Classic cars forum & vehicle restoration.

[old iron]

I have managed to confuse myself, I have decided to use a mono grade oil in my recently rebuilt 1934 Austin engine. But I am unsure which grade to go for. My chosen brand is Comma who supply a SAE 30 but they say it’s for winter use, the SAE 40 grade would be the next choice but the spec’ tell me this is a ‘multi grade ‘. What to do?
Thanks

[peter scott]

You are certainly seeking to experience all aspects of vintage motoring.

Peter.
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http://www.nostalgiatech.co.uk
1939 SS Jaguar 2 1/2 litre saloon

[old iron]

I think it’s my age getting to me, been vintage motoring for about twenty odd years, seem to be forgetting more than learning,

[alastairq]

https://www.classic-oils.net/Morris-Golden-Film-SAE-40



Above as an example, but good stuff all the same...
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Dellow Mk2, 1951 built, reg 1952.
Fiat 126 BIS
Cannon special [1996 registered. Built in 1950's]
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Ford Pop chassis, Ashley 1172 bodyshell, in pieces.

[Miken]

You could go to the Comma web page and fill in the "Ask an expert" question form, Or better still, phone them up and ask for tech support. They wil know.

[mikeC]

I run a straight 40 grade in my Austin Seven all year round, but, yes, it would be usual to use 40 in the summer, and 30 in the winter.

If the oil is described as SAE 40 then it is not a multigrade oil; all multigrade oils are described with their hot and cold ratings, like 20/50, 10/30, or whatever.

With a pre-war engine with non-full-flow filtration, be very careful of using a modern high-detergent oil. If you are starting from scratch with a newly-rebuilt engine, and you know that all the oilways have been thoroughly cleaned out, then fine, but any residual contamination will soon be flushed out and may well clog the filter gauze without you realising it. This was the result of using a modern oil without thought in my Appia; the resulting engine rebuild was very expensive!


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in the garage: 1938 Talbot Ten Airline
Recently departed: 1953 Lancia Appia, 1931 Austin Seven, 1967 Singer Chamois, 1914 Saxon, 1930 Morris Cowley, 1936 BSA Scout, 1958 Lancia Appia coupe, 1922 Star 11.9 ... the list goes on!

[old iron]