Millers Oils (www.millersoils.net) has issued two very interesting Press Releases regarding modern fuel and oil developments that can have damaging effects on our cars.

Biofuel in petrol terms is BioEthanol, which can be found in as high as 85% concentration in modern 'environmentally friendly' fuels. The advice is, avoid it, because it can cause severe pinking and it attacks various components in the fuel line, from lead solder in your petrol tank to rubber, cork and plastic pipes, gaskets and membranes. Modern cars are built with other materials that are compatible with Ethanol and have sophisticated knock sensors to avoid pinking; classic cars would need major modifications and many new parts specially made to be able to cope.

ZDDP (Zincdialkyldithiophosphate) is an additive widely used in oils until recently. It provided extreme wear protection for metal components, especially camshaft lobes. However, its phosphorus content was found to be causing ash that damaged catalytic converters when it crept past rings and seals into the combustion chamber, so in modern oils it has been replaced with a different additive. Once again, all was done in conjunction with new car manufacturers who have changed the surface hardening specification for camshafts, followers, gears etc to cope with the new additive. Unfortunately the change is not so easy to accommodate for classic car restorers, who are finding that reground camshafts and new followers are often wearing away in the running in period, despite the use of apparently top quality modern oils. Millers contends that the problem is in fact the oils - but you'll be pleased to hear that Millers' oils (even the full synthetic ones) still use adequate levels of ZDDP.

Malcolm McKay, Motorbase News Editor