Newcomer Sets High Standard
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German-built 15-cwt. Van has Four-wheel Independent Suspension and Rear-mounted Air-cooled Engine : A Cab Heater and Other Refinements are Provided
by Laurence J. Cotton, M.I.R.T.E.
THERE are few power units, for light cornmercial vehicles, that can compare with the efficient operation of the Volkswagen four-cylindered horizontally opposed petrol
engine. In its entirety, the 15-cwt. van is remarkable both in construction and performance, as I found during a series of tests, totalling over 200 miles in one day. Much can be said for the driving comfort in that I felt far from weary at the end of the run.
Having previously driven a Volks
wagen in Germany, its liveliness with light load was not surprising, but trying the van with a 15-cwt. payload on home ground confirmed that it is speedy and economical, and well equipped, in its lowest ratio, to soar over the 1-in-41 gradient of Succombs Hill with power to spare.
In physical layout it is similar to the Volkswagen car, having the compact, four-stroke, overhead-valve petrol engine housed in a compartment at the rear. It is air cooled by a fan and a constant temperature is maintained by a thermostat which
also passes a regulated flow of air over an oil cooler. No difficulties were encountered in cold-start tests after the van had been left out overnight on a parking ground during a period when several degrees of frost were recorded.
The engine is reached by lifting a
hinged panel at the back of the body. In this compartment there are also the 6-v. battery, 81-ga1. petrol tank and spare wheel, the latter being
housed on a shelf above the power unit. Accessibility to the dynamo, coil, distributor, carburetter and petrol pump, is excellent, which is to be expected with the small, flat engine being housed longitudinally in a compartment which is as wide as the body.
As my tests started before daybreak, I appreciated the built-in illumination of the engine bay when connecting the petrol lift pump to an auxiliary supply. This small attention to detail is found in many other parts of the van.
The clutch and four-speed synchromesh gearbox are attached to the front of the engine and the final drive is through a spiral-bevel gear to swinging half axles, and then through a secondary spur reduction gear in the hubs. The Volkswagen power and transmission units are thus compactly grouped and arranged for easy change or major repair. The engine, of 1.192-litres capacity, and a compression ratio of 6.2 to 1, develops 30 b.h.p. at 3,400 r.p.m.
Like the car, the commercial version, which is available as a van, eight-seater bus, ambulance and as a combination of a bus and van, is of semi-integral construction having a basic structure for all models but differing in the assembly of the upper sections.
The commercial versions are all forward-control types with the front axle situated directly below the fullwidth driving seat. Considering the 8-ft. wheelbase is about the same as many local-delivery electric vehicles, the suspension of the Volkswagen 13 extraordinarily good.
The independent front suspension units employ trailing links on laminated square-section torsion bars and the independent units at the divided rear axle have round-section torsion bars. Double-acting hydraulic shock absorbers are fitted at all wheels.
Good Suspension Although tested with varying payloads up to 17 cwt. maximum. I found nothing to criticize in the springing, and even deliberate driving over a 4-in. kerbstone at 15 m.p.h. failed to " bottom " the buffers.
The wide cab doors, hinged at the front, give good access to the driving seat, but the gear and hand-brake levers projecting through the floor obstructthe driver so that he cannot get out on the near side without some difficulty. There is a speedometermilometer which is the only instrument provided, the head lamp beam, traffic indicators, dynamo charging and oil pressure being indicated by lights on the facia panel.
No fuel gauge is provided, but the tank has a three-way tap affording a one-gallon reserve after the main supply is used. Although austere, the instrument-panel equipment is adequate for a van.
Built-in Heater
With the engine at the back of the body, the cab would be cold in winter without some form of heating. A built-in heater, therefore, forms standard equipment, hot air from the engine being suitably ducted to the cab.
This I found to be most effective within a few minutes of starting the engine, and the only possible fault that could be visualized is that fumes that are prone to emanate from an engine that has seen considerable service might also be forced into the cab. As it is, Volkswagen has provided an effective unit without additional cost.
The cab furnishing is severe, a compressed paper-board lining being used to window level, and, as already indicated, the instrumentation costs little. It is surprising, therefore, to
find swivelling glass vents and sliding windows in the doors, twin windscreen wipers, and cab and interior lights in the body forming standard equipment.
The low engine position does not prevent rear doors being fitted to the van body, but on the model tested there was a 3-ft. 10-in.-wide opening with two doors at the near side and similar doors can be provided at the off side as an optional extra. For a 15-cwt. van the payload space of 141 cu. ft. in the main section of the body, plus another 21 Cuft. over the engine bay, might invite overloading. The loading height, when unladen is 1 ft. 7 in
After taking delivery of the van from V.W. Motors, Ltd., in London, I loaded 15-cwt. of ballast in the body and drove through the busiest part of the city to the suburbs. The engine idled and ran smoothly, but, like other Volkswagen models I have driven, could not always be guaranteed not to stall when pulling up sharply in traffic.
Although its acceleration, with load, could not equal that of the fast newspaper delivery vehicles, the van put pp a spirited performance and with reduced payload it kept its place at the head of all other traffic.
Apart from being easy to control in steering and general handling, the gear change was without fault and rapid movements of the lever evoked no protest from the box. It is preferable to pass through all four gears for the best acceleration with full load. On a quiet level stretch of road alongside the Thames I found the acceleration rate to be from rest to 30 m.p.h., 13.2 sec., and to 40 m.p.h., 22.7 sec.
No Wheel Locking
The maximum effort on the pedal failed to lock the wheels during braking, which is unusual for a vehicle of the light-van class. The Volkswagen has hydraulic braking which, when carrying full load, will stop the van in 43 ft., from 30 m.p.h., which corresponds to 0.7g. The excellent distribution of load, 18i cwt. on the rear axle and 18 cwt. at the front, may have been contributory to the prevention of wheel locking although the brake frictional area corresponds to 81 sq. in per ton with this load.
Before starting consumption trials from Godstone, I tried the Volkswagen on Succombs Hill to verify the maker's claim that the van will climb a 1 in 4.3 gradient with full load. This it did without faltering, but I could not stage a stop-start trial on the 1 in 41 gradient without abusing the clutch. With an 8 cwt. payload, however, the result was quite successful. The van made no fuss when starting from rest on a 1 in 5 gradient with a 15-cwt. load and a passenger. It was well geared or general work.
Extensive fuel consumptiontrials o9 were made, embracing varying degrees of load and making oneand four-stops-per-mile tests in addition to continuous running. The result of these trials is shown in the accompanying table, the speed for the oneand four-stops-per-mile tests being developed from the time the wheels were turning.
By running these trials early in the morning there were no traffic difficulties, and between 5.30 a.m. and 10 a.m. 18 runs were made with corn
parable conditions and reasonably equal average speeds. From the results it is apparent that the maker's claim for a consumption rate of 30 m.p.g, is not unreasonable at a steady speed with load. The course chosen was slightly undulating.
As I did not spare the engine or brakes during the local-service trials, the return of 19.1 m.p.g. carrying full load and stopping every mile is an economical figure. It is upon the results of these trials that I acclaim the Volkswagen engine to be above average in its efficiency. It is especially good for local deliveries because of its rapid " warm up " from cold, no engine heat being lost in a water-cooling jacket.
After 200 miles arduous work there was no increase in pedaltravel, neither could the brake adjusters be taken up without.binding the wheels. If competition is measured by the performance of the Volkswagen the standard is high.