TEL - Tetraethyl lead

[KNorton]

Considering my bike was built in 1971 when leaded gas was favored, what do I do about adding lead to my gas? I used lead for a while in the early 90s when you could find it but when Auto Zone stopped selling TEL in a bottle I had to use unleaded. The car ate 2 valves because of it. I don’t want my Commando doing that!

What do you guys do?

 

[hhh]

Your car likely had valve seats cut directly into the cast iron of the heads which relied on the lead to enhance cooling and add a protective layer. That said, I've not noticed anything in my cast iron head classic cars with respect to seat recession. In British bikes of the sixties and later, Commandos included, the head is aluminum so it already has hardened austenitic iron seats which seem to do just fine with unleaded.

 

[htown16]

Nothing to worry about. Have used unlead, e10 even in my Brit bikes for the last twenty years. No issues. Wonder how many valve seats have been done over the years for absolutely no good reason.

 

[KNorton]

Thank you! Hhh, you’re absolutely right. It was a ‘69 Mustang (my pride and joy) with cast iron heads. I never even considered the Commando head being aluminum. Nothing to worry about. You guys just took a huge weight off my book! I feel much better now!

 

[MexicoMike]

I ran a Mopar 340 in a '68 Fastback Barracuda for 20 years on unleaded gas - no issue at all.

 

[marshg246]

Considering my bike was built in 1971 when leaded gas was favored, what do I do about adding lead to my gas? I used lead for a while in the early 90s when you could find it but when Auto Zone stopped selling TEL in a bottle I had to use unleaded. The car ate 2 valves because of it. I don’t want my Commando doing that!

What do you guys do?

IMHO, E10 is easier on your engine than E0 unleaded - just use pump gas and don't worry about it.

Of course, it's not good for a Fiberglas tank and if you let it sit with little gas in the tank water can form at the bottom of the tank so it's best to ride often or at least keep tank full.

 

[acotrel]

With an internal combustion engine - the following things are in balance - combustion ratio, ignition advance jetting and fuel type. A change in any one of these requires adjustment of the others. Adding TEL to petrol should not substantially change its calorific value or its latent heat of vaporisation. The adjustment for a different fuel type is usually by changing ignition advance or jetting. The effect on valve seats is more likely to be due to heat, than lead. TEL is volatile. If it is burned, it might leave a lead deposit. It would be more noticeable on the valve seat on the exhaust side, unless that was hot enough to evaporate the lead. When engines are tuned for maximum power - fuel mixture is usually either leaner or the ignition timing is more advanced - more heat is often developed.

 

[htown16]

Be glad that TEL was outlawed. It was some bad $hit. This guy probably created more deaths and illness than any other single individual.

Thomas Midgley Jr. - Wikipedia

en.wikipedia.org

 

[Tornado]

According to the internal combustion engine history pages...TEL was introduced as a knock/pinking inhibitor aka octane booster and not so much as an anti-wear additive. Prior to TEL, Ethanol was actually used as an anti-knock additive...so we've come full circle in a sense!

 

[JimNH]

Big deal now is getting lead out of Avgas. Even though it says 100LL (Low Lead) there's still a lot of lead. It's LL compared to the 100/130 green gas it replaced. Spark plugs, especially the lower ones in the cylinder can get quite fouled if proper leaning isn't done. I usually clean them every 50 hours or less with the oil change, lead accumulates in the oil due loose clearances of the air cooled engine. The crankshaft/prop shaft on airplanes with controllable props is hollow. The hollow shaft acts like a centrifuge and when you remove the prop the shaft will be quite full of lead spun out of the oil. Sludge traps on leaded gas will be full as well. Lead lubricating valve stems is total BS. As was already said: anything with a replaceable seat is probably fine especially if replaced in the last few decades.

There are some no-lead aviation gas products on the market but most engine manufacturers have yet to give blanket approval. The FAA has made approval via STC or Supplementary Type Certificate but none have an ASTM number.

There used to be 115/145 purple avgas for high performance engines but it seems to have disappeared. When I was a young A&P mechanic the military was still using it and the company I worked for had an Army contract. The Army had stupid rules that said no leaning below 5000' so since most of their flying was low level on 115/145 the plugs would be so totally fouled they just couldn't be cleaned, just thrown away.

Lead is bad news for a number of reasons. Don't worry about using no-lead mogas, as long as the octane is sufficient for your compression and spark advance you'll be fine.

 

[Torontonian]

Be glad that TEL was outlawed. It was some bad $hit. This guy probably created more deaths and illness than any other single individual.

Thomas Midgley Jr. - Wikipedia

en.wikipedia.org

Wow. Always knew lead was bad . Thanks for the link .
The Romans found out with infertility and insanity , as they lined their aqueducts with hammered lead to stop leakages .
As a teen I got it on my hands as dust ,using a pellet gun . Also biting down on sinker weights for sportfishing . Smarter now .
I'll watch the UTube now , Thomas Midgley Jr .
Thanks .

 

[marshg246]

Also biting down on sinker weights for sportfishing . Smarter now .

My family fished a lot - who could imagine any other way to close a split sinker

You also probably melted car wheel weights to make sinkers - my father certainly was not going to buy what we could make basically for free!

Other fun things from the past was playing with Mercury an in the southwest buying rock collections at roadside stands and them having Uranium and/or Radium wrapped in tin foil.

 

[MikeG]

I cast my own round balls and maxi balls for years.

 

[grandpaul]

I've splashed gas all over my hands since I was 14, and used R-22 for over 20 years.

"It is appointed to man, ONCE, to die."

 

[Fast Eddie]

Be glad that TEL was outlawed. It was some bad $hit. This guy probably created more deaths and illness than any other single individual.

Thomas Midgley Jr. - Wikipedia

en.wikipedia.org

A very interesting article!

In his defence however, I think that when he concluded that “1 part tetraethyl lead per 1300 of gasoline could safely be used” he was talking about a scale of usage very different to today as he had no idea just how ubiquitous car ownership would become and what city traffic etc would look like in the future.

 

[marshg246]

A very interesting article!

In his defence however, I think that when he concluded that “1 part tetraethyl lead per 1300 of gasoline could safely be used” he was talking about a scale of usage very different to today as he had no idea just how ubiquitous car ownership would become and what city traffic etc would look like in the future.

Or that many other devices would be used that used gasoline and many of them were seldom/never serviced and leaked/exhausted raw gasoline. We even used gasoline to start camp and cooking (outdoor grill) fires as it often cost less than proper starters or we were lazy. I got set on fire when I was 14 with gasoline while starting a grill - lucky to have lived - I can tell you every second of that experience even today.

 

[acotrel]

One of my qualifications is in occupational hygiene. Studies have been done which indicate that lead in petrol adversely affects intelligence. I have washed motorcycle parts in Avgas, and I have not noticed a difference.
My mate proved to me that Avgas is safe - he threw a lighted cigarette into a tray full of it, while were in a small workshop. He also proved that nitromethane is safe, when lit with a match - it burns slowly. He doesn't know about 'critical height', and I would never tell him. The most dangerous place in an explosives factory is the burning ground, if gun propellant is stacked too high. It burns slowly at first, but the burning rate is exponential - it contains nitroglycerine.

 

[JimNH]

Some of the FAA's own publications in the past recommended washing parts in Avgas. As a mechanic it was common for me and others to take a little gas from the plane's quick drains to clean a part or tools. My hands were constantly covered in it. I could have been a genius! Moving on to turbine equipment Jet A was nowhere near as useful. If you did any fuel system work you smelled like an oil burner serviceman. Working on my own plane I still use Avgas occasionally for a quick clean of a small part. The plane's belly behind the exhaust stack gets a coating of oil/lead that needs a wipe of mineral spirits then 409 cleaner to remove. I no longer use Avgas but the damage is probably done.

More Avgas cleaning: The company I worked for in the '70's had a contract with the FAA to provided coverage on their flight check planes. At the time they were using C47s (DC 3) for airway and instrument landing systems flight checks. They had their own mechanic and every night when they returned to base and cooled down he would drain some gas into a pump can and wash down the 1830 engines. When he was away on vacation the crews would report oil leaks and we would be tasked with fixing myriad leaks on the big radial engines, a near impossible task. If a radial isn't leaking there's probably no oil in it. No worry about running out, the oil tanks held 30 gallons.

 

[Triton Thrasher]

lead in petrol adversely affects intelligence. I have washed motorcycle parts in Avgas, and I have not noticed a difference.

You should ask your friends if they’ve noticed.

 

[acotrel]

Many years ago studies were done by testing school kids' cast-off teeth for lead content, and the results were compared with IQ tests. It was done at a school near Kingsway in Melbourne Victoria. I think they concluded that lead has an effect on IQ. IQ tests are not as accurate or as precise as the chemical analysis of lead content. We Australians are mostly pretty dumb. We do not even know much about cricket.