In article .com,
robgraham wrote:
I've been given an elderly (40-50 years) cultivator - 4 stroke Briggs
and Stratton single cylinder engine. Seems to be all OK and the
engine runs fine. However I believe I should be adding something to
the petrol to make it equivalent to that containing lead.

A local agricultural machinery company said this wasn't necessary, but
a decoke would be advisable.

What's the collective's opinion please ?

It really depends what the exhaust valve seat consists of. If it's part of
a cast iron block or cylinder head you might well have problems, but even
then not always. If the material the seat is in is aluminium it will have
a steel insert which is almost certainly hard enough.

--
*I have plenty of talent and vision. I just don't care.

Dave Plowman London SW
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