OODS AND Bus CHASSIS W ITH the advent of the Scottish
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Motor Show, the Albion Motor Car Co., Ltd., Scotstoun, Glasgow, asks us to announce that it is placing on the market two new models. One of these, a new 32passenger chassis, is similar in general layout to the PMA28 model (also a forward-control 32-passenger type), but incorporates an engine of longer stroke developing much more power, the object being to produce a full-size 32-seater-bus chassis for city work, having the advantage of simple layout, the company finding a distinct demand for the powerful four-cylinder chassis. The 32-passenger model is named Valkyrie.
The other new chassis is a two-tanner of entirely new type for its class, but following generally on the lines of the popular Albion 30-cwt. model.
Dealing first with the 32-seater, this has a frame arched at front and rear in normal fashion, and providing a wheelbase of 16 ft. 3 ins., and, within its overall length of 25 ft, a length from back of cab to end of frame of 20 ft. 24 ins., The rear overhang being 6 ft. 11 ins. The frame top, laden, is 2 ft. Oi in: high, the frame width being 2 ft. 81 ins., and the section of the longitudinals 9 ins. by 21 ins. by -ik in. There are five tubular and two girder-type crossmembers in the frame of the Valkyrie.
The ergine is separate from the gearbox, and is 'supported at the front end fiy a forged I-section cross member passing through the crankcase and. having a trunnion bearing, as on the PMA28 model. The rear
n32 engine-bearer is another I-sectioned forging, with palms resting on the frame top.
The bore and stroke of the Your cylinders are ins. and 51 ins. respectively, the capacity being 306.9 cubic ins., or 5.03 litres. With an R.A.C. rating of 29.8 h.p., the development is enhanced by sound
combustion-chamber and general design, the •
compression ratio being given by the maker as 4.89 to 1.
The single cylinder-block casting has detachable dry liners and detachable exhaust-valve inserts. The aluminium upper half of the crankcase carries the main bearings, and the cast-iron cylinder heads are in two pairs. The engine, dry, weighs 790 lb., this including the flywheel. The dry single-plate clutch has an outer diameter of 15-1ins., and three-toggle operation: The arrangement of the chitch stop is shown in: an accompanying
illustration. The four-speed gearbox gives indirect ratios of 1.79, 3.09and 5.07 forward, and, 7.19 reverse. The selector mechanism. is remote from the gearbox, thegate change being provided at the driver's right hand with transmission by three rods.
A two-piece open propeller shaft conveys the drive to the rear axle, and incorporates three all-metal universal joints and a roller self-aligning steady bearing. The final drive is by undersiung worm with a ratio of 6.25 to 1, the axle casing being a triangulated nickel
chrome-steel forging. • The axle shafts are fully floating, the wheels being equipped with 38-in. by 7-in. tyres (twin rear tyres)-, although they are suitable alternatively for 38-in, by tyres. The suspension is very sturdy, the front springs .being 3 ft. 6 ins, and the rear springs 5 ft. in length. They are of semi-elliptic pattern shackled, at their rear ends, and the driving-axle springs are underslung. These take the torque and thrust, With Dewandre vacuum assistance, the pedal operates brakes on the front and rear wheels; the hand-lever controlling a brake on the transmission shaft.. The effective diameters and widths of the drums are as follow : Rear, 19, ins. by 3 ins.; front, 17 ins.
by 2 ; transmission; 13 ins. by 5 ins.; the aggregate friction area thus obtained, being 396.5 sq. ins.
Steering Ls of the worm-and-sector type, the box being mounted well forward and the connecting rod lying back from the drop arm to the steering arm.
It affords a turning circle within the 60-ft. limit.
An excellent feature is the grouped chassis lubrication, practically every conceivable bearing surface being supplied in this way.
Turning now to the two-tonner, it is pleasing to see incorporated so many features of the successful 30cwt. model. The chassis has a straight frame, the tops of the main members being parallel and horizontal. The wheelbase is 12 ft. 6 ins., and the overall length 19 ft. 7 ins., the frame overhang being 4 ft. 11 ins. This pro" vides a measurement from back of cab to end of frame of just 12 ft. The frame width is 2 ft. 6+1 ins., the rear track between the twin tyres being 5 ft. 03 in.
The frame top, laden, is 2 ft, 3 ins. high, anti, the main frame members have a maximum section of 7 ins. by 2 ins. by 7-32 in. There are four tubular and two pressedsteel cross-members, t h o engine-gearbox unit being suspended with trunnion mounting at front and twoeoint mounting at rear.
The engine is a four-cylindered sidevalve unit with a bore of 33 ins and a stroke of 5 ins., the capacity • being 192.5 cubic ins., or 3.15 litres. With an R.A.C. rating of 19.6 h.p., it develops about 24 b.h.p. at 1,000 r.p.m., 42 h.h.p. at 2,000 r.p.m., and a peak of 44 b.h.p. at 2,500 r.p.m., the compression ratio being 5 to 1.
The cylinder block forms a single casting with the upper half of the crankcase, and carries dry liners and exhaust-valve inserts. The lower half of the crankcase and the clutch pit form a separate casting in aluminium, there being a detachable sump plate. There is a single cast-iron cylinder head, and a clever provision is that two of the holding' down nuts are elongated and laterally drilled to take lifting bolts and links, one balancing the engine alone and the other balancing box unit.
A Zenith vertical-type carburetter is employed, and a feature of the induction system is the Ricardo-type split inlet manifold in conjunction with inlet valves which are masked all around to a depth of 116in.
Part of the exhaust gases are by-passed to a jacket around the centre of the induction manifOlcl, and led thence by a pipe of considerable length, which joins the main exhaust pipe not far short of the silencer, at a point where, of course, the gas pressure is suf , B34 flciently low to ensure that the circulation is excellent.
There is pressure lubrication to all main and big' end bearings, with an adjustable relief valve spilling a large quantity of oil per minute over the auxiliarydrive mechanism. The engine weight, with flywheel, but without clutch, water or oil, is 620 lb.
, The clutch is a single dry-plate unit, with an outer effective diameter of 123 ins., the clutch stop taking the form of a brass pad which contacts with the rear face of the constant-mesh layshaft wheel. The clutch spigot runs in a Hyatt bearing. The gearbox, Which is bolted to the clutchpit face, provides four forward speeds and reverse, all the gear wheels being of case-hardened and ground nickel-chrome steel with straight-cut teeth. The ball-type gear change is centrally disposed.
The transmission is by tubular open 'cardan shaft in two pieces, and incorporates three fabric universal joints and a self-aligning roller centre bearing. Final drive is by overhead worm, the ratio being 6.75 to 1, whilst the indirect ratios are 11.9, 20.0 and 31.3 forward, and 26.6 reverse. This is with 32-in. by 6-in. tyres (twins rear), although 36-in. by 8-in. tyres (single rear) are also suitable. The axle shafts are fully floating.
Semi-elliptic springs are fitted, those at the front being 3 ft.
3 ins., and those at the rear 4 ft. 6 ins. long. The rear springs are mounted above the axle by means of a cast chair which takes the braking torque, and, of course, the springs take the torque and thrust. Brake equipment is of the four-wheel Dewandre vacuum non-compensating type, incorpoiating an accessible master adjustment by hand wheel. One pair of shoes is fitted in each drum, the common drum diameter being 17 ins., and the shoe widtha 11 in. (front) and 21 ins. (rear). A hand-lever controls separate shoes in the rear drums, these being 11 in. wide. A total brake friction area of 336 sq. ins, is obtained. The 133gallon fuel tank is mounted on the dash. Steering is similar to that employed on the 32-seater, and gives a turning circle of about 45 ft.
Both the new models have been produced and are now offered to the public as the result of prolonged experimental work and exhaustive trials. The Albion Motor Car Co., Ltd., always exercises the greatest care to add to its range models which, apart from the reputation for quality of material and workmanship which they must share with existing models, meet the real needs of users. Such are the two latest additions.