Lotus Elan

Conversion to non leaded fuel

PostPost by: Mrozik » Mon Jun 01, 2020 4:49 pm


Can someone advise what I need to do to the engine so that it will now take unleaded fuel?

Many thanks
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PostPost by: ericbushby » Mon Jun 01, 2020 6:44 pm

Hi john,
As I understand it, our engines have an aluminium cylinder head with hardened valve seat inserts already fitted, so no conversion is required. They are suitable for unleaded fuel as manufactured. No other parts are vulnerable so there is nothing to do.
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PostPost by: HCA » Mon Jun 01, 2020 7:47 pm

Change your flexible fuel pipes. Unleaded fuel contains bio-ethynol that is not kind to older fuel lines. Change them for modern fuel hose that is compatible with ethynol.
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PostPost by: s28ven » Mon Jun 01, 2020 9:24 pm

Have I not read somewhere that it is still advisable to use a lead additive to prevent smoking at idle due the lead sealing a small gap in the valve stem seals?
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PostPost by: rgh0 » Tue Jun 02, 2020 7:39 am

Lead deposits can help seal valve seats especially the exhaust but i don't think they help seal valve stems from oil leaks. In any case they would not deposit on the inlet valve stem which is where smoking at idle comes from.

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