New Bedford Engine and Two-speed Axle
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THREE important innovations are announced today by Vauxhall Motors, Ltd. They are a new four-cylindered oil engine, a Vauxhallbuilt two-speed axle, and the introduction of moulded brake facings on all vehicles except the 10-12-cwt. models.
The new engine, which is available in Bedford 25-cwt., 35-cwt., 2-ton and 3ton chassis and replaces the Perkins P.4 engine, is a 200-cu.-in. (3.27-litre) unit. ills essentially a four-cylindered version of the Bedford six-cylindered engine which was introduced last February. More than 6,500 of that unit have been built since that time.
It is a direct-injection engine with gross and net power outputs of 64 b.h.p. at 2,800 r.p.m. and 57 b.h.p. at 2,500 r.p.m., respectively. Its gross and net torque outputs are 143 lb.-ft. and 139 lb.-ft., respectively, the torque peak occurring at 1,400 r.p.m.
The new unit has several components common to the six-cylindered version, including pistons, connecting rods, cylinder liners, injectors, timing gears and bearings. The timing gears are of manganese-molybdenum steel, and twopiece exhaust valves with Austenitic steel heads and free-release rotators are employed. The cylinder liners are of • the slip-fit dry type.
The crankshaft, which has cold-rolled fillets to give added resistance to cracks at stress points, has induction-hardened journals and crankpins, and it runs in five main bearings. These, like the bigend bearings, have replaceable steelbacked copper-lead shells.
A helical-gear-type oil pump provides lubrication and all oil passes through a full-flow replaceable-element filter. Positive feeds to.the valve-operating mechanism and timing gears are provided.
C.A.V. fuel injectors and injection pump are used, the pump having a pneumatic governor. A diaphragm-type lift pump, mounted on the injection pump, is employed. A combined oilbath air cleaner and silencer is carried on the air-intake venturi.
rt134 The engine, complete with clutch but excluding the clutch housing, weighs 785 lb. It adds £131 5s. (including purchase tax) to the price of the 25-cwt. and 35-cwt. chassis, compared with the cost of a petrol-engined model, and £156 55. to the 2-ton and 3-ton chassis.
Typical prices of the new oil-engined vehicles are: 25-cwt. chassis and cab, £718, plus £148 2s. 10d. purchase tax; 2-ton chassis and cab, £800, plus £168 8s. 9d. purchase tax. The reason for the difference in price between the engines for the lighter and heavier models is that an exhauster is fitted to the 2-tonner and 3-tonner engines.
With the announcement that Vauxhall Motors, Ltd., are now building their own two-speed axle, they thus become the first British commercialvehicle manufacturers to make such a unit on a production basis, and further stresses the growing tendency for larger manufacturers to make themselves less dependent on outside component suppliers.
The new axle is available as an optional fitting on all Bedford models of 4-ton capacity and over, except the passenger chassis. It has hypoid-bevel primary gearing and an epicyclic secondary train. When this train is locked up the axle is in high ratio. and for low ratio the sun gear is stopped anti the drive passes through the epicyclic train with corresponding reduction in ratio.
Ratio changes are made by means of a vacuum-servo shift unit, and the control consists of a small button attached to the gear lever adjacent to the knob. This works the change-speed control valve electrically.
The axle has a rated capacity of 17,000 lb.—the same as the standard Bedford single-speed unit—and it weighs only 110 lb. more than the standard axle. T he standard ratios are 5.8 and 7.9 to I, but when used in the 8-ton and 10-ton tractor units ratios of 6.4 and 8.7 to 1 are fitted. It has a basic price of £105 and carries £26 5s. purchase tax.
On the 7-ton chassis this means a saving of £100 compared with the price of the chassis with the Eaton axle.
By introducing moulded brake facings as standard throughout their range, Vauxhall Motors claim to be the first of the mass-production commercialvehicle manufacturers to do so.
No additional price is occasioned by their use and the facings, which have been produced to Vauxhall's own specification and standards, have been designed primarily to give improved anti-fade characteristics. At the same time, compared with woven facings, they are claimed to have a much longer life, to reduce drum wear, and to have a more consistent coefficient, of friction.
A fourth change to the standard range is announced. This concerns the CA 10-12-cwt. van, which does not have moulded facings, but is now being produced with 15-in.-diameter wheels and larger-section tyres, instead of the 16-in. wheels used previously. This has caused a reduction in overall height and loading height of 1 in., and as the ratio of engine speed to road-wheel speed is lower, top gear tractability has improved.
The tyre size with the new wheels is 5.90-15-in. (6-ply), but heavy-duty 6.40-15-in. (6-ply) equipment is offered optionally. Previously, the standard tyre size was 6.00-16-in. (4-ply).
There is no price change when standard tyres are fitted, but when the heavyduty equipment is employed an extra £6 5s. (plus £1 5s. purchase tax) is charged. This is much cheaper than the price previously charged for heavy-duty tyres, the extra formerly being £13 4s., including tax.
Rim embellishers, as used on Vauxhall cars, are now available for use with the 15-in, wheels, being offered at £5 5s. per set of four.