A JAPANESE LIGHT CAR

A JAPANESE LIGHT CAR

THE car is a four-wheeled three-seater, with folding canvas hood and peg-in sidescreens. The power unit is an air-cooled V-twin engine, with clutch and gearbox built in as a unit, driving a conventional rear axle, front-wheel drive being provided in addition. Suspension is independent in front, and by normal semi-elliptic springs at the rear.

As souvenir-hunters had been at work prior to the car’s acquisition, the only data plate discovered was one on the dashboard, and the information derived from it is as follows—though no sort of responsibility is assumed for the translation :—Model, black medal ; year of manufacture, 1941; maximum speed 76 kilos. per hour ; petrol consumption, 56 kilos. per gallon.

So far no road test has been possible, as a suitable magneto has yet to be unearthed, but a diligent search is being made in garages and dumps in Bengal, and it is hoped that this rather vital component will be forthcoming ; apart from the magneto, the only other item of any importance which is missing is the petrol pump, but this will not preclude the car being run as soon as the ignition problem has been solved.

Details of the specification follow ; these are believed accurate, but it is confessed that the dimensions given have been measured with a no more sensitive instrument than a boxwood desk ruler!

Chassis.—Dimensions are as follows : wheelbase 6 ft. 61 in., track 3 ft. 11 in., height (to top of windscreen) 5 ft. 2 in., minimum ground clearance (immediately below the steering bell-crank on the front differential easing) 81 in. The frame consists of a main and a subframe, on which the body is mounted. The main frame comprises two parallel members of channel section, 41-in, deep, very close together (101 in. inside measurement), giving a sort of backbone to the car. Between the front differential casing and the cross-member to which are attached the forward shackles of the rear springs, the channel section members are boxed, the inner faces being liberally pierced. Forward of the front differential casing and aft of the rear spring anchorage, the frame members taper to a depth of 21 in. at their extremities. There are five cross-members, as under :

(1) Front differential housing.

(2) An inverted U-shaped tubular member, from which the power unit is suspended at the front ; the feet of this member are mounted on the outriggers supporting the i.f.s. wish-bones, the body sub-frame also being attached here at its front end.

(3) The gearbox trunnion mounting.

(4) A box-section member, extending beyond the sides of the main frame, to form an outrigged mounting for the front anchorage of the rear springs, and to which is attached the rear ends of the body sub-frame.

(5) A channel section member, extended as above, giving an outrigged mounting for the rear-spring shackles. Additionally, the extremities of the main frame members are joined by tubular bumper bars. Further possible stiffening may be given by the fixed

Some technical details of Japan’s idea of a military runabout.

sheet-metal floor which fills in the space between the body sub-frame and the main members.

Engine.—The engine is a 450 air-cooled V-twin, built in unit with the clutch and gearbox. Liberal use has been made of aluminium in the construction, the sump, crankcase, clutch housing and gearbox casing all being made of this. From appearances, the capacity should be about 1,200 c.c., though this is naturally only surmise ; the cylinder heads have not yet been removed to enable measurements to be taken.

There are two valves per cylinder, with double springs ; they are mounted in the head at 900, and are operated by pushrods and rockers, the whole of the valve mechanism being fully enclosed and pressure lubricated. Valve clearances are adjusted by a slotted-head screw with a locknut, bearing directly on to the head of the valve-stem. The cylinders and heads are heavily tinned, as are also the rocker-boxes ; a throw-back appears in the form of primer taps, which are fitted at the ” rear ” of the heads, the single sparking plugs being centrally mounted between the puslarods in the ” front ” of the engine. Lubrication is on the dry-sump system ; a heavily finned sump (aluminium) is bolted directly on to the face of the crankcase, and is fitted with a fillerbreather and a dipstick ; the capacity is about a gallon. The duplex oil-pump, providing for both delivery and scavenge, is bolted to the front face of the sump, and is driven by an extension of the crankshaft, to which it is keyed. The crankshaft then extends further to

accommodate a fan-belt pulley and starting-handle dog. A small, and very crude, four-Waded pressed tin fan is fitted, hung from the front engine bearer. The dynamo, though missing, would appear to be driven from the fan-belt, there being a vacant mounting on the off side consistent with this.

The power unit is suspended in a manner reminiscent of the early days of Chrysler “Floating Power “—the front mounting being very high, level with the rocker-boxes, while the rear mounting is at the gearbox, which is attached to the narrow main frame by trunnions. All these mountings employ rubber bushes. At the front, an inverted tubular Ushaped member is used, its ” feet ” attached to the anchorages of the front suspension wishbones and the sub-frame. From this the engine is slung by a forked steel plate, sandwiched between the crankcase and the sump.

The carburetter appears to be a Japanese replica of that fitted to the Indian motor-cycle, the appearance being identical, although Japanese characters (undecipherable) are embodied in the casting ; a primitive form of air-cleaner is fitted. The controls are normal, by right-hand, treadle-type accelerator pedal, with the now customary push-pull throttle and choke controls centrally on the dashboard. Ignition is provided by a magneto (missing, literally) and one 18-nun. plug per cylinder. The magneto is mounted on a cast platform low down on the near side of the crankcase, and is driven by the timing gears through a train of gears ; additionally, incorporated in that for the magneto, is a mounting for a petrol pump, from which it appears it is gear-driven off the magneto pinion. The petrol tank is at the rear, with a high filler cap on either side, as in the Nuffield-Riley (whereat all similarity ceases 1), while on the engine

side of the dash is a two-way tap providing a reserve supply.

The starter is mounted on the clutch bell-housing, and extends rearwards to a point level with the gear-lever turret.

Transmission.—The clutch is fully enclosed, and appears to be of the singleplate type ; aft of this is the three-speed and reverse non-synchro gearbox. The central ball-change gear-lever has orthodox positions, and is sprung towards the left or first and reverse gear side. The transfer case is mounted immediately below the gearbox, giving a central drive to the front differential ; control is by a lever mounted on the right side of the gearbox. Drive to the rear axle is taken by an open prop.-shaft with a telescopic splined joint at the front end, with cruciform-type universal joints at each end. The splined joints are provided with a grease nipple (these are all hexagonal Tecalemit type, incidentally), but there seems to be no provision for lubricating the universal joints. A contracting transmission brake is fitted immediately behind the gearbox, and is naturally hand-operated.

Front-wheel drive is taken care of by a similar open prop.-shaft, jointed in the same way as the rear one. From the forward differential, the drive is transmitted to the wheels by open shafts with cruciform universal joints at each end ; it is noteworthy that these are not of the constant-velocity type, splines looking after alterations in track under the influence of the suspension. Omission of constant-velocity joints may possibly point to the four-wheel drive being only intended for very brief periods of emergency use. The rear axle is of conventional, if antiquated, design, rather on the lines of British light cars of the early ‘twenties ;

there is no banjo-form of construction, and the axle is hung from the springs, and not underslung. It would appear to be of the semi-floating type.

Suspension.—Independent front suspension • is employed, with normal semielliptic at the rear. In front, each wheel swings on an upper and lower wishbone, of H-section, with a single coil spring on each side—reminding one faintly of the Buick. Very small piston shockabsorbers are fitted all round, those at the front being mounted on the sub-frame, while the rear ones are mounted only very slightly outboard of the differential housing direct on to the narrow main frame members—a position which would appear to minimise their effectiveness.

The rear semi-elliptics are mounted very close to the wheels, and are anchored at each end to cross-members produced to form outriggers. Oil-less bushes are employed for the shackles.

Brakes.—Apart from the transmission brake, it is a case of rear wheels only. These are foot-operated, separate brake rods extending rearwards to each brake camshaft from the cross-tube to which the pedal is coupled. This layout appears odd, in view of the attempt at modernity shown in the i.f.s. and four-wheel drive.

Steering.—Worm and sector, with the steering box bolted to the sub-frame ; a drag-link goes forward to a bell-crank mounted jeep fashion on the front differential housing. This bell-crank operates a divided track-rod behind the front transmission. The linkage appears to be very sturdy, with large self-adjusting ball-joints and massive tubular connections; the steering wheel is at the right, with three spokes and a central horn button. Wheels and Tyres.—Magna-type steel disc wheels are fitted, with holes pierced

for access to the tyre valves. The tyres, size 6.00 in. by 18 in., have the following moulded on the outside walls : Bridgestone balloon. Heavy duty. Made in Japan. Inflate to 36 lbs.

Body and Incidentals.—The body is a 8-seater, clover-leaf type, of pressed metal construction, with very high sides. A folding canvas hood and peg-in sidescreens are provided—the latter are missing, however. The windscreen framework is integral with the body panels, with heavy fixed pillars at the side and in the centre ; there are two quadrant-controlled opening panels. The screen is very slightly V’d, and the top rails are wired for two electric wipers. The two front seats are of the tip-up variety, with a space of 14 in. between them, in which runs the tunnel enclosing the main frame members ; the central rear seat is rather higher, with side arm-rests mounted on the twin 6-volt battery boxes. The upholstery and trimming generally is a very inferior leather cloth. The dashboard has a door-closed cubby-hole on the left, with the carburetter controls in the centre ; on the right is a panel containing ammeter, oil pressure gauge, trip speedometer, electric petrol gauge and Yale-type ignition lock; The starter switch is missing. Instruments are calibrated with Arabic figures, but words like “charge,” “discharge,” ” empty ” and ” full ” are in Jap characters. The bonnet is of the alligator type, with an easily removable falsegrille in front, in the modern style ; engine accessibility is good, as the side panels and grille are removed very quickly. There are no running boards, while another incidental point is the provision of towing-hooks fore and aft. Finally, for devotees of le Sport, a grabhandle, believe it or not, is fitted to the dashboard.