SU Carburettors Ltd.
The thirties were a time of almost frenetic development; SU would and did make almost anything for anybody requiring a fuel system and the growth in output in both production and designs was quite incredible.
In 1936 the name of the company changed to SU Carburettors Ltd. In 1937 the thermostatic automatic choke and the ubiquitous H Type was introduced - a series of carbs with choke bores ranging from 11/8 th to 2 inches in 1/8th increments which were to be the standard right through to the end of the 1950s. In 1938 the hydraulic piston damper was introduced to provide acceleration enrichment.
Various new pump designs had also appeared by now including the HP, LCS and double ended high capacity models. By 1939 nearly all Morris and MG vehicles, Riley, Woleseley, Alvis, Bentley, SS etc were equipped with either an SU pump or an SU carburettor or both. SU was thriving.
In March 1939, according to a contemporary report, the SU factory covered 81,000 square feet and employed between 400 and 450 people making some 4,000 carburettors and 4,000 pumps a week plus quantities of aero-engine components. This year the zinc die-cast piston was replaced by brass, since zinc distorted or grew with age resulting in loose piston rods, and the HV type carburettor was phased out.
The Second World War
The second world war increased SU operations significantly - by the outbreak of hostilities the works employed some 700 people, an increase of 300 in about six months, supplying all the aero-carburettors for Rolls Royce Merlin, Vulture and Peregrine as well as Napier for their Sabre and Dagger engines. They also manufactured its fuel pumps for many military applications.
The dangers of this one factory supplying the entire aero-carburettor requirements of the RAF Spitfires, Hurricanes and bombers was realised in late 1939 and it was decided to set up a duplicate plant in the Riley works in Coventry.
Air raids in November 1940 caused damage to the works. In the first air raid the factory was set on fire, but this was contained and extinguished by the work's fire brigade, and although three high explosives scored direct hits, two in the machine shop, the carburettor production line plant survived intact.
In the second raid no bombs fell on the SU works itself but girders and other debris from surrounding buildings came through the SU roof and the Ministry for Aircraft Production decided to evacuate the factory. After only twelve hours' notice the first of many RAF trucks arrived to remove the plant to a modern, newly-constructed factory at Highlands Road, Shirley, recently requisitioned from the Co-op. Production continued non-stop during the move, however, any gaps being filled by the Riley shadow factory.
After the move the number of workers quickly rose to 1,500. The weekly output of carburettors was doubled after Dunkirk to 200 a week, with a normal working day of 8am to 7pm. This working day was voluntarily stretched quite often with the workers sometimes sleeping on the floor next to their machines.
A second shadow factory was set up in the Wharf Valley in Yorkshire in 1941, in the village of Barwell, a boot factory requisitioned for the purpose. As well as the SU, this factory made the Rolls Royce Bendix Stromberg type carburettor.
In 1942 the petrol injection pump was developed for the aero-engines, first fitted on Mosquito aircraft. Two SU technical staff had taken out a patent in 1939 but the firm could not get anyone interested in it at that time. After three years of neglect, the SU design was adopted and the new British petrol injection pump came into general use in the last year of the war. It was later built under licence by an American company and called The Simmonds Injector Pump.
Growth and Decline
In 1945 the production of carburettors and fuel pumps for motor vehicles was resumed and a move to the present site at Wood Lane, Erdington, Birmingham took place in July 1947. The Skinner connection was finally severed this year when Morris (Lord Nuffield) called a meeting with Carl, along with eight other directors from various parts of the Nuffield Empire, and announced their retirement. Carl was aged 63 by now but it was never the less a rather sad end to a career dedicated to the development of his brother's ingenious invention.
The following year saw the introduction of aluminium die castings replacing zinc and brass, a direct result of experience gained during the war years and making good use of the plentiful supplies of aluminium left over from aircraft production.
After the war, developments and new introductions came almost on a yearly basis. In 1950 dust proofing was introduced, in 1952 the formation of the British Motor Corporation widened the market for SU carburettors and pumps still further, and in 1954 were introduced both the part-throttle weaker for single car applications on 6-cyl engines (e.g. Rover P4) and the HD type carburettor.
1958, the year Carl Skinner died, saw the introduction of the HS type carburettor and new high pressure electric pumps. In 1962 the delrin float needle was introduced and the following year the nylon float on HS carburettors. 1967 saw the development and marketing of a mechanical fuel pump and shortly after an automatic enrichment device (AED).
In 1969 the spring-loaded metering needle and throttle overrun valve were introduced, in 1971 jet temperature compensation on HS8 carburettors, and in 1972 the HIF type. Jet temperature compensation was expanded to HS4 and HS6 carburettors in 1975; the following year the ball-bearing suction chamber was introduced and the part throttle weakener further developed.
By 1976 SU's position, that of a small plant in a rapidly declining car manufacturer known as British Leyland Motor Holdings, changed once again when it became part of a division of Service and Parts known as SU/Butec.
With the demise of SU/Butec a few years later, SU lost its identity to become Austin Rover Fuel Systems, the beginning of a long period of drift and decline with SU parts becoming more and more difficult to service.
SU History Continued
In 1982 SU introduced the HIF44E carburettor, which had electronic control of the cold start function, idle speed and overrun fuel cut-off. In 1988 the company was acquired by the Hoburn Eaton Group, who themselves were acquired by the large USA based multinational Echlin Corporation eighteen months later. The Echlin Corporation granted SU true independence, being solely dedicated to automotive components.
The name SU was brought back to the forefront, and the company now trades as SU Automotive.
January 2001