The New Maudslay Five-tonner.
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Full Details of this Model, which was First Shown at Manchester.
AY we, in placing this de scription o f one of the most recent additions to the industrial vehicle world before our readers, yield • to the temptation to add a modernized simile to that oldtime phrase, "Good wine needs no bush" by saying that a good maker needs no introduction. This new model is quite in keeping with this observation, as the illustrations and decription which follow will convey.
Mandalay Engine Constructicn.
The power unit of the machine, which has a load-carrying capacity of five tons, is a four-cylinder engine of 127 mm. bore and stroke respectively, and gives 40 b.h.p. at 1000 r.p.m. The cylinders are cast in pairs and the two castings are. bolted together by a "sandwich flange " extending down the sides of the cylinders for the whole length of the water jacket. This results in a very stable engine and gives all the advantages of the monobloc " type but none of its disadvantages. In addition, a very free passage for water circulation is obtained, which is, of course, most necessary when the thermosyphon system of cooling is employed, as in this ease.
The company's well known patent overhead camshaft is retained, as on all models, its distinctive advantage being the possibility it affords of swinging over the enclosed camshaft, and thus of exposing all the valves, any one of which can be removed within two minutes should occasion arise.
Another equally important point of engine accessibility is that, after the removal of either crankcase door and unbolting the connecting-rod big ends, a piston may be removed for cleaning or examination inside of 20 minutes. One of our small illustrations shows the crankcase doors removed, and discloses the exceptional accessibility of the crankshaft-bearing caps.
Useful Awards.
It may be remembered that the War Office awarded a Dinloma for these features in the 22 days trial of 1907; the Mandalay also obtained the R.A.C. gold medal in open competition during these An illustration (page 584) shows the engine in situ. It may be explained here that the disposition of the magneto, as suggested by the chain drive in the picture, is not customary ; in this instance it is fixed on the clashplatv to suit the demands of a customer placing repeat orders. In the standard position it is fixed alongside the engine in an accessible location, and is driven by a silent chain suitably enclosed. Engine lubrication is by pressure feed and '25 lb. per sq. in. is maintained by the pump. For cooling, an adjustable ball-bearing fan is fitted.
An Interesting Carburetter.
The carburetter which is fitted to this vehicle is extremely interesting and embodies some novel features. The main body takes the form of a cross, the intake being vertical, and the horizontal passage contains a piston throttle ; this governs the amount of air inlet and mixture outlet. The jet is of the horizontal type and is provided with a series of boles over which slides a spring-loaded saddle or coirer, which is operated by the pis ton throttle. On opening the latter, the jet area and air port increase in strict proportion ; therefore a correct mixture is always maintained at all speeds. Another point, the value of which cannot be over-estimated, is that when desired the throttle may be advanced beyond the closed position and so give a large port opening to the atmosphere. The advantages of this are : —no consumption down hills, no slow running while coasting (which is responsible for much of the carbonization troubles of today), and finally the certainty of internal cooling of the engine when most needed. This carburetter is manufactured by the company under the Everest patent.
Clutch and Transmission.
The clutch is of the leather-faced cone type and is :of large diameter. It runs in a very small quantity of castor oil, and when it is engaged the film of oil between the clutch faces is expelled consequently, the "take up" is most smooth and cannot be felt. The male portion is bolted together diametrically, therefore it can be removed very readily for the renewal of the leather when necessary.
' The gearbox is of the ordinary sliding spur type, giving four speeds and reverse ; top speed is direct drive. Power is then transmitted through the usual propeller shaft with the universal joints fore and aft. The rear end of the shaft is free to slide laterally in its splined coupling. Concerning the gear-change mechanism, a distinct feature is the dispensing with the ordinary gate quadrant and incorporating a gate within the hand lever itself, the lever being of the swinging not the sliding type. Another illustration shows this compact and reliable means of speed control.
A Noteworthy Axle.
The front axle is a stamping of I section to the ends of which are fitted centrally-pivoted swivels within the wheel hubs. One of our illustrations shows the wheel hub with the centre pivot ; the "angle" steering lever and ball connection are also quite clear. All the road
wheels are mounted on Hoffmann roller bearings ; in the ease of the rear wheels they are, of course, mounted on the axle ends as the differential shafts are of the floating type. The rear axle is worth particular attention. It is a decidedly robust forging of nickel-chrome steel and is without weld through its length. Swaged out at the centre it houses the double reduction and the differential gearcase. This is a Maudelay patent and is identical with the axles on all their models. One of the photographs which we reproduce gives some idea of the doublereduction housing. The final ratio here is 7.64:1, and the drive is in this instance through bevel and
spur gears. Here again accessibility is a primary feature, for by uncoupling the propeller-shaft rear universal joint, unbolting the rear hub caps and withdrawing the differential shafts about 2 in. (as shown in illustration) the whole of the final drive and differential gear can
be removed as a unit for the bench if necessary, without touching the road wheels or even jacking up the chassis. This should certainly appeal to the owner who, after heavy winter haulage, desires to substitute a higher gear ratio to his axle to suit passenger transport during the summer months.
The rear-wheel brakes are metalto-metal, as is also the brake abaft the gearbox ; all have ample surface and are perfectly balanced.
The Maudslay Torque Rod.
The rear springs are not wholly subjected to driving torque or road shocks, as a unique form of torque rod is anchored immediately over the front half of them. The forward ends and centres of these torque rods are mounted on spherical joints, and suitable heavy coil springs are fitted which take up undue shocks.
In General.
The main frame is of channel section, straight from end to end ; a sub-frame of smaller like section carries the engine and gearbox ; there are no rivets whatever in the whole construction.
The body length for the useful load is la ft. 6 in., the wheelbase 12 ft. 6 in., and the track 5 ft. 6 in. The road wheels are steel castings shod with Polack rubber tires, the sizes of which are : —Fronts, 900 mm. by 140 rum. single ; rears, 1020 min. by 130 ram. twin. The petrol tank is placed under the driver's seat, its capacity being 16 gallons. A large illustration shows a fivetonner just returned from a test run fully loaded. The stout oak boxes on the platform have been specially constructed for the quick displacement of test loads from one lorry to another, each box is weighted up to 10 cwt. With a complete load, 70 ton-miles to the gallon has been frequently attained, and, during a recent test, a five-ton machine, the gross weight of which, with body, load and four passengers, was 8 tons 14 ewt., 8 miles to the gallon was accomplished, i.e., 74 ton-miles.
A machine as here described was exhibited at the recent Manchester Show by Messrs. Leach and Seed, the company's North of England
agents. Prior, however, to its being staged there, several deliveries of its type had been made; others are on the way.