The International Cessna^® 170 Association

Well, unless something is specifically "prohibited" by the manufacturer, then it really is only a "recommendation", a "suggestion" if you will, and should be treated as such.

Having said that, I guess we need to define what "restriction" really means and it's implication. My gut feeling is it's more likely we could substitute "recommendation" or "suggestion" for "restriction" in this case.

The real problem I see with the ethanol laced fuel is the percentage. I've checked many of the local stations and found very few with what is advertised on the pump.
One station (independent & a bulk dealer) that advertises "0" Ethanol had a 10% content at his own signature station. Yet when testing other stations he supplies I found from 5% to "0"%. He and I had a talk and concluded he is at the mercy of the refinery that supplies him. I say check what you use and be aware of what % really enters your airplane
Have there been any real studies on the "Carb ice" issues and ethanol laced fuel?
BTY: I found one cut rate station selling 35% ethanol in their fuel. Had "up to 15%" sticker on pump. Guess that is why they sell cheaper than others.

I have a cousin that works in small engines and since ethanol has been introduces into gas, he loves the combination. He told me that he has more business rebuilding and replacing fuel system componets than ever before and makes very much money from this combination. I use avgas only since about 2003 due to I don't need to introduce any problems for future repairs.

John

I have noticed that almost all cousins work on small engines that are screwed up by the use of alcohol laced fuel. Thats why you NEVER see any home owners out mowing their lawn with a gas powered mower, especially here in California where you just can't find any straight gasoline any more. The same thing holds true for ATVs, Motor Scooters, Light Motorcycles, Leaf blowers, etc., etc., etc.
All old automobiles like my '63 Ford Galaxy Convertible (I bought it new in '63) are going to die soon because of it. The last twenty five years or so on the stuff has been hard on the old Ford, I think. My youngest daughter drives it now and says it runs fine, but shes a woman and what the hell does she know about that kind of stuff?
Anyone qualified to work on a Briggs and Straton engine on a lawn mower is bound to be an expert on this sort of thing.

WSHIII wrote:...Chevron reports their fuel is stable for two years, .....

Not doubting you..but exactly when/where did they make that claim? How is it to be stored to meet that claim. Can you provide a reference?

I have some absolutely scientifically provable evidence that mogas cannot be relied upon in airplanes.
Ask Gary Hanson (Ol'Gar) how long it took for us to get his C150 airborne after he used mogas in it. (And HE is ...or was...a mogas proponent.) I thought I'd never get all the crud out of that system.
Ask about his 170 carburetor while you're at it. And about the 150 carb we had to clean up again after annual.

Mogas is simply rotten for airplanes ...or any other engine...unless it's used fairly promptly. It has not much shelf-life once it's been delivered into a vehicle.

If it's fresh...if it's used promptly...if it's clean...then it probably will not kill you or your airplane right away.
But unless you use every bit of it up ....if you let it sit for more than a few weeks.... then you're asking for trouble, and there's no "scientific data" needed to make the point. It's no more necessary than the same anecdotal proof mogas users have.

In any case, when mogas costs $3.75 here in TX, and avgas costs only $4.50 locally.... (and Kelly Aerospace gets $350 for a carb overhaul kit and $1870 for an exchange/overhaul)..... there's damn little argument that's going to convince me to put mogas in my airplane that only operates 50 hrs/year and will sit in the hangar for weeks between flights before it carries my wife and grandkids at night.

gahorn wrote:In any case, when mogas costs $3.75 here in TX, and avgas costs only $4.50 locally....

MOGAS with ethanol today $3.67 MOGAS without ethanol available with limited hours at one station most of the time 66 miles round trip away for $3.95. AVGAS at my airport today $6.23.

You can see why folks who don't live in Texas consider MOGAS. Heck if I lived in Texas I'd run 100LL in my lawn mower (which my buddy does even at $6.23 to keep it running without the ill effects of MOGAS with ethanol)

Bruce Fenstermacher wrote:[... Heck if I lived in Texas I'd run 100LL in my lawn mower (which my buddy does even at $6.23 to keep it running without the ill effects of MOGAS with ethanol)

Well....THAT is an example of the best endorsement of avgas. It's simply better quality stuff, and that has nothing to do with where one lives.

How many of us know someone (if not ourselves) who refuse to put cheap motor oil in their engines...instead, putting some higher-priced, name-branded stuff in them?
How many of us know someone (if not ourselves) who spend extra money on additives and snake oils, because it makes them feel better about the quality of their fuels/lubricants?

Doesn't it make just as much if not more,... sense, to put the highest quality gasoline available in our expensive and high-risk-for-reliabilty aircraft engines?

The shelf-life of mogas is measured in weeks....and even then, the stuff is low quality, of questionable cleanliness, and dubious concoction. (Avgas is many months, and plenty of examples of years of storage without a problem.) I've lost carburetors (no longer repairable) in my portable generators, my garden tiller, my stern-drive boat, and almost lost the one in my pressure-washer....all due to the use of mogas. Tired of losing expensive equipment, I too, only use avgas for the last seasonal-use and long-term storage of such engines. It's saved me lots of downtime, troubles, and expense, .....and that is the kind of "proof" and "documentation" which works for me.

WSHIII, ...have you ever read the Type Certificate Data Sheet for this airplane? Check out the FIRST prohibition issued, on page ONE, about "alcohol based fuels".
Then check out the exact fuel specified a few lines later. (Hint: It's not "automobile" gasoline.) Seems pretty clear to me.

Good Morning George!!!

Good to see up up and about.

Hope you have a good day


W.

I doubt I can find the reference again now, I came across it several years ago when I was in another one of these discussions. It appeared to be from in the '90, pre-ethanol. So I'll grant you it is now somewhat dated and you can assume whatever you want from that. Again, I leave planes sit for several months at a time without any problems. And the only time the carburetor or any of its parts get changed is at overhaul. Ever!

I thought I said so right at the beginning but maybe I wasn't clear enough. I do NOT advocate using Mogas with Ethanol. Period! I have no experience with it, zero. So, I'm not sure what your reference to the TCDS is supposed to infer with regard to Ethanol based fuels.

As for the "Octane and Aviation fuel" being specified in the TCDS. I don't see my engine or any other applicable STC listed on there either. So, unless your aircraft is exactly how it was certified and came from the factory, in strict accordance with the TCDS, it's somehow unairworthy, not approved, illegal. Is that going to be your position?

$.75 x 7 gph x 2,000 hrs = $ 10,500

Or in my case with an 0360 and overhauling "on condition" and hopefully making it at least 3,000 hrs.

$.75 x 9 gph x 3000+ hrs = $ 20,250

George

Actually I glad you came aboard on this subject, I have been to your place and I think I know you a little bit anyway and your knowledge base is quite broad, but I like to 'Trust but Verify" the older I get. There are many people out there that make comments that only repeat what they have heard and not what they have seen.
I know you have had grease under those fingernails so I always like what you have to say, and I'm sort of a direct personality type of guy so I appreciate your directness.

Back when I had '54B" with the o-300, I could get 92 with no E and yes I tested it on every batch. South Dakota was one of the last states to sell gas with any E in it. Don't know if gas is still available without E in it in S.D. or not because the i0 520 drinks different stuff. I had a 100 gal tank in the back of my pickup truck and at the time there was a $2/gal difference. I'd run 75(92) and 25 (100ll) and never seemed to have any issues......maybe I used up my nine lives eh.
Maybe if you have time you could round up some pictures of some damage done by using 92 oct with no E in it and put in in the 170 news. Would like to see some actual data.

Like always thanks for all that you do George, would like to hang around your hanger more so I can learn some more


W.

?.......... and there's no "scientific data" needed to make the point. It's no more necessary than the same anecdotal proof mogas users have.

Well, you seem to be discounting the fact that the FAA has looked at the real "scientific data" and has agreed that using Ethanol free Mogas is safe.

You (collectively) OTOH, say it's dangerous but offer only anecdotal evidence as proof.

You really don't see the difference?

George,
If I had as much trouble with mogas as you have had, I'm damned if I'd even put it in my car.

WSHIII wrote:

?.......... and there's no "scientific data" needed to make the point. It's no more necessary than the same anecdotal proof mogas users have.

Well, you seem to be discounting the fact that the FAA has looked at the real "scientific data" and has agreed that using Ethanol free Mogas is safe.

You (collectively) OTOH, say it's dangerous but offer only anecdotal evidence as proof.

You really don't see the difference?

Collectively? ? Huh?

It's not "anecdotal" if it's personal experience (as opposed to hearsay.)

And I'm not discounting the FAA having looked at the data... but I was discussing the ethanol-laced stuff...perhaps I wasn't clear on that matter.
The problem I have with non-ethanol mogas is the lack of quality controls regarding recipie, delivery and storage...and shelf life. Like I've said in the message you excerpted (a bit out of context).... the use of non-ethanol gas is probably OK....IF it's clean and used completely, quickly, and not stored. But it's still not a well-regulated recipie, it still has storage/delivery problems (at most anywhere except perhaps at airports), and it still has a certain degree of risk if used at high altitude (admittedly, not much of a problem with normally aspirated engines.)

It's your airplane. It's your money. It's your liability. It's your choice.

"Collectively" in this case, meaning those as a group who oppose the use of Mogas.

" it's not anecdotal if its personal experience ( as opposed to hearsay)"

Actually, it can be.

Anecdotal: 2) "based on or consisting of reports or observations of usually unscientific observers <anecdotal evidence".

And therein lies a big part of this problem. Many think that just because they have direct knowledge or first hand experience of a problem, that they themselves have already decided is from using Mogas. That that experience or first hand knowledge, somehow rises to the same level as the evidence, data, collected by an unbiased controlled scientific study. Unfortunately it doesn't, nor should it.

Inevitably, this is almost always where these discussion end up. Arguing semantics, context, parsing of words..........
Neither side budging, nor convincing the other of the righteousness of their position. No surprise there I guess and why there are Democrats and Republicans. Predictably, sadly, with often the same outcome.

I read Georges last post and this is what I got from it-
the use of non-ethanol gas is probably OK