The flex hose for the oil pressure gauge signal line was originally a Smiths hose. Modern replacement parts commonly have construction similar to the fuel hoses with stainless steel braid covering, but original parts were much different. The original oil pressure hose had cloth braid on the outside of a small bore rubber hose, then had a steel wire spiral wrapped around it for protection and form holding (similar to the temperature sensor tube). One of the brass end fittings was stamped with the maker's trade name "Smith's Super-Flex".

Original Smiths Super-Flex oil pressure hose

On 06 April 2017, Garry Kemm in Victoria, Australia wrote:
"S.Smith & Sons (England) Ltd. was a parent company and their subsidiary companies included Petro-Flex Tubing Co. Ltd.   Petro-Flex manufactured both petrol and oil tubing. ... Sometime late 1950's the design was changed to a steel braided version which was the same (at least externally) as the petrol hoses. The Smiths PetroFlex oil hose part number is PFP 195. The attached photo is of an original oil hose from a 1959 MGA Twin Cam, and it can be seen that externally it is the same as the original Petro-Flex petrol hoses, that is braided zinc plated steel".


BMC part numbers:

MGA 1500
83866 - Pipe - flexible - for connector to engine

MGA 1600
AAA627 - Pipe - connector to engine (flexible) ---
Standard model. Part No. change; was 83866

AHH5820 - Pipe, connector to engine (flexible)
Twin Cam and standard all round disc brake model Com. (c) 91240