A FINE NEW RANGE
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OF MORRIS COMMERCIALS
Normal and Forward-control 30-cwt., 2-ton and 3-ion Vehicles of Large Freight Capacity Selling at Competitive Prices, Six-cylindered Engines and " Silentthird" Four-speed Gearboxes
SICE the inception of Commercial Cars; Cars, Ltd., Soho, Birmingham, a go-ahead policy has always been pursued, but never has this progressive characteristic been more in evidence than at the present moment. We are able to announce the introduction of an entirely new range of vehicles, the design of which incorporates several interesting features, whilst prices, are distinctly moderate. The new models are for 30-cwt., 2-ton and 3-ton loads, and each is available with normal and with forward control. Thus there are six new vehicles.
Prices range from 1230 for the 80-cwt. normal-control lorry to 1323 for the 3-ton forward-control lorry, the former model being built on a chassis of 11-ft. 2-in, wheelbase, while the wheelbase of the latter vehicle is 13 ft. 6 ins. The forward-control arrangement might ..really be described as semi-forward control; the engine casing protrudes into the cab and divides the floor into two spaces, one for the driver and the other for the mate. The body sizes and overall dimensions of the whole range are. tabulated below.
One of the features of the new rango is that a high percentage of parts is interchangeable, thereby simplifying standardization when a fleet of vehicles of varying capacity is employed. It follows, therefore, that a general description of the range can be given, for the power units are common and, except for dimensions, the designs of the three sizes of chassis are similar.
In each ease the. frame has sidemembers upswept over the rear axle, and the cross-bracing is reinforced by two angularly placed channels which are carried along the side-members towards the front—a method of construction which gives groat strength at the paost heavily loaded part of the frame.
There are substantial channel-sectioned cross-members between the front and between the rear eyes of the •rear springs, whilst a tie between the angularly placed channels creates a properly triangulated section amidships, so that lozenging and weaving of the frame should iv well-nigh impossible under ordinarily severe road conditions, The chassis has semi-elliptic springs fore and aft, those at the rear (4 ft. 2 ins. long and 2i ins, wide) being equipped with auxiliary leaves to give progressive springing, according to the loaded condition of the vehicle.
We will now consider engine details. Rated at 25.01 h.p., the six cylinders are bored to 82 ram., which, with a piston stroke of 110 mm., gives a. swept volume of 3.485 litres. With quite a moderate compression ratio a steady output of 55 b.h.p. is available.
The cylinders are cast en bloc with the upper half of the cranlicase, the sides of which are extended below the crankshaft centre, and are reinforced with internal webs to carry the main journals. Side-by-side valves are employed, and are operated by a large-diameter hollow camshaft running in four bearings, the whole being lubricated from an oilbath. A duplex roller chain, the tension of which can be regulated by adjusting the dynamo mounting, provides the drive.
A detachable cylinder head is employed, the water; jacketing, being of ample dimensions. Light reciprocating parts tend to reduce the secondary forces ; the pistans, for example, are of aluminium with four rings each, ease hardened gudgeon pins of large diameter being clamped into the connecting-rod small-ends. Steel stampings of light, robust section are used for the connecting rods.
A full pressure lubrication system is provided, the spur gear pump being mounted externally on the near side of the crankcase, where it is driven off the camshaft by a diagonal shaft, the upper half providing the motion for the ignition distributor on the opposite side of the unit. The pump draws oil from the sump and forces it through a large renewable cartridge-type oil filter directly to the main and camshaft bearjugs; the crankpins receive their supply through drilled passages in the crankshaft. The cylinder walls are fed by splash by the surplus oil from the bigends, likewise the gudgeon-pin bearings, whilst the overflow from the camshaft is delivered to the duplex chain drive in the timing case. The sump has a capacity of two gallons.
Cooling is effected by the thermosiphon system, with the assistance of a water impeller located in the cylinder head and driven off the fan spindle. A gilled-tube radiator, having a large water capacity and cooling area, carries a chromium-plated cover of attractive design, the tubes being protected by a wire guard.
Built unit-wise with the engine is a dry, single-plate clutch with the friction linings riveted on each side of the free member. One of the interesting features of this new range is the fact that a four-speed gearbox having a silent third gear is provided. A. cast-iron casing carries short, stiff shafts, Ind in conjunction with accurately cut gears and double-helical pinions for the third B26 speed cluster, the gears run with a commendable degree of silence. It might be mentioned that all the pinions are made of case-hardened nickel steel, and are "paired up" by means of a runningsilence test before being assembled, a further test of each complete gearbox in the silence room being made before installation. The gearbox indirect ratios are 5.987, 3.368 and 1.829 to 1. These ratios are used in conjunction with a rear-axle reduction of 5.714 to 1 in all models except the 3-tonner, which has a reduction of 6.571 to I.
The whole engine-clutch-gearbox unit is three-point mounted on rubber, the front suspension being effected by a rubber-held trunnion, whilst blocks of rubber are employed at each side support, which is taken from an extension of the flywheel casing to a bracket attached to the frame member.
Power is transmitted to a spiral-bevel rear axle by means of a two-piece propeller shaft, the forward end being connected to the gearbox shaft by means of a fabric universal joint ; thence a short solid shaft connects to a self-aligning centre bearing, the housing of which encloses a substantial metal universal joint. Thereafter the driving shaft is enclosed in a torque tube which is spherically mounted at its forward end.
The half-shafts of the rear axle are of the fully floating type, whilst a four star bevel-pinion differential is employed, and the wheel hubs are mounted on tapered-roller bearings.
All of the new models employ the Lockheed hydraulic braking system, the pedal applying expanding shoes within drums attached to all four wheels ; the hand brake lever operates shoes in the rear drums only. Except in the case of the 3-ton model, which has 16-in, rear drums, 14-in, drums are standardized, the friction surfaces being ground to the finished sizes. '
The illustrations give the best indication of the general design of the bodywork and the arrangement of the cabs ; so far as platform-space is concerned the dimensions given in the table speak for themselves. In both forward-control and normal-control types there is plenty of cab room, and the driver's vision all round is good. A safety-glass windscreen is provided in all cases, and the doors are wide enough to allow easy ingress and egress. In the normal. control types the cabs are of all-steel construction, whilst in the forwardcontrol models the framing is in hard wood and the panelling in steel.
It is interesting to note that the unladen weight of the 3-tonner does not exceed 2if tons, so that the vehicle can operate at up to a maximum legal speed of 30 m.p.h. and, at the same time, is taxed at only £28. Good general equipment is provided; the electrical installation includes a five-lamp lighting and starting set, the headlamps having a dippingbeam control on the steering column. Electric direction indicators and an electric horn are included. The instrument panel carries a speedometer driven from the gearbox, oil and petrol gauges, an ammeter and the usual ignition warning light and switch ; furthermore, the prices, given in the table on the preceding page, include a complete spare wheel and tyre.