In article ,
The Natural Philosopher wrote:
Trouble is, according to the classic car mags, the jury's out on
whether they actually work - unless they contain lead which most
don't. An old engine builds up a coating of lead and this can last for
a long time after the source is removed.

Not sure that a 50 year old agricultural engine would have run on leaded
petrol anyway.

All petrol had lead in it since roughly WW2 until the recent(ish) ban.

Very low RPM, usually low compression as well..most of the reasons to
put lead in were to do with squeezing extra power out of engines by
raising CR and RPM limits.

But had the added lubrication and cooling properties that allowed the use
of poor quality valve seat materials.

--
*If love is blind, why is lingerie so popular?

Dave Plowman London SW
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