A HEAVY-DUTY 3-TONNER.
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Details of the Latest Model Republic Chassis, which Embodies Many Unusual Features, including a Laminated Drum for the Transmission Brake, and Final Drive by Internal Gears Running in Oil.
ONE of the best-known and most sueeessful of the American-built vehicles operating in this country is the Republic, which is constructed in various load capacities, and is marketed by Republic Motor Truck Sales and Service, Ltd., 20, Peterborough Road, New King's Road, London, S.W.6.
We have already referred to this chassis from information derived from American sources, but it was only last week that we were able to see an. actual example. This proved to embody many new, interesting and practicable features, and it differs in many respects. from previous types.
Working through from the front, the radiator is of the header-and-bottomtank type with a removable cellular core, but here we find the unusual • feature that the header is of polished cast aluminium, whilst the sides and bottom tank are of cast-iron painted black.
A Continen,tal Red Seal engine of 4k ins. bore and 5i. ins, stroke affords
ample power. It is a four-cylinder monobloc with detachable head, and is cast separately from the crankcase. The centrifugal water-circulating pump and the American Basch magneto are driven in line at the near side, the magneto having both a Vernier coupling and a• flexible disc. Cooling is assisted by a four-bladed fan with steel blades riveted to a centre which is mounted on a swivel bracket and driven by a flat belt. The water pump has two glands, easily ad
justable, and so arranged that no water can enter the crankcase.
Lubrication is 011 the full-pressure system, the oil pump being of the gear type and having an oil-pressure gauge mounted on the dash. Two covers are employed for enclosing the valve-operating mechanism, and provision for lighting and starting is afforded by the fitting of two detachable covers at the back of the timing case. The exhaust and inlet manifolds are cast integral, but on the exterior is a plate or cover which, when removed and rePlaced in the inverted position, reduces or increases the flow of heat to the inlet pipe, according to its position. To assist in the proper positioning of this plate, it it marked " on " and "off."
Carburation is effected by a Stromberg instrument, and the air supply is Passed through a dry centrifugal cleaner provided with two fans. A large and convenient oil filler is provided on the timing case. It has a sliding, springheld pressed-steel cover. An unusual fitting is the Pharos oil governor, which keeps the speed of the vehicle to 15 m.p.h. This works on the principle of utilizing the pressure of the lubricating oil against a diaphragm which controls a butterfly throttle, and the device cannot be tampered with without the knowledge of the owner of the vehicle, and Unless the butterfly be removed altogether.
An excellent feature is that the front cross-member can easily be unbolted from its brackets to permit access to the timing case.
The four-speed Fuller gearbox is bolted up to the crankcase, the easing also enclosing the multiple disc clutch, which has Ferodo and steel friction surfaces. Both the change-speed lever and brake lever are centrally positioned, and the complete unit is three-point suspended in the chassis.
Behind the gearbox is a short shaft with a Spicer joint at the forward end, whilst the rear end is supported in a Skefko self-aligning bearing, and mounted at this end is a very wide brake drum of a most curious pattern, as it is built up from a large number of thin steel segments belted together and somewhat resembling the laminated wood pulley sometimes used for shafting.
It is claimed for this construction that it obviates uneven expansion of the drum due to heating caused by the friction of the shoes, whilst the thin laminations also help to dispense this beat. The ;hoes are external, Feroda-lined, and mounted on an extension bracket of the housing for the bearing of the propeller shaft. The shoes are contracted against compression springs by means of a cam of somewhat curious shape, and the shaft of this cam has three holes, to any one of which the fork of the operating rod can be connected.
To allow even pressure on the shoes, each is centrally fulcrumed in its carrier, and so accessible are the parts that it is claimed that the shoes may be relined within half an hour.
The second portion of the propeller shaft has two Spicer joints, and it leads to an improved type of dual axle known as the Eaton, and built under Torbensen patents. The chief feature of this axle is that all the gears run in oil baths for, unlike the original patterns where the gear rings of the internal drive form part of the rear wheels, in the Eaton they form an integral part of the axle proper and are completely enclosed, so preventing both the loss of oil and the ingress of dirt and water.
The weight-carrying member consists of a double-banjo forging in the centre of which is carried the housing for the spiral bevel gears of the rightangle drive and the differential, whilst behind this load carrier are tubes through which run the differential shafts ending in the spur pinions of the final drive.
Each rear wheel is mounted on its hub flange, so that the wheel can be removed without disturbing any of the bearings.
Brake drums of the usual type are fitted to the rear wheels, and in these operate machine-cast shoes of a strong but light type faced with Ferodo and also cam-operated.
Unusual construction does not end here. It also applies to the Van caststeel wheels, which are built up in four segments, each having two spokes and with the rim segments dovetailed together. These segments are forced into intimate contact by the pressed-on tyre bands, and are also held by bolts near the hub. The front wheels have single tyres of the solid plain type, 36 ins. by 5 ins., whilst at the rear single tyres, 36 ins. by 10 ins., are employed, but in this case they are of the cushion type.
The springs are long and, especially in the case of those at the rear which take the driving and braking stresses, are carried on very out brackets on the frame side-membNa.. The back spring hangers are Y-shaped, each arm of the Y being riveted to the frame, both on the web and the flange, and the hangers are connected by a stout tie-rod, separate shackle bolts being employed. A semicircular, pressed-steel cross-.member of unusual strength is interposed between the front brackets of the rear springs, these brackets being riveted through the frame side-members to this cross-member.
Gwilliam taper roller bearings are used in the wheels.
The Jacox worm and split ,nut steering gear is irreversible and adjustable, and steering is facilitated by the 18-in. handwheel. Leather gaiters are fitted to the ball joints of the drag link, whilst the cross rod has fork-and-pin joints.
The frame has a depth of 7 ins. It is perfectly straight, and the dumb-irons are separate castings riveted into the channels.
Other points of minor importance are the silencer, which, instead of being a single casing, is built up from a number of rings; link-type compnasators for the hand brake ; swivelling plates for the control pedals, and leather mud flaps on the front wings.
Throughout the chassis the lubricators are of the Dot grease-gun type ; each nipple has a three-start thread, and the gun is secured to it without intermediate tubing.
Compared with the average ,3-tonner, the frame level is low, due to the use of springs which are almost flat. In spits of its sturdy construction, the weight is only 2 tons. The wheelbase is 13 ft. 9 ins., the track 5 ft., and the turn ing circle 30 ft. The price of this chassis is 1595.