Anyone run 100LL A gas in a 4-mix?

[lilspenny]

My owners manuals say to run unleaded gas, but ... Just wondering if anyone here has used 100LL Av Gas in a Stihl 4-mix or 2 stroke? If so, your impression??

 

[ammoaddict]

My owners manuals say to run unleaded gas, but ... Just wondering if anyone here has used 100LL Av Gas in a Stihl 4-mix or 2 stroke? If so, your impression??

Personally I wouldn't run that in anything. Breathing lead fumes is not healthy. I know it says low lead but it has a lot in it. We have 90 octane ethanol free fuel here. I mix it 32:1 with amsoil dominator in all my 2 strokes and my stihl 4 mix polesaw.

 

[lilspenny]

Personally I wouldn't run that in anything. Breathing lead fumes is not healthy. I know it says low lead but it has a lot in it. We have 90 octane ethanol free fuel here. I mix it 32:1 with amsoil dominator in all my 2 strokes and my stihl 4 mix polesaw.

I guess if I were to be worried about it I'd run mostly battery powered equipment, or at minimum Honda 4 stroke lead anchors.

 

[Mad Professor]

My owners manuals say to run unleaded gas, but ... Just wondering if anyone here has used 100LL Av Gas in a Stihl 4-mix or 2 stroke? If so, your impression??

If the exhaust has a catalytic converter it will poison the catalyst.

Personally I wouldn't run that in anything. Breathing lead fumes is not healthy. I know it says low lead but it has a lot in it. We have 90 octane ethanol free fuel here. I mix it 32:1 with amsoil dominator in all my 2 strokes and my stihl 4 mix polesaw.

I run 100LL in all my saws unless I'm milling or going to be running gallons at once.

The mix stored in 1-gal metal Coleman fuel cans stores forever and won't muck up the fuel system if left in the saws.

 

[EFSM]

My owners manuals say to run unleaded gas, but ... Just wondering if anyone here has used 100LL Av Gas in a Stihl 4-mix or 2 stroke? If so, your impression??

One of my commercial customers ran leaded fuel in his trimmers for a bit and then spent the next couple years cleaning little balls of lead from the spark plug electrode gap, even after switching back to pump gas.

 

[lilspenny]

One of my commercial customers ran leaded fuel in his trimmers for a bit and then spent the next couple years cleaning little balls of lead from the spark plug electrode gap, even after switching back to pump gas.

Gee! That's bad.

 

[Mad Professor]

One of my commercial customers ran leaded fuel in his trimmers for a bit and then spent the next couple years cleaning little balls of lead from the spark plug electrode gap, even after switching back to pump gas.

It does not deposit as "little balls", but as a coating of red lead oxide. A brush or emery cloth and the plug is good as new. It does not build inside a saw and "last for years"

I wear gloves fixing saws that run 100LL.

They are working on lead free AV gas. Current AV gas mix is ~4-5 less expensive than canned fuels. Current local airport price is $5.40/gal

 

[EFSM]

Gee! That's bad.

Yep, that’s why some people change airplane plugs at 25 hours.

 

[lilspenny]

It does not deposit as "little balls", but as a coating of red lead oxide. A brush or emery cloth and the plug is good as new. It does not build inside a saw and "last for years"

I wear gloves fixing saws that run 100LL.

They are working on lead free AV gas. Current AV gas mix is ~4-5 less expensive than canned fuels. Current local airport price is $5.40/gal

How about carbon? Is it worse than unleaded?

 

[Mad Professor]

Yep, that’s why some people change airplane plugs at 25 hours.

I'm still running German made Bosch plugs on 100LL.

Airplane might be less expensive, and better than crashing.

I've never had a saw loose spark from lead buildup.

 

[Mad Professor]

How about carbon? Is it worse than unleaded?

That is problems with mix, mix oil, mix ratio, or carb settings.

 

[Eager Beaver]

I have ran it a lot. Sometimes 50/50 with 87 non ethanol. No problems and my saws like it. Also, keeps along time.

 

[Bill G]

@Lee H runs 100LL

 

[Brad Button]

Using Avgas (like 100LL) in most 2-stroke engines is bad because its high octane and slow burn rate lead to spark plug fouling, sluggish performance, and deposits, while its lead content fouls plugs and can harm components, unlike the ideal ethanol-free pump gas designed for them. It doesn't vaporize well in lower-compression engines, causing issues, and while good for high-performance, tuned engines, it's generally not recommended for standard use due to these drawbacks.

 

[av8or3]

In a four stroke not designed for it, it will wreck the engine. Don’t believe me if you choose, but I work on aircraft. And, all the ope the people who work at the airport bring me when it stops working. Some of it can be saved, some of it cannot. You pays your money and you takes your chances.

 

[Mad Professor]

Using Avgas (like 100LL) in most 2-stroke engines is bad because its high octane and slow burn rate lead to spark plug fouling, sluggish performance, and deposits, while its lead content fouls plugs and can harm components, unlike the ideal ethanol-free pump gas designed for them. It doesn't vaporize well in lower-compression engines, causing issues, and while good for high-performance, tuned engines, it's generally not recommended for standard use due to these drawbacks.

Besides catalytic mufflers what does 100LL harm?

I've been using it in cars since the 1970s, I have SBC. at ~12:1 compression, 210lbs static compression.

In 2-strokes since they started "oxygenated" fuels, MBTE then 10% corn brew, since the 1990s.

I have no complaints other than red lead on spark plugs. I don't see that in my car.

 

[lilspenny]

Using Avgas (like 100LL) in most 2-stroke engines is bad because its high octane and slow burn rate lead to spark plug fouling, sluggish performance, and deposits, while its lead content fouls plugs and can harm components, unlike the ideal ethanol-free pump gas designed for them. It doesn't vaporize well in lower-compression engines, causing issues, and while good for high-performance, tuned engines, it's generally not recommended for standard use due to these drawbacks.

Thanks.

 

[av8or3]

I used to think the additional lead would help cool and cushion the valves. It was used as an anti-knock compound in autos (and aircraft as well) and worked great,at that. In the ope I see here the lead has built up to a point where the valves no longer seal. The engine won’t start. You can work the valves in and out with Kroil in the combustion chamber and sometimes knock enough loose that the engine starts. After running a tank of unleaded thru it it runs and will once again start.
The 100 Low Lead fuel contains SEVEN times the lead in it that Premium auto gas used to have in it. That’s a lot of lead. Most normally aspirated aircraft engines can be run on car gas, however, turbo equipped engines cannot be. Airplane engines (even the small ones) have huge valves and the lead is helpful in sealing and cooling and if it’s supercharged, absolutely necessary for the higher pressures developed in those “air cooled” cylinders. I wrecked an air cooled VW engine while experimenting with 100LL. It burned a valve so bad it fell back into the cylinder. It burned because the lead prevented the heat transfer from the valve to the head . Big mess. The other intake valves on that engine were impacted by lead at the seat. I mean almost stuck in the seat.
With your high octane engine requirement you have few choices but there is one available and as soon as I can remember what’s it’s called I’ll tell you. I used 1 quart to a tank of gas in the summer in my blown Corvette. I’m pretty sure Tolulene is a component. I remember it cost $50 for a 5 gal can. I’ll get back to you.

 

[av8or3]

Here’s something on Tolulene.

Google Search

I just happened to think. Coats your exhaust reddish brown.

 

[lilspenny]

I used to think the additional lead would help cool and cushion the valves. It was used as an anti-knock compound in autos (and aircraft as well) and worked great,at that. In the ope I see here the lead has built up to a point where the valves no longer seal. The engine won’t start. You can work the valves in and out with Kroil in the combustion chamber and sometimes knock enough loose that the engine starts. After running a tank of unleaded thru it it runs and will once again start.
The 100 Low Lead fuel contains SEVEN times the lead in it that Premium auto gas used to have in it. That’s a lot of lead. Most normally aspirated aircraft engines can be run on car gas, however, turbo equipped engines cannot be. Airplane engines (even the small ones) have huge valves and the lead is helpful in sealing and cooling and if it’s supercharged, absolutely necessary for the higher pressures developed in those “air cooled” cylinders. I wrecked an air cooled VW engine while experimenting with 100LL. It burned a valve so bad it fell back into the cylinder. It burned because the lead prevented the heat transfer from the valve to the head . Big mess. The other intake valves on that engine were impacted by lead at the seat. I mean almost stuck in the seat.
With your high octane engine requirement you have few choices but there is one available and as soon as I can remember what’s it’s called I’ll tell you. I used 1 quart to a tank of gas in the summer in my blown Corvette. I’m pretty sure Tolulene is a component. I remember it cost $50 for a 5 gal can. I’ll get back to you.

10-4 thanks.