The 6/80 & MO Oxford & Cowley Club

Content provided by Patrick Carroll (HM39), Honorary President

Introduced at the 1948 Motor Show, the 4/50 is the smaller brother to the 6/80, with a 1500cc 4-cylinder engine in place of the 6/80's 2200cc. Apart from the extra bonnet and wing length on the 6/80, the two cars are virtually identical, but externally the 4/50 has a narrower radiator grille, and only 1 ancillary lamp on the front valance.
Staying outside the car, the 4/50 is identified by shorter front wing flanks between the wheelarch and 'A' post, and by the lack of opening rear quarter-light windows. It also ran on slightly narrower tyres - 5.50 x 15 against 6.00 for the 6/80.
The 4/50 cost £904 at it's introduction, and could have expected to be a sales success, as there was little competition at this price level. However, it's sales between 1948 and 1952 were disappointing at only 8,950 against 25,280 for the larger 6/80 for it's full production run, so the 4/50 was discontinued in November 1952, making way for the technically simpler 4/44.
Under the bonnet, the 4/50 and 6/80 engines are of similar design, but the 4/50 has a manual choke as opposed to the 6/80's electric unit, using an auxiliary carburettor; a single 1¼" SU main carburettor is used on the 4/50, with the 6/80 having a twin set-up; and the 6/80 camshaft has a damper at the back which is not fitted to the 4/50.
The engine design is unique to the 4/50 (4 cyl) and 6/80 (6 cyl) the valve train of which is based on that of a V8 aero engine (The Wolseley Viper engine which powered the SE5A Biplane, made by Vickers who controlled Wolseley at that time) which Wolseley produced under license from Hispano Suiza during WW1. It is an under square low compression unit.
This is often mis-quoted as "Longstroke" however, although the stroke is slightly longer than the bore, it is far shorter than many contemporary marques of the era which had very narrow bores and far longer strokes, thus it is "short stroke" in comparison and should be more correctly termed as "under square".
All the engines have a single overhead camshaft operating directly onto the valves. Split helical gears drive the camshaft from a vertical shaft that also operates the oil pump at the bottom, and the distributor at the top.
It is important for any prospective 4/50 purchaser to be aware that some engines were known to have experienced cases of the exhaust valves burning out after what might be considered a relatively low mileage.
There has always been much engineering debate as to why some engines were affected and other units not. It would seem a fair comment to say that a combination of how the valves and their guides operate within the engine, combined with the specific materials they were manufactured from, and the kind of use the vehicles received probably resulted in this issue.
The good news is that any Wolseley 4/50 engines unfortunate enough to have experienced any valve problems will probably by now have already been rectified. In many cases owners had their valves 'Stellited' - a process also used by the Police, which entails valves being coated with an extremely hard and virtually indestructible coating.
In addition, for the benefit of its members The 6/80 & MO Club has commissioned the remanufacture of exhaust valves for both Series I and Series II engines in high grade stainless steel. It is still possible to find a genuine low-mileage car where no additional engine work has been carried out; however, if previous owners have maintained their cars well (as they often did years ago) then there may not necessarily be any cause for concern.
Opinion differs as to whether the Series II engine was actually an improvement over the Series I unit. However, with a well maintained engine, the Wolseley 4/50 can be a very easy car to live with. Not having to maintain the balance of the bigger 6/80's twin carburettors has distinct advantages for the 4/50 owner, and its ability to keep pace with modern counterparts on the road can make for an altogether satisfying driving experience.
The body was the first post-war design from Morris/Wolseley, being mono-construction as opposed to the pre-war separate chassis, and all the Club cars share the same basic design and body style as the Morris Minor 'MM'. Rear suspension is by semi-elliptic leaf springs, and the front has torsion bars splined into wishbones.
The trunnion and swivel-pin set up of the front suspension was common to many other vehicles of the time - although in the case of the Wolseley 4/50 probably over-engineered to some degree to cope with the weight towards the front of the car. As with any set-up of this design, the key to reducing any wear in the trunnion internal threads and swivel-pin external threads is to ensure they are greased at the prescribed servicing intervals.
Even when this appears to have been carried out satisfactorily, blocked grease-nipples and the failure for the grease to find its way around every component can reduce the life expectancy of these items.
Shock absorbers were Armstrong hydraulic lever arm type on early cars, but modifications were made soon after introduction, to fit telescopic types (twin at each front wheel, and singles at the back).
Brakes are efficient Lockheed hydraulic all round, with twin leading shoes at the front.
The 4-speed gearbox has synchromesh on 2nd, 3rd and 4th, and is operated by a column-mounted lever. Drive is through a single plate Borg & Beck clutch, prop shaft, and universal joint, to a semi-floating hypoid rear axle. A 1949 road test report quotes the car's 0-60 mph time as 31.6 seconds, and the average fuel consumption of 26 mpg.
Internally, the Wolseleys were a little up-market from the Morris's, with a walnut dash and door cappings, but all versions had leather seats with Dunlopillo foam, and carpeting throughout. Instrumentation consists of a speedometer, clock, and gauges for oil pressure, fuel and amps.
Any engine (regardless of manufacturer) which is allowed to overheat will also create additional cylinder head problems. Had the manufacturer seen fit to incorporate a temperature gauge as standard equipment, then early indications that the engine was getting too hot would have been spotted by the driver well beforehand.
The earlier engines were designated as the Series I, but towards the end of 1952 a redesigned cylinder head and cooling system were introduced, incorporating enlarged waterways, and valves which were slightly longer and designed to work at an improved angle. This later engine became known as the Series II, and in the case of the 4/50 commenced with engine number 10501-2.
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