TWO NEW SIX-CYLINDER CHASSIS:
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Particulars of the Models JF and JBF Brockway, Designed for 16-seater Coaches and Fast 30-cwt. Delivery Vehicles.
CHASSIS bearing the name of Brockway are by no means new to this country. Those in service have already proved their reliability as fast passenger vehicles, and they are being used to a considerable extent on longdiatance coach route's. They are produced at an American factory which is devoted entirely to the manufacture of commercial vehicles, and they embody certain refinements which should commend them to many buyers. The model JF chassis, which is the one with which we shall deal chiefly, has a wheelbase of 11 ft. 4i ins., and is priced at £395. The model JBF has a wheelbase of 12 ft. 6 ins, and has certain other improvements, including a full-floating rear axle, heavier frame and stronger springs, the price of this being £445.
The sole concessionaires for Great Britain and Ireland for these chassis are Messrs. A. E. Tapper and Co., 100, PalmerstonRoad, High Road, Kilburn, London, N.W.6.
The model JF is designed for 16seater coaches or 30-cwt. goods vehicles of the high-speed class. It has a perfectly straight channel-section, pressed steel frame with channel steel crossmembers, that carrying the brake gear being well stayed to the side-members. Rivets are used throughout.
Careful attention has been given to the suspension. The springs at the rear have a length of 4 ft. 10 whilst those at the front are 2 ft. 10 ins. long. The back springs pre provided with five supplementary leaves to carry overloads and to make the springs more supple when lightly laden, whilst, in addition, each has two 14-in. Ilexdee shock-absorbing leaves clipped to. the top of the main leaf, one at each side of the Ubolts clamping the spring to the axle. They perform the function of pressing the spring leaves together, thus-increasing the friction and damping out oseilla s. A similar method is employed f damping the front springs, but, in this case, the special leaves are in one piece for each spring.
Power is provided by a Wisconsin six-cylindered engine with the cylinders cast en bloc with the upper half of the
crankcase and tile sparking plugs in the off-side of the detachable head. The valves are overhead and operated through the medium of long tappets and rocker arms which are lubricated by oil under pressure, the rockers being drilled for their whole length. The bore and stroke are n ins. and 41 ins. respectively. Four main bearings are provided for the crankshaft.
The vent from the crankcase leads through the cylinder block into the rocker-arm casing and then connects by a pipe with the air intake of the carburetter, thus providing oil mist for upper-cylinder lubrication ; the remainder of the air passes through an air-maze filter and the supply can be adjusted for winter or summer service. Warming of the mixture is effected by a hot spot formed by casting the inlet manifold with that for the exhaust ; incidentally, the exhaust pipe is at the front of the engine.
Purification of the lubrication oil Is
ensured by an filtrator. This is
cleaned in a simple manner by removing a plug at the base and attaching a tyre pump to a valve at the top.
Carburation is effected by an American Zenith instrument. The combined fan and water pump are of somewhat unnival construction. The pump is of the full centrifugal type and not the
usual impeller pattern. For adjustment of the round, rubber-and-canvas fan belt, the whole pump and the fan can be swung on • a centre which is formed by the water outlet fromthe radiator and the inlet to the cylinder jacket. The actual adjustment is effected by a stud at the top of the timing case, and, after adjustment, a nut on the water connection locks the casting in its position.
"Ignition is effected by an Auto-lite coil and distributor set, but provision is made for fitting a magneto if this be desired. An Auto-lite self-starter is also provided and a Northeaster electric horn forms part of the equipment.
Cooling is effected by a honeycomb radiator with a . nickel-plated shell of prepossessing appearance.
The clutch is enclosed as part of the engine-gearbox unit. It is a BrownLipe of the dry, multi-plate pattern. The gearbox is of the same make, providing three speeds and a reverse.
Immediately behind the gearbox is a transmission parking-brake of the external-hand type. A ball-change lever and a brake lever with a quadrant arc carried direct on the gearbox. A power take-off is provided for driving equipment such as £1. tyre •pump and the speedometer drive is also direct from the gearbox. The propeller shaft is a one-piece, swaged tube equipped with Spicer universal joints. A finaldrive ratio of 5 to 1 is provided by the spiral gearing in the Wisconsin axle. the casing of which is drop-forged steel, with a vertical-banjo centre. This axle is of the semi-floating type in the .117 model, but, as mentioned •previonsly, full-floating in the model JBF. Timken bearings are used throughput both.
Chassis lubrication is by bayonettype Tecalemit-Zerk nipples.
The brakes are pailicularly good. They act on all four wheels, the rear " drums being 16 ins, in diameter, whilst those at the front measure 131 ins. The front brakes have an interesting and Practicable form of adjustment by wedge pieces which expand the shoes at the sides opposite to the operating cams; this method prevents the friction material from wearing unevenly. "
A strong channel-steel fender is mounted on the front dumbirons, to which are also secured the cast headlamp brackets joined by a bar to pre' vent vibration. Pressed-steel running hoards join the front and rear mudguards.
Steering is effected by a gear of the Ross cam-and-lever pattern, which is one of the most successful of American components.
The wheels are spoked and of cast steel, with detachable rims, equipped with 32 in. by 6 in. single pneumatic tyres. A spare rim is slung under the rear of the frame.
Dimensions, additional to those already given are: track, 4 ft. 10 ins.; inside of scuttle dash to end of frame, 12 ft. 3 ins. ; frame width, 2 ft. 10 ins.