require additional parts and therefore more time for installation. A pair of voltage converters are used to drop the power to 12 volts for the fuel pumps. This was done to avoid having to conduct additional hot fuel tests which would have been necessary if we had opted for a 24 volt pump. The voltage converters are mounted aft of the baggage compartment on a bracket that is attached to the floor and left side of the fuselage. Wiring looms (completed in our shop) are installed in the left side of the fuselage to carry power forward to the fuel pumps, toggle switch, and circuit breakers.


If your airplane uses an electrical priming system you will still be using it but the procedure for doing so will be slightly different.


The 12 volt version of this STC requires six hours to eight hours to install. The 24 volt version for the Warrior III and Archer III takes from ten to twelve hours to install.


Be advised that the price of these systems may be higher in countries other than the United States and that these prices do not include shipping. Figure 7 lbs from zip code 68959 in the United States.


Click Here to Order
 
Tom-D said:
show me..

http://www.autofuelstc.com/autofuelstc/pa/Start_Here.html


I won't quote the EAA STC because it is basically the same.
Click to expand...
Check the PA-28 section of the Peterson site. You'll find this:

The fuel system mod for PA-28's consists of minor fuel system mods aft of the firewall and a totally redesigned fuel system forward of the firewall. The Piper installed electric pump is removed and replaced with a pair of redundant electric fuel pumps. You may run one pump or the other but when properly wired it is impossible to run both pumps at the same time. The FMS calls for one of the pumps to be activated for taxi, takeoff, climb, landing, and again for taxi. You may run them in cruise if you wish but it's not necessary to do so. The fuel system plumbing forward of the firewall consists of steel and stainless steel tubing and fittings. The tubing is bent to shape in our shop and comes to you attached to the pumps as an assembly ready to be tightened up and mounted on the firewall when you receive it.
 
I looked into this for the Cherokee 6 260 and the engine has been approved for the STC, but no one has done the airframe. I would guess the installation would be the same as the PA-28-235 with the added fuel pumps etc.

If the total installed cost was around 2k, this could pay for itself in about 2 years for the amount of flying I do.
 
OK, so I'll bring a stupid question to the table. WHere in the USA can you still get real gasoline?

Jim
.
.
.
 
tonycondon said:
iowa.
Click to expand...

Yup, driving to OSH, Iowa had three pumps... two were "real" gas no Ethanol, the Ethanol stuff was $0.40/gal cheaper.

Since my Yukon can run on E85, we used the cheaper stuff, but we also got a Check Engine light twice on the trip... ugh. I still haven't pulled the codes, but I'm sure it's a combination of lower altitude and the corn juice. Light is off back here at altitude and running our usual 10% Ethanol stuff here in Colorado...
 
weirdjim said:
OK, so I'll bring a stupid question to the table. WHere in the USA can you still get real gasoline?
Click to expand...

A list of gas stations carrying ethanol-free gas in the U.S. and Canada:
http://www.pure-gas.org/

A list of airports:
http://www.flyunleaded.com/airports.php

Several other online resources and groups that get access to it:
http://e0pc.com/
http://www.aviationfuelclub.org/

An Avweb podcast with Ken Misegades on this subject, which provided the seeds to finding the above and contains other suggestions:

http://www.avweb.com/avwebflash/news/Whatever_Happened_To_Mogas_202861-1.html
 
Last edited:
My first airplane had it, but I never used it. Too hard to get the fuel to the airplane, and a Cessna 150 needs frequent refueling. Had it been in a hangar I might have changed my tune, since that's a natural place to keep the gas cans. That said, no too many people want gas cans in their cars. The slightest unprotected drip and your car smells awful.

According to the linked site, there isn't a single source of ethanol-free gas in my city.
 
Hmmm... found a local supply of 91 MoGas off of that linked site that's finally "open to the public"... we already have large military fuel bladders and a 12VDC pump and filter system...

Currently $3.95/gal. That's damned tempting to get a way to get that to the aircraft "figured out".

Right now our airport says "no fueling" by anyone other than the FBOs, but I'm sure folks do it...

A Craigslist old beater pickup truck with a topper might be in my future. ;)

Or... that might just be a huge PITA, and not worth the effort. But 100LL is currently $4.95/gal at the self-serve. And we already have the MoGas STC...
 
tonycondon said:
yes seriously. Iowa is one of the few states that requires ethanol blended gasoline to be clearly labled. and they do not make ethanol blend mandatory. a good policy, IMO
Click to expand...

And all the politicians go there saying how good ethanol is. Why becuase they make the crap:D
Then they are on for the few states that does not mandate it.
 
The Petersen Mogas STC, at least, includes labels for the fuel cap area and an Adel clamp stamped with the STC number that goes on a pushrod tube on the engine. And that's all the Adel clamp is holding: the STC number.

As far as the C85 mod: There were some issues with the rubber-tipped float needle valve in the old Stromberg carbs reacting to Mogas, swelling and sticking and shutting off fuel flow. The STC might be addressing that. Newer needles are of Delrin. All of those needles are expensive.

Dan
 
Dan Thomas said:
The Petersen Mogas STC, at least, includes labels for the fuel cap area and an Adel clamp stamped with the STC number that goes on a pushrod tube on the engine. And that's all the Adel clamp is holding: the STC number.

As far as the C85 mod: There were some issues with the rubber-tipped float needle valve in the old Stromberg carbs reacting to Mogas, swelling and sticking and shutting off fuel flow. The STC might be addressing that. Newer needles are of Delrin. All of those needles are expensive.

Dan
Click to expand...

Alcohol does not harm any parts in the fuel system, even the rubber ones, It's the benzene and toluene..

cut 3" pieces of standard Aviation hose place them in three jars, fill one with benzene, 1 with toluene, and 1 with alcohol, see what does the damage.
 
Tom-D said:
Alcohol does not harm any parts in the fuel system, even the rubber ones, It's the benzene and toluene..

cut 3" pieces of standard Aviation hose place them in three jars, fill one with benzene, 1 with toluene, and 1 with alcohol, see what does the damage.
Click to expand...

Yeah, John Frank at Cessna Pilot's Assn has been saying that for a while now too.

He even believes that water or other injection systems are a fine solution to the removal of lead for the high-compression engines, pointing out that the military figured all of this out back in WWII.

As far as Ethanol MoGas goes, it seems no group (including EAA) is gutsy enough to go try to update their STC via flight testing. Probably because of real or perceived vapor-lock issues.
 
Dan Thomas said:
The Petersen Mogas STC, at least, includes labels for the fuel cap area and an Adel clamp stamped with the STC number that goes on a pushrod tube on the engine. And that's all the Adel clamp is holding: the STC number.

As far as the C85 mod: There were some issues with the rubber-tipped float needle valve in the old Stromberg carbs reacting to Mogas, swelling and sticking and shutting off fuel flow. The STC might be addressing that. Newer needles are of Delrin. All of those needles are expensive.

Dan
Click to expand...

OBTW,,,,,,, it's the new MA-3 carbs that have the rubber tipped needle valves, the old ones have a brass needle and stainless seat.

Now Kelly aerospace is using plastic floats needle valves, and a 1 piece venturi..

that's why you never have your old carb rebuilt by them or buy a new Precision or Kelly carb.
 
denverpilot said:
Yeah, John Frank at Cessna Pilot's Assn has been saying that for a while now too.

He even believes that water or other injection systems are a fine solution to the removal of lead for the high-compression engines, pointing out that the military figured all of this out back in WWII.

As far as Ethanol MoGas goes, it seems no group (including EAA) is gutsy enough to go try to update their STC via flight testing. Probably because of real or perceived vapor-lock issues.
Click to expand...

You must know that the vapor pressure of alcohol is much lower than standard fuel stock.

They know it too, that is why they won't try to certify it.
 
OLD carbs = marvel built or ovhld--> brass needles brass floats, .034 airjet

newer carbs= Precision built or Ovhld = 1 piece venturi, rubber tipped needles, and modified adomizer nozzles

new = Kelly built or ovhld. all that precision has plus a change to plastic floats and delron needle valve and floats.
 
Last edited:
denverpilot said:
Yeah, John Frank at Cessna Pilot's Assn has been saying that for a while now too.

He even believes that water or other injection systems are a fine solution to the removal of lead for the high-compression engines, pointing out that the military figured all of this out back in WWII.

As far as Ethanol MoGas goes, it seems no group (including EAA) is gutsy enough to go try to update their STC via flight testing. Probably because of real or perceived vapor-lock issues.
Click to expand...

guess who told him to wake up and smell the benzene.

Water injection does nothing to eliminate the need for a burn rate retardent, such as TEL, or a subsitute.
 
Tom-D said:
guess who told him to wake up and smell the benzene.

Water injection does nothing to eliminate the need for a burn rate retardent, such as TEL, or a subsitute.
Click to expand...

LOL. Cool. It's certainly an interesting problem for the folks flying the high compression ratio stuff.

Kinda weird that minority of the fleet is holding the rest of the fleet hostage to 100LL though.

The majority of us would happily take non-alcohol 91 octane if we could get it from a pump at the airport.

When folks ask me why I'm an evil person burning 100LL, I tell 'em I don't have to. It's just what's available to me most of the time. ;)
 
Ken Ibold said:
Check the PA-28 section of the Peterson site. You'll find this:

The fuel system mod for PA-28's consists of minor fuel system mods aft of the firewall and a totally redesigned fuel system forward of the firewall. The Piper installed electric pump is removed and replaced with a pair of redundant electric fuel pumps. You may run one pump or the other but when properly wired it is impossible to run both pumps at the same time. The FMS calls for one of the pumps to be activated for taxi, takeoff, climb, landing, and again for taxi. You may run them in cruise if you wish but it's not necessary to do so. The fuel system plumbing forward of the firewall consists of steel and stainless steel tubing and fittings. The tubing is bent to shape in our shop and comes to you attached to the pumps as an assembly ready to be tightened up and mounted on the firewall when you receive it.
Click to expand...

That is completely wrong for most PA-28s. I think that's just for fuel injected PA28-181s, but I'm not sure.

Our PA28-151 and PA28-235 required nothing but paperwork.

Of course, the STC itself is now completely worthless, thanks to the mandate to pollute all car gas. :mad2:
 
tonycondon said:
yes seriously. Iowa is one of the few states that requires ethanol blended gasoline to be clearly labled. and they do not make ethanol blend mandatory. a good policy, IMO
Click to expand...

Yep, we were still burning mogas in our plane when we lived in Iowa -- the land of ethanol production.

Now, 16 months later, in the land of oil production, unpolluted mogas is impossible to find. After nearly 13,000 gallons, I have sold my tanker truck and gone back to burning that evil 100LL.

Our O-540 runs like crap on 100LL. It was designed for 80, and runs much better and cleaner on 87 octane mogas. I still can't believe the morons in D.C. mandated that ALL gas be polluted with that corn crap.
 
Tom-D said:
You must know that the vapor pressure of alcohol is much lower than standard fuel stock.

They know it too, that is why they won't try to certify it.
Click to expand...

Such nonsense. The Vanguard Squadron has been running their Lycoming O-320s on PURE ethanol (and other assorted blends) for SIXTEEN YEARS.

Read about them here: http://www.vansairforce.com/community/showthread.php?t=58334

The only reason no one can certify ethanol blends is the government obstructionists. Yes, it makes less power -- so what? My engine makes less power when it's hot -- should the government outlaw flying on hot days?
 
I was looking over Jim's list of airports that sell unleaded fuel (see post #7 above), and found it ironic that one of them that sells the non-ethonal fuel is Denio Junction, Nevada. Its identifier is E85 :) :) :)
 
alaskaflyer said:
That's good. Because they haven't.
Click to expand...

In the Lower 48 they sure have. Sure, there are a few "fringe" stations remaining who sell unpolluted gas in small lots, but they are owned by folks like us who need unpolluted gas -- primarily racers, down here. Unfortunately, the nearest one to me is a 40 minute drive, so I'm back to the blue crap.

Edit: Here's a better explanation: http://answers.yahoo.com/question/index?qid=20100312143430AAXd2qK

Once again, we have experienced legislation by bureaucratic mandate, rather than through any democratic process we can influence.
 
Last edited:
alaskaflyer said:
That's good. Because they haven't.
Click to expand...

Violation of a mandate is met by punishment. Conformance to a mandate is met with reward or no punishment. The reality of EISA 2007 is that it appears to be semantically close to being a mandate that the difference is not worth arguing over. There is this view: http://e0pc.com/newreality.php
 
Last edited:
Tom-D said:
You must know that the vapor pressure of alcohol is much lower than standard fuel stock.

They know it too, that is why they won't try to certify it.
Click to expand...
True- Vapor pressure of ethanol = 5.95 kPa (at 20 °C), BP avgas=43.4 kPa (ref= http://www.bp.com/liveassets/bp_int...s_pdfs/a/air_bp_products_handbook_04004_1.pdf)

Jay Honeck said:
Such nonsense. The Vanguard Squadron has been running their Lycoming O-320s on PURE ethanol (and other assorted blends) for SIXTEEN YEARS.

Read about them here: http://www.vansairforce.com/community/showthread.php?t=58334

The only reason no one can certify ethanol blends is the government obstructionists. Yes, it makes less power -- so what? My engine makes less power when it's hot -- should the government outlaw flying on hot days?
Click to expand...
Ethanol also promotes corrosion of aluminum and damages fiberglass fuel tanks (http://www.nmma.org/assets/cabinets/Cabinet103/E20_Position_Paper.doc). It also tends to attract water that falls out of solution when it gets cold.
 
Tom-D said:
OBTW,,,,,,, it's the new MA-3 carbs that have the rubber tipped needle valves, the old ones have a brass needle and stainless seat.

Now Kelly aerospace is using plastic floats needle valves, and a 1 piece venturi..

that's why you never have your old carb rebuilt by them or buy a new Precision or Kelly carb.
Click to expand...

I have two Stromberg carbs here, both with rubber-tipped needles. They're not MA-series carbs. They're the NAS-3 carb.

Dan
 
Jay Honeck said:
Such nonsense. The Vanguard Squadron has been running their Lycoming O-320s on PURE ethanol (and other assorted blends) for SIXTEEN YEARS.

Read about them here: http://www.vansairforce.com/community/showthread.php?t=58334

The only reason no one can certify ethanol blends is the government obstructionists. Yes, it makes less power -- so what? My engine makes less power when it's hot -- should the government outlaw flying on hot days?
Click to expand...

Yep and every one of the VANs thingies have a fuel pump.

Try getting it to work 100% of the time in a gravity flow systems such as a C-high wing.

And remember the narrower the market the less chance of getting it certified.
 
You must log in or register to reply here.
Back
Top