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UngaWunga

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UngaWunga
I think we can all agree that lead in the environment is a bad thing. After hearing a new story about how researchers found that many raptors and scavengers have toxic levels of lead poisoning due to consuming lead fragments while feeding on gut piles during hunting season, and thinking about all the times avgas gets dumped on the ground at my local airport, I figured why not stop adding to the problem. Yes, the lead in fuel in very small, but its still there. My local airport sells mogas. Alcohol free, cheaper than avgas as well. Peterson sells the STC for the paperwork so I can legally use it in my 172 with the O-320.

Are there any reasons why I shouldn't do this? I'll recoup the cost of the STC within a few tanks. The airport sells quality mogas sans alcohol. Gravity fed fuel system in the 172, so the chance of vapor problems is very small. The engine has cylinders made within the last 20-30 years, so the valves should need it. I don't see the downsides to this.
 
Your engine oil will thank you.

I’ve been quietly educating fellow pilots about dumping sumped avgas on the ground for a few years now. It’s just a habit that we don’t need to be doing. The ‘educating’ part is tough because the topic doesn’t come up very often outside of the training environment. I try to come up with a humorous, non-confrontational way to mention dumping and fortunately have the folks in Boulder to pick on. That was fine until I had a flight review in Boulder.

Anyway, fuel is to be consumed in an engine. It doesn’t belong on the ground.
 
I've been running Mogas in my O-470 for the past 2 months. No issues for me. Well, my gascolator has started leaking, but thats more a symptom of the plane not being flown the 2 years before I bought it than the mogas.
 
Clark1961 said:
I’ve been quietly educating fellow pilots about dumping sumped avgas on the ground for a few years now.
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I have a low wing, sumpted gas goes right back into the tank.
 
I’ll admit, I’m guilty of several years of pouring sumped fuel on the ground. I used to sump it, and pour it on weeds that managed to grow through cracks in the tarmac. Within the past few months, I’ve come to the realization of questioning why I do that, as it’s ultimately wasting perfectly good 100LL.

Guess it’s one of those bad habits that rubbed off on me early on by a CFI.
 
Clark1961 said:
Your engine oil will thank you.

I’ve been quietly educating fellow pilots about dumping sumped avgas on the ground for a few years now. It’s just a habit that we don’t need to be doing. The ‘educating’ part is tough because the topic doesn’t come up very often outside of the training environment. I try to come up with a humorous, non-confrontational way to mention dumping and fortunately have the folks in Boulder to pick on. That was fine until I had a flight review in Boulder.

Anyway, fuel is to be consumed in an engine. It doesn’t belong on the ground.
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Exactly. I put the fuel that I check from the tank sumps back into the tanks if they look clear, but the gascolator drain I can't catch. So onto the ground if goes. There's very few pilots that I've seen that catch the fuel and put it back into the tanks. Most just fling it "away"... Lead doesn't go away.
 
UngaWunga said:
Exactly. I put the fuel that I check from the tank sumps back into the tanks if they look clear, but the gascolator drain I can't catch. So onto the ground if goes. There's very few pilots that I've seen that catch the fuel and put it back into the tanks. Most just fling it "away"... Lead doesn't go away.
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Lead doesn’t go away and hydrocarbons are extremely slow to oxidize outside of an engine or fire.
 
Mtns2Skies said:
So you're saying it's okay to dump the fuel on the ground as long as we light it on fire after? :D
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I’ve often suspected CSU grads had a tough time with reading skills. Must be the air in that region has a negative impact on certain cognitive functions.
 
Mtns2Skies said:
So you're saying it's okay to dump the fuel on the ground as long as we light it on fire after? :D
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Clark1961 said:
I’ve often suspected CSU grads had a tough time with reading skills. Must be the air in that region has a negative impact on certain cognitive functions.
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9814274.jpg
 
Often if you fly a high wing and the only sump tool available is the long narrow tube type rather than a gats jar, you almost have no choice but to dump it on the ground. I personally can’t get up on the wing while holding the tube so that it won’t spill. With the gats jar, I can sit it on the cowling while I hoist my fat ass up there. My club has the tube type in both planes and though I suggested buying gats jars, they have yet to do so. Maybe I’ll be charitable and just pay for a couple out of my own pocket and hope they get used properly.
 
When I started taking lessons, I was told to just toss the fuel samples. Never did like that. I bought a GATS jar, and from that day on every sample went back into the tank -- cleaned and filtered. It works with either type of drain.
 
Bill Jennings said:
The pin goes up into ours, so that fuel goes back into the tank as well. (Provided it's clean of course)
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Some Cessnas have the gascolator drain hidden under the cowl. All you can do is look at the fuel after it has splattered on the inside the cowl and drained out of the bottom. Really inconvenient to catch that sample and ya never know the source of contamination.
 
SkyDog58 said:
My club has the tube type in both planes and though I suggested buying gats jars, they have yet to do so. Maybe I’ll be charitable and just pay for a couple out of my own pocket and hope they get used properly.
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I just bought my own and put it in my flight bag.
 
To the OP- in your situation, I would definitely be burning mogas. An A&P/IA friend of mine with a O-540 powered Bearhawk has been running a mix of 80% mogas/ 20% 100LL for a couple of years, and really likes it. Unfortunately, I have an 0-320/160hp in a low wing aircraft with no mogas on the airport and all of the mogas available nearby is an E10 mix.
 
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SkyDog58 said:
My club has the tube type in both planes and though I suggested buying gats jars, they have yet to do so. Maybe I’ll be charitable and just pay for a couple out of my own pocket and hope they get used properly.
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Lead is nasty stuff and does accumulate over time. It would be awesome for you to do that! Every little bit helps.
 
edo2000 said:
In your situation, I would definitely be burning mogas. An A&P/IA friend of mine with a O-540 powered Bearhawk has been running a mix of 80% mogas/ 20% 100LL for a couple of years, and really likes it. Unfortunately, I have an 0-320/160hp in a low wing aircraft with no mogas on the airport and all of the gas available nearby is an E10 mix.
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Gas stations that cater to the boating crowd often have ethanol free gas. Marinas as well.
 
what do u do if u sump and there's water in it and also no dumping bucket?
 
Mogas is not guaranteed to be as consistent or have the same additives as 100LL. 100LL content consistency and quality is more closely controlled. Mogas may work ok in your plane, it depends. Some airport operators actually have a tank on a trailer and go get mogas from a car filling station. I've even seen some that say their mogas is 91 octane, yet the supplier is selling the same mogas to a car gas station and the car gas station is saying its 87 octane. Im not saying dont use it but quality is the downside.
 
eman1200 said:
what do u do if u sump and there's water in it and also no dumping bucket?
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You replace the gaskets on the fuel caps or tighten the gas caps better on a Mooney. Then email the fuel sample to @SixPapaCharlie since he drinks the stuff for breakfast.
 
Clark1961 said:
You replace the gaskets on the fuel caps or tighten the gas caps better on a Mooney. Then email the fuel sample to @SixPapaCharlie since he drinks the stuff for breakfast.
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Gas cap gaskets get replaced every year at annual. Water in gas bad.
 
DaleB said:
I just bought my own and put it in my flight bag.
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I’m already carrying too much junk in mine. That’s why if I do decide to buy, I’ll buy two and donate them to the club. That also helps others to not dump on the ramp.
 
Unless there is a reason not to, I'd consider adding fuel stabilizer to the MoGas. Mogas has a lot of alkenes which seem to polymerize over time. The alternative is to fly a lot so the fuel is "turned over" often and doesn't sit.
 
Random Data points:

  • EAA is likely to also have the MoGas STC for you airframe/engine combination. Last time I checked Peterson and EAA were the same price. But there are a few advantages with buying from EAA. First, you're supporting an organization that supports GA in general. Second (as I found out first hand because I bought an airplane that had a Peterson STC and it had never been submitted and the paperwork was MIA) if you ever need to have the paperwork re-issued for whatever reason, The EAA charges a nominal fee to cover their costs. Peterson charges 50% the original cost. At least this was the case when I had to have mine re-issued.
  • I try to keep somewhere between a 2/1 and 3/1 MoGas/100LL blend in my plane (O470L). I think a little lead is good and my engine was designed to burn 80 octane which had about 1/4 the amount of lead in it as 100LL does, so the blend gets the lead and octane content down closer to what the engine (and spark plugs) like.
  • I don't know where you live but you might check out other potential sources for 0E in your area. This website is a very good resource and it's kept reasonably up to date: www.pure-gas.org
  • I schlep 5 gallon cans of MoGas to the airport if I'm domiciled at a field that doesn't have it. I don't find it to be a hassle at all. Others despise it. To each his/her own.
  • 80 octane aviation fuel is roughly equivalent to the old 87 octane leaded auto gas. The octane scale is just different. Thus the 91/93 octane MoGas that's available here in MO is NOT 91/93 on the aviation scale. It's more like 85 octane.
  • Sumping: If it's clean it goes back into the tanks. If it's not it goes into a small lawnmower engine (or sumsuch) if I'm at my hangar, or HOPEFULLY, a disposal jar at the gas pumps if I'm on the road. Not all airports provide disposal jars at their pumps but it should be required.
  • I truly believe that if it was a problem running MoGas in Airplanes then the FAA wouldn't allow it being the over-regulators that they are. My last engine run went over 1,500 hours burning MoGas at the above reference ratios. Assuming it consumed only 50% MoGas (which is definitely on the low end) during that run, at an average of $1/gal difference (and sometimes it was far more), the savings was roughly $10,000. That was a good down payment on the recent overhaul.
  • I have no idea what Colorado Blue Sky was trying to say (especially in his second last sentence). I'm not even sure there was English in there! ;)
 
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coloradobluesky said:
Mogas is not guaranteed to be as consistent or have the same additives as 100LL. 100LL content consistency and quality is more closely controlled. Mogas may work ok in your plane, it depends. Some airport operators actually have a tank on a trailer and go get mogas from a car filling station. I've even seen some that say their mogas is 91 octane, yet the supplier is selling the same mogas to a car gas station and the car gas station is saying its 87 octane. Im not saying dont use it but quality is the downside.
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Airfield has a separate in ground tank for mogas. I've never had any contaminants in my fuel from the airfield, and I check every time after getting fuel. They get 91octane from the local distributor, not from a local gas station.
 
I had a 172 that I burned Mogas in. Was cheap flying. Have a 172m I’m planning on getting Mogas stc for in next few months. As far as sumping gos, several years ago my wife asked the fbo where the tank was to put sumped gas in on the ramp. They told her to just throw it on the tarmac. She said she was a epa inspector. They had a sump barrel the next day
 
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eman1200 said:
what do u do if u sump and there's water in it and also no dumping bucket?
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That's why I have the GATS. It will put the gas in the tank and leave the water in the jar.

Cap'n Jack said:
Unless there is a reason not to, I'd consider adding fuel stabilizer to the MoGas. Mogas has a lot of alkenes which seem to polymerize over time. The alternative is to fly a lot so the fuel is "turned over" often and doesn't sit.
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In an Experimental, you can do whatever you want -- I prefer to fly often enough to not let the gas sit for extended periods. I don't think we've ever had gas get more than a couple of months old; it's usually a couple of weeks. It helps to have 2 people flying. In a type certificated airplane, would adding a fuel stabilizer even be legal?

Nothing but MOGAS here for 2-1/2 years now, other than an occasional top-off with AVGAS when nothing else is available. There were a couple of tanks of Swift fuel in there as well. Zero issues. Of course it's a Rotax, so the metric fairy dust helps to ward off evil spirits.
 
Back when I had a gas burning, non computerized, non electronic fuel injected carbureted truck, I put the waste 100LL in the tank.
 
SkyDog58 said:
I’m already carrying too much junk in mine. That’s why if I do decide to buy, I’ll buy two and donate them to the club. That also helps others to not dump on the ramp.
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Not sure why you are complaining here about your junk. Do not post pictures of your junk. See a urologist if your junk continues to bother you.
 
I burn mogas because it is nearly half the cost of 100ll. It’s worth it to haul around the 5 gal jugs. I have a high wing so dumping the fuel back into the tank is a pain. I just dump it in one of the 5 gal jugs. Easy peasy.
 
Consider verifying if the FBO is actually delivering E0. We had an incident in our area about 10 years ago where an FBO was supposedly receiving certified E0 for aviation use but in reality his fuel system was receiving mostly E10. It swelled the fuel line almost shut in my hangarmate's C-140. In testing it turned out to ~E5. The FBO tried to get info on previous aircraft he had refueled from the credit card companies but they refused to divulge the owners names and addresses. That was 10 years ago though.

We ran gas station E0 in our 172M for ~1000 hrs, but we checked it for alcohol. Sure kept the oil and plugs clean...
 
Ken Ibold said:
Gas stations that cater to the boating crowd often have ethanol free gas. Marinas as well.
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Yeah, we do have a lakeside marina that carries "real" gasoline, but it is 30+ miles away. My real issue is my higher compression 0-320 and a low-wing airplane. Mogas not recommended as far as I can tell.
 
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