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Alcohol in fuel, old style

Tom Gaynor

Well Known and Active Forum Website User
VOC Member
Reading the fuel cap of my 1938 Rudge, as one does when polishing, I realised that engraved on the cap was "For best results use: alcohol mixture ethyll fuel benzol mixture" which suggests that alcohol in fuel is scarcely new. The carb is a brass TT, bought by the factory (I have the purchase order signed "George Hack") in 1934.
On my way to work in the 1960's I now remember seeing billboard advertising "Cleveland Discol" and listing the advantages (cool running?) that petrol plus alcohol gives. Personally I've always preferred my alcohol separately...


Well Known and Active Forum Website User
VOC Member
Tom, one advantage of adding a toddy to the petrol is it can assist in removing water in the tank. The Benzol (Toluol) is nasty stuff but I know some people who still use it. At one stage I was working in a printing ink factory and gallons of the stuff used to "vapourise".....(straight into petrol tanks).

roy the mechanic

Well Known and Active Forum Website User
VOC Member
pre-war fuel was not very good,that's why most engines of the period were typically around 6 or 7-1 compression. i'll bet the rudge is high compession and nearly a "dizzy" 8-1! the alcohol additive would help to avoid pinking+ valve "troubles".

Alan J

Well Known and Active Forum Website User
VOC Member
During the "Suez crisis" me dear old uncle Stan, got his old Austin 10 home he told me, by pouring a bottle of whisky into the fuel tank!!I hope it was not a single malt!


Well Known and Active Forum Website User
VOC Member
This alcohol must be bad stuff. I have done several samples and it has never measured no more than 5% here in the Northeast U.S. That is a lot of damage for such a small amount. Personally, I have not had any difficulties, but if I did, I would simply remove the alcohol. I know one member who does that for all of his small engines and tractors. It is not much help with the bikes unless you can manage home runs.

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