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  #1  
Old 08-10-2003, 04:15 PM
WowS500
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Lead additives

The classic cars ran on leaded gas, however leaded gas is not sold any more and lead additives have to be used.
Has any one used or are using this. If so where does one get this from and any brand recommended.
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  #2  
Old 08-10-2003, 04:31 PM
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Location: Evansville, Indiana
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Not available legally and not very smart to use -- lead oxide is an abrasive and will grind up your engine's inwards (the main reason cars used to last only 100,000 miles or less), it is big time toxic, absorbed through the skin, causes irreversable brain development problems/mental retardation in kids, and isn't necessary in modern fuel.

Use Premium 92/93 octane, you don't need more.

Peter
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1972 220D ?? miles
1988 300E 200,012
1987 300D Turbo killed 9/25/07, 275,000 miles
1985 Volvo 740 GLE Turobodiesel 218,000
1972 280 SE 4.5 165, 000 - It runs!
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  #3  
Old 08-10-2003, 04:35 PM
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lead add itive is perfectly legal and harmless!

You may have gotten wrong information regardig above. Any auto store carries LEGAL lead addittive. I use this on my 1963 corvette and have had no problems. It is rated safe and acceptable and contains a few other addittives that help combustion and possibly save valve insersts (unless you have hardened valve inserts and dont need to use lead additive. Abe G
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  #4  
Old 08-10-2003, 04:38 PM
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Does the label say "tetraethyl lead" anywhere? I've seen plenty of "lead additive replacements" and "octane boosters", but none that actually contain tetraethyl lead.

I wouldn't use it any more than I would keep sodium cyanide solution around the house.

Peter
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1972 220D ?? miles
1988 300E 200,012
1987 300D Turbo killed 9/25/07, 275,000 miles
1985 Volvo 740 GLE Turobodiesel 218,000
1972 280 SE 4.5 165, 000 - It runs!
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  #5  
Old 08-10-2003, 05:13 PM
WowS500
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Peter, one of the products I came across does contain TEL "tetraethyl lead"and also mentions that it is environmentally safe and EPA registered.

IS LEAD SUPREME-130 SAFE FOR THE ENVIRONMENT?
By adding Lead Supreme-130 to your fuel, your engine will perform better by increasing horsepower and burning the fuel more efficiently. Practically all the lead content is burned and deposited on the valves and valve seats, leaving the environment virtually lead free. The sun quickly decomposes any remaining trace of lead.
HIGHLIGHTS OF LEAD SUPREME-130
1. The only product with 100% Tetraethyl Lead and other octane enhancing components (No substitute chemicals added).
2. Boosts octane from 2-16 points when added to fuel. Perfect for HIGH COMPRESSION ENGINES. Eliminates engine knocking.

3. Protects valves and valve guides.
4. EPA registered.
5. Environmentally safe
6. A superior gasoline treatment.
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  #6  
Old 08-10-2003, 06:55 PM
I told you so!
 
Join Date: Jun 2002
Location: Motor City, MI
Posts: 2,791
Quote:
Originally posted by WowS500
Practically all the lead content is burned and deposited on the valves and valve seats, leaving the environment virtually lead free. The sun quickly decomposes any remaining trace of lead.
WHAAAAAA??????????

Decomposes to what????

So, the lead just accumulates in the engine until you have huge blobs of lead around the ports, never to leave the exhaust pipe!!!! Where did you read this baloney?????

I agree with Peter on the toxicity of TEL. The stuff is readily absorbed by the skin. I would carefully look at the MSDS before using this product.
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  #7  
Old 08-10-2003, 10:12 PM
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newer lead subsitutes are just manganese compounds.
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  #8  
Old 08-10-2003, 10:48 PM
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NO organometallic compound is GOOD for engines.

The nonsense about safety and EPA approval is hogwash -- EPA specifically prohibits the use of lead in fuels for sale, and does not, to the best of my knowledge, approve or dissaprove of fuel additives for consumer use.

The idiocy about lead being "good" for engine parts is hogwash too -- this was propaganda bandied about by the American automobile companies to avoid putting inserted valve seats in cast iron heads, nothing more. The theory was that a layer of lead oxide on the valve and valve seat would "wear itself" as a permanent self-ablative coating rather than the valve or seat.

That turned out to be wistful thinking at best. Lead oxide, like all metal oxides, is considerably harder than any metal found in an automobile engine, and will grind away constantly. The oxidation of tetraethyl lead will produce microscopically fine, breathable, lead oxide dust -- this blows out the tailpipe as well a fusing to things like exhaust valves and spark plugs. It also gets into the oil, and very fine particles will circulate right through the filter, so they constantly "polish" the bearings, cylinder wall, and valve train.

I rememember lead fouling -- under load, the lead oxide melts and shorts out the plugs. Happened all the time to "gear heads" who just had to have 13:1 pistons and over-advanced timing.

Lead will also instantly poison a catalytic converter and render it totally ineffective. This is not good -- I also remember the stench of semiburned hydrocarbons in LA and Germany before all cars had cats. Not very nice, bad enough to make your eyes (and lungs) burn.

Any modern engine will run fine on commercial lead-free premium, you aren't going to get any improvement by adding lead to the fuel.

Peter
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1972 220D ?? miles
1988 300E 200,012
1987 300D Turbo killed 9/25/07, 275,000 miles
1985 Volvo 740 GLE Turobodiesel 218,000
1972 280 SE 4.5 165, 000 - It runs!
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  #9  
Old 08-10-2003, 11:25 PM
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There were no post war MBs that required leaded gas as they all had hardened valve seats.

The problem with leaded gas had nothing to do with its toxicity the stuff they are using now is supposedly a lot worse. The problem with lead is what it does to the inside of a catalytic converter. On the atom level it bonds with the platinum defeating its activity as a catalyst. The amount on the surface probably could only be seen with an electron microscope as only a few atoms thick totally kills the catalytic action.

So, whether it is legal for some use, it is ABSOLUTELY NOT legal to add to any car in the US that has a catalytic convertor.
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  #10  
Old 08-11-2003, 09:55 AM
I told you so!
 
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Quote:
Originally posted by psfred
....The idiocy about lead being "good" for engine parts is hogwash too -- this was propaganda bandied about by the American automobile companies to avoid putting inserted valve seats in cast iron heads, nothing more. The theory was that a layer of lead oxide on the valve and valve seat would "wear itself" as a permanent self-ablative coating rather than the valve or seat.

That turned out to be wistful thinking at best. Lead oxide, like all metal oxides, is considerably harder than any metal found in an automobile engine, and will grind away constantly....
A good post from Peter, but part of it doesn't make sense to me. If lead oxide is indeed abrasive, and the theory of lead oxide self-ablating the wear surfaces is indeed hogwash, then why are all engines now manufactured with hardened valve seats?
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  #11  
Old 08-11-2003, 10:39 PM
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Kestas:

No choice but to use inserted seats in an aluminum head, and there is this little thing called emissions warrenty. Engine HAS to last 50,000 miles without anything but "normal maintenance" or the producer has to repair it. Otherwise we would still be doing valve jobs at 25,000 miles and a bore and hone at 75,000!

As far as I know, only American engines with cast iron heads still have directly machined valve seats -- everyone else uses aluminum heads.

Besides, did you ever actually SEE an engine that required a valve job simply because the owner used unleaded fuel? I haven't -- unleaded makes the engine last longer!

Peter
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1972 220D ?? miles
1988 300E 200,012
1987 300D Turbo killed 9/25/07, 275,000 miles
1985 Volvo 740 GLE Turobodiesel 218,000
1972 280 SE 4.5 165, 000 - It runs!
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  #12  
Old 08-12-2003, 10:43 AM
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Join Date: Jun 2002
Location: Motor City, MI
Posts: 2,791
Not all heads are made of aluminum. Those heads still made of cast iron have induction hardened valve seats. I had the good fortune to visit the factory where the GM 3800 engine was made and see the hardening operation. I've also been paid good money by Ford to audit their induction hardening practise on valve seats in their factories. The owners manual of my 71 Cutlass makes a point in telling the owner that the engine has hardened valve seats and is okay for running unleaded. Manufacturers wouldn't be adding such an expensive step to their manufacturing process if there wasn't some truth to needing hard seats. So there is something about lead in gas that lubricates - rather than abrades - the valve seats in older engines.

Regardless of the fact that heads now run with hardened valve seats, I agree with you that it's not that big a deal for older cars. Consensus among the Cutlass owners on the Oldsmobile forum is that hardening the seats is only necessary if you run a car hard.

Valve seats are not an emission component and I doubt they are covered under emission warranty.
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  #13  
Old 08-12-2003, 12:47 PM
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Location: Northern Calif. (Fairfield Area)
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WOWS500,

This is a very interesting thread. I'd like to make a few comments based on being an avid reader and having a service facility about 5 miles from the Chevron research center for many years. There is also a large Ortho research center next to it. Through the years some of the chemical engineers were my customers. I particularly remember one gentleman by the name of Heinz Webber. Boy, don't try to tell him anything about gasoline. These gentlemen were always willing to answer my questions.

Lead was used to protect valve seats. This protection was needed in engines that didn't have seats that could handle the heat. As someone pointed out you don't need the protection for around town driving. The lead stayed on the seats for awhile even after switching to unleaded.

When the lead was taken out of fuel you could legally buy phosphate based additive, but it had to be added with every tank. I'm assuming it is still available for older cars that haven't been upgraded.

Also in the interest of the environment, all aromatic hydrocarbons were removed. All truckers can tell you exactly when that happened. Three things happened when these were removed. Octane rating went down in gasoline. Cetane rating went up in diesel. All the worn seals that weren't made of viton in diesel injection pumps shrank and allowed them to leak. All these seals would have leaked earlier in life if they hadn't remained swollen in the presence of aromatic hydrocarbons.If you want to boost your octane or stop an old diesel pump from leaking, go down to your chemical supply house and buy a gallon of technical grade zylene. You will have to fill out a form saying you won't make bombs or dope and give them about ten bucks.

Lead is not only a health hazard, it fouled plugs and carboned up the engine. The removal of lead from fuel is why we have all these new split fire and multi electrode spark plugs on the market today. In the old days plug manufacturers sold their plugs at cost to the engine assy plants, because there was a very good chance the consumer would request that brand in 10,000 miles for the tuneup. There is where the money was made. Now with 50,000 mile plugs, sans the lead and people keeping cars longer, that link is gone. So now plug makers have convince buyer that their newest multi electrode plug is far superior to what the competition has.

We are so used to the exhaust of the modern cleaner burning engines that we need to be reminded once in awile when we are standing next to an oldie from the 50s or 60s. My eyes start wattering, not so much from nastalgia, as from the fumes that are burning my eyes.

my 2 cents,
Peter
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  #14  
Old 08-13-2003, 10:15 PM
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Hardend valve seats make both seat and valve last considerably longer than "plain" valve seats ground into a cast iron head.

Part of emission certification includes long term operation of the engine to certify that the design will meet emission requirements at extended milage (or you can guess what they would run like in 15,000 miles!), and "soft" valve seats will be leaking enough at 50,000 that compression is way low. Low compression = high CO/HC, so there you are.

Even hardened seats and stellited valves wont' last forever -- the compression in "old blue" at work (92 Chevy V6 van with 350,000 miles) is down to about half spec -- doesn't use oil, so I suspect worn out valves. However, new valves would probably result in a blown rod or crank is short order -- I believe the only reason it still runs is that the power output is so low.

Besides, do you really think GM or Ford could sell a car in this day and age that required a valve job at 25,000 miles? Get real! Most people I know get exercised at the thought of brake work at 25,000 miles, let along the thought of engine repairs.

Peter
__________________
1972 220D ?? miles
1988 300E 200,012
1987 300D Turbo killed 9/25/07, 275,000 miles
1985 Volvo 740 GLE Turobodiesel 218,000
1972 280 SE 4.5 165, 000 - It runs!
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  #15  
Old 08-14-2003, 03:07 PM
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Back in the 1970s when cats first appeared, MB published that every engine they'd ever built would be fine with unleaded fuel.

Some interesting (if shrill) info on this subject:
http://www.thenation.com/doc.mhtml?i=20000320&s=kitman&c=1
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