Ok after doing a mountain of research on this subject I can find no concrete proof that running mogas in a low compression engine that has been approved causes any damage what-so-ever. I have contacted the EAA (who by the way have some of the brightest people going in aviation) Todd Peterson of Peterson Aviation, I have read articles by Ben Visser of Shell Oil Company, gotten emails from people from the Piper Owners Society who have over 2900 hours on O320’s running mogas yet mechanics still claim it’s like signing the death warrant for the engine. I hear mechanics bad mouthing mogas all the time yet they have nothing specific to back up their claims, nor do they really have any experience with it. Every thing is always hear-say! “Well I know a engine guy who says he’s done a couple of engines running mogas”, yeah well ask him how many he’s done that have been running nothing but 100LL! If organizations such as the EAA and Peterson have done extensive testing with very positive results why are mechanics so afraid of it?
To quote Ben Visser from Shell …
“The American Society for Testing and Materials (ASTM) is the controlling agency for both the auto gas and avgas specifications. The ASTM D- 910 specification for aviation gasoline lists about 30 different limits or tests, which must be met prior to releasing each and every batch. Most blends of auto gas would meet many of these specifications, or the difference is totally insignificant. For example, avgas is dyed blue while auto gas is normally clear. So other than for identification purposes, there will be no difference in performance.”
Another quote from a posting from the Piper Owners website...
"Precious owner, an Instrument Training school used my Apache for about 3,000 hours with STC for mogas, about 8 years at I guess about 16 gals per hour, or about 48,000 gals with a savings of about $19,000 After careful inspection of engine logs I found NO REMARKABLE difference in maintenance of the 150hp O 320 engines using mogas over my usage of avgas on 3 Cherokees and a twin Comanche. Other than savings only other noted difference was NO PLUG FOULING in summer time using mogas. Engines went well over TBO and on overhaul it appeared crank and cam had less wear."
Can someone from the AME side provide me with hard data to say mogas is the cause of any engine damage specifically? I lost a ring in my cylinder due to lead build up from running 100LL even though I leaned it as per Lycomings instructions and change the oil and filter every 25 hours. So 100 LL is causing as much if not more damage to engines from what I have read and experienced.
Waiting for the technical data to back up claims about mogas being bad!
Of course only use of it in aircraft that have been properly tested and STC'd for using it and that all precautions spelled out in that STC are strictly adhered to.
Avgas vers Mogas
Moderators: sky's the limit, sepia, Sulako, North Shore
Avgas vers Mogas
Putting money into aviation is like wiping before you poop....it just don't make sense!
N2 I think you answered your own question. Have seen some mogas problems. STC not installed, owner/operator didn't have a clue...Of course only use of it in aircraft that have been properly tested and STC'd for using it and that all precautions spelled out in that STC are strictly adhered to.
If used on the right engines with proper operation fill yer boots...
My 2 cents...
Yoyoma here are a couple for ya, just doing a search on google will throw up a ton of sites!
http://www.fly-low.com/features02/autogas.html
http://www.eaa.org/education/fuel/savings.html
http://autofuelstc.com/autofuelstc/pa/P ... ation.html
http://www.avweb.com/news/maint/187232-1.html
http://www.fly-low.com/features02/autogas.html
http://www.eaa.org/education/fuel/savings.html
http://autofuelstc.com/autofuelstc/pa/P ... ation.html
http://www.avweb.com/news/maint/187232-1.html
Putting money into aviation is like wiping before you poop....it just don't make sense!
Thanks for links! Some good info in there...Could you tell me though what they mean by:
In order to qualify for an STC, a particular airframe/engine combination has to be rigorously tested, to include either a 150 hour engine endurance test or 500 hour flight test, under controlled conditions.
What are controlled conditions?
Cheers
In order to qualify for an STC, a particular airframe/engine combination has to be rigorously tested, to include either a 150 hour engine endurance test or 500 hour flight test, under controlled conditions.
What are controlled conditions?
Cheers
Well when I talked with the EAA guys last summer in Oshkosh they indicated to me that all the testing was surpervised by FAA officials. You could email them for clarification as to what exact conditions were.
Putting money into aviation is like wiping before you poop....it just don't make sense!
This is the answer I got from a nice guy at EAA:
This testing was done by us here at EAA,
in order to gain the STC's from the FAA in the first
place. The controlled conditions were related to
temperatures, both atmospherically and operationally.
We did extensive testing to prove to the FAA that auto
fuel would be suitable in the engines and airframes
that we wished to have listed as eligible for the STC.
A person who purchases the STC is simply required to
have an authorized mechanic inspect the aircraft and
take care of the paperwork. There are a small number
of cases where the aircraft may need certain
modifications in order to be eligible for the STC, but
this is rare. In most cases, there is only an
inspection and some paperwork to take care of.
Hope this helps!
Cheers
This testing was done by us here at EAA,
in order to gain the STC's from the FAA in the first
place. The controlled conditions were related to
temperatures, both atmospherically and operationally.
We did extensive testing to prove to the FAA that auto
fuel would be suitable in the engines and airframes
that we wished to have listed as eligible for the STC.
A person who purchases the STC is simply required to
have an authorized mechanic inspect the aircraft and
take care of the paperwork. There are a small number
of cases where the aircraft may need certain
modifications in order to be eligible for the STC, but
this is rare. In most cases, there is only an
inspection and some paperwork to take care of.
Hope this helps!
Cheers
In the business world, the rearview mirror is always clearer than the windshield...W. Buffett
Hot soaks can be a problem but only at extreme temps so I have been told by companies who have done a lot of research. Normally when the temps are high any fuel is prone to vapour lock. I had it one day on a C310, I was taxing out and the left engine just quit. It was running 100LL so it just shows it can happen to any fuel if a hot soak is allowed to happen. Dr. Hodge from Australia makes a gauge to test the fuel for it's likelihood of vapour locking. I test my fuel before each flight and have never had a bad reading yet.
To avoid encountering vapour lock after a hot soak a good run up is really all you need to do. That is something I would do from now on in any aircraft because I know even running 100LL that vapour lock on a hot day is possible in that machine.
To avoid encountering vapour lock after a hot soak a good run up is really all you need to do. That is something I would do from now on in any aircraft because I know even running 100LL that vapour lock on a hot day is possible in that machine.
Putting money into aviation is like wiping before you poop....it just don't make sense!
I started work in Australia and was there for 9yrs before coming here and I worked on many C172/180/182 running mogas. Many farmers run it as its all they can get easy. The only differance was a placard saying to drain the tanks often. this was mainly due to the fuel from drums issue. There was no abnormal effects that were known. I think that the wives tales of burning valves etc is just that. Same as putting avgas in your car. The only damage is if you have a Catalyitic converter, othervise nothing. Many ame's fun it as its free to get , its always laying aroung the hangar.
As for an STC it wasnt an issue in OZ but i havent worked on similar types here so dont know, but as for wear and dammage No!
As for an STC it wasnt an issue in OZ but i havent worked on similar types here so dont know, but as for wear and dammage No!
