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Lead Additive?


McGill

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When I bought my B110 about three years ago the dealer told me that I needed to use lead additive, which I've been doing. Now, a local dealer told me I don't have to. Who is correct?
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Mcgill I wouldn't worry about using an lead additive as I havn't been using any sense they stopped using lead in there gas. Besides from what I have heard and read it causes more carbon build up the additive does I mean. I also read that you can add about 3 tablespoons every 3rd gas tank of Mystery Oil but it also will cause more carbon build up also to which means cleaning the head and combusion chamber more often. Hopefully others will add to this as this is just my opinion from my experience. Good Luck >>->happyjack<-<<
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I'm not sure I remember correctly, but --- lead was added to gas to retard detonation. When catalytic converters were first used on cars (in '73?) both leaded and unleaded gas was available. The unleaded gas used a different additive to retard detonation. Leaded gas was said to plug or destroy cat converters. Unleaded gas was said to harm older engines that relied on lead as a lubricant for the valves (I was always curious about that because for years Amoco's sales pitch was that their "white" gas contained no lead). As the years passed, it was said that reformulated additives in unleaded gas also lubricated the valves in older engines. Am I remembering correctly? Was the lead/valve fear b...s... or true? Was the reformulation b...s... or true?
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I have been told that you do not want to use Gasahol in small engines, because it dries out the valves or something. Is this true? Or was somebody consuming a little too much alcohol himself? I know that this winter both my tractor and myself could maybe have been helped by a little alcohol. Years ago, they raised the price of gasoline when they added the tetraethyl lead. I always heard that it helped top end lubrication. In 1974, when they came out with the catalytic converters, the lead would have reacted with the platinum, which is the catalyst. So what did they do, they took the lead out and raised the price! Is there any truth to the need for top cylinder lubrication? It kind of bothers me as I have already used up three cans of starting fluid this year.
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I believe the only reason to use lead in old engines is for heat transfer on the exhaust valve. The lead helped transfer the heat to the valve seat and prevented the exhaust valve from burning out prematurely. I believe most of the engines that we talk about in this website have the stellite or similar exhaust valves/seat that do not require the lead or substitute. MS
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When lead was discontinued and cast irons were still the norm we still did not notice any unusal problems or excessive wear even in the older blocks without seat inserts.
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