What fuel do you burn?

[eaglevets]

I get lots of different answers when I ask what fuel I should be running - regular, high test, ethanol-free, avgas, with or without additives, etc. I get dizzy considering all the options. What to you burn in your MUTT and why? Thanks!!

[m3a1]

I burn regular unleaded with off-the-shelf lead additive in my 1970 pre-emissions A2.

[rickf]

Regular unleaded. But then again, I do not drive mine long distance and I also do not put a lot pf miles on it. If you have a late model head then you already have the hardened valve seats and you are fine with unleaded gas. If you have an earlier one and you drive a lot of miles, I am talking a thousand miles a month, then a lead additive is a good idea. IF you can get non alcohol gas that is great. it cannot be found in NJ. We are also not legally allowed to buy gas in cans from an airport since there is no road tax paid on avgas. And believe me NJ is all about taxes!! There was one small airport that we could drive right up to the pump and fill up but someone reported them and they were heavily fined, end of that luxury.

[agwrangler]

If you can get AVGAS, use it. My MUTT runs best with it, and so do my other MV's. You can actually tell a difference in performance. I will never use anything else in my MV's.

[Hambone]

If you can get AVGAS, use it. My MUTT runs best with it, and so do my other MV's. You can actually tell a difference in performance. I will never use anything else in my MV's.

Ditto on avgas, even if you let it set a year, you are still good to go.

[Horst]

Avgas is high octane leaded gas. I have no idea how a low compression engine should run better with it, but honestly I never tried. But thinking about it, we are draining on every flight some amount of fuel out of our Robinson, I should start putting that into my 151.

Without any doubt Avgas will have a much better shelf life than Mogas. However, my jeeps sits for at least 6 months over the winter and I never have issues starting and running it when the summer comes back. I pour Seafoam into the tanks of my GTO and the Zook, but I guess it just makes the manufacturer happy and gives me a warm and fuzzy feeling, not sure if it actually does any good.

[Husker]

I don’t think I can run my mutt on Blackhawk fuel

[Hambone]

Avgas is high octane leaded gas. I have no idea how a low compression engine should run better with it, but honestly I never tried. But thinking about it, we are draining on every flight some amount of fuel out of our Robinson, I should start putting that into my 151.

Without any doubt Avgas will have a much better shelf life than Mogas. However, my jeeps sits for at least 6 months over the winter and I never have issues starting and running it when the summer comes back. I pour Seafoam into the tanks of my GTO and the Zook, but I guess it just makes the manufacturer happy and gives me a warm and fuzzy feeling, not sure if it actually does any good.

My son works at the local airport, they pull 2 gallons a day off the fuel truck, , my 2 strokes like it also.

[Horst]

I don’t think I can run my mutt on Blackhawk fuel

as it doesn't run on Avgas this shouldn't be a surprise...However you can put diesel in your Blackhawk and it will not notice the difference

In that context, what I found interesting that the M35 multi-fuel diesel is not approved for Avgas but pretty much everything else.

[rickf]

Avgas in this country is all 100LL, Which is very close to unleaded. The big advantage to Avgas is that it does not have all of the additives for emissions that they put in automotive gas. Especially no alcohol. This is why Avgas will sit for long periods without going bad. It is the additives that break down for the most part. If Raymond see's this I am sure he can enlighten us in fine detail. As far as the higher octane, the higher the octane the less power you will get from the gas in a low compression engine. The higher octane gas is designed not to detonate as easily therefor it does not have as much volatility as lower grades of gas. The difference is so little that you will actually feel no difference at all but what microscopic difference there is is in the opposite direction than you would think.

[Horst]

but don't get confused by the "LL", standing for low lead... There is a lot of lead in Avgas, there are quite a few people trying to ban it. A lot of testing was already done removing the lead and no harm was found on all the aircraft engines they tested but it probably will still be around as long as gas burning aircraft engines will be around. Not sure if the high lead content is the reason a deuce engine should not drink it.

[Mark]

I can't find anyone who has it or will sell it to, the Avgas that is

[raymond]

Aviation gasoline has more, not less additives. Airplanes often sit for months on the tarmac without use. That is why it has a longer shelf life. Not sure about other brands, but Shell's V Power Premium has multiples of detergent additives over their Regular. While that won't give you any performance enhancements, that should improve it's shelf life. And one last thing, store you vehicle with as full a tank as you can get. Oxygen is the enemy of all fuels. As fuel changes temperatures, in addition to the changes in density to barometric pressure, it also increases and decreases it's Reid Vapor Pressure. That means more air goes in and out of the tank. That increases the amount of oxygen and moisture that can come in contact with the fuel. That increases the chances for the gasoline to be affected.

Raymond

[rickf]

Raymond, Just how much lead is there still in aviation gas? I have heard from "a lot" to "None". I know gasoline from back in the 60's-70's would sit for more than a year and still run with no problems. I had been told that this was because there were a lot less additives for emissions in the gas back then, It was just gasoline. I know when I had my station the gas smelled totally different then it does now. And as far as sitting, gas with alcohol in it will go into phase separation at 6-7% water volume and it does not take much to achieve that in an area with warm days and cool, damp nights. I have seen a boat tank go bad in a month, pumped pure alcohol into the carbs that had separated out and ruined the carbs.

[Husker]

Our turbines run on basically kernosene with an additive called prist