Trying out a Light Van from Cowley
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The Morris 5cwt. Van Shows the Beneficial Results of a High Power-to-weight Ratio. Marked Fuel Economy a Feature IN the issue of The Commercial Motor dated September 2nd we described the two Morris light vans for 1931; the larger has a payload of 8 cwt. whilst the smaller will carry 5 cwt. It is the latter vehicle which forms the subject of the present test report. The chassis employed for this van is the popular Morris Minor, having a four-cylindered overhead-valve engine driving through a unit-mounted threespeed gearbox to a spiral-bevel rear axle, the torque and drive of which are taken through the springs.
A I4e* Standard Vehicle.
On arrival at the work g of Morris Motors, Ltd., Cowley, Oxford, we found that the van for trial was a brand-new one which, according to the speedometer, had covered only. 11 miles. The vehicle was standard in every way; the body—a Morris product—was duly laden with metal weights evenly distributed over the floor space. In addition our representative was counted as part of the load of 5 cwt.; normally, of
c26 course, the van would carry only the driver.
To check the weights the van Was driven on to a finely calibrated scale in the export packing department. The gross weight, including the driver and observer, was 19 cwt. 12 lb. After removing the dead load the personnel left the scale and the unladen vehicle then recorded 32 cwt. 1 qr. 12 lb. The difference was, therefore, 6 cwt. 3 qrs.; after subtraction of the driver's weight it was found that the pay-load was a few pounds in excess of 5 cwt. This burden was, of course, maintained throughout the entire test.
Care was taken in stowage of the load to avoid rattles when travelling. As a result we were able to listen for chassis or body noises without interference. Although the engine reaches 3,600 r.p.m. at the peak of the power curve, there was no sign. of vibration at any point in the range and there was no noise from the propeller shaft.
Naturally, the absence of mechanical noise ruled out a common cause of sympathetic drumming but our test route was capable of causing a lot of body distortion. That no sound. either squeak, groan or drumming, came from the body shows that it was \'ell built. No part of the load or equipment touched the body sides or roof, so that normal conditions prevailed.
While on the topic of bodywork the useful capacity is .38 cubic ft. Theinterior height is 3 ft. 6 ins., the width 3 ft. 41 ins, and the length behind the driving seat 3 ft. 4 ins. The wheelbase of the vehicle is 6 ft. 6 ins, and the track 3 ft. 6 ins.
Main-road Running.
Before undertaking any of the usual specific. tests we covered a fair mileage on main roads in order to bed down the brake facings and to run-in the engine somewhat. For commercial work it is most important to allow a good margin for engine cooling. To test this we covered a long ascent on full throttle in second gear with a following wind; the distance travelled thus was 1.6 mile and the water in the header tank was tested immediately the van came to rest. The thermometer registered 198° F. As the engine was new and, at the time, the brakes were not quite free, it is obvious that boiling need not be feared in everyday work.
During the early part of the run the speedometer was checked ; the error was found to be just under 2 per cent.; for all practical purposes this may be regarded as
Turning off the main roads and running on country lanes, the suspension came in for special attention. All four semi-elliptic springs are damped by separate mechanisms and there are rebound leaves above the main ones. The springs were sufficiently supple to absorb minor shocks and the dampers prevented excessive rebound after occasions of maximum spring deflection. On bends there was no tendency to roll. The clipped rebound leaves played no small part in the prevention of "
bucking" when starting from rest on steep gradients.
Stop-and-restart Tests.
In this connection we carried out stop-and-restart trials on a hill of 1 in 6, three separate stops being made ; the surface was rough and
loose. Naturally, a high engine speed was necessary to effect a getaway, but the clutch was fully up to its work. The hand-operated parking brake was not sufficient to hold the laden vehicle without
"creeping." Continued use of it might effect an improvement. The foot brake was amply powerful.
Retardation trials were carried out on level stretches of first-class main road, the surface being a tarred one of the smooth variely. Only the footbrake was employed. The results are most easily gathered in terms of feet and seconds from one of the accompanying graphs.
That the brakes were correctly adjusted was evidenced by the absence of tendency to pull to one side or the other when coming to rest, even when the steering wheel was being left alone. The brake. pedal travel was convenient and the effort required well within the capabilities of any person of legal age to drive.
Acceleration tests, again, are best studied by means of two of the accompanying graphs. The beneficial results of a high power-to-weight ratio are easily seen. The gear change was both light and speedy, requiring no particular knack. The highest speeds attained on the indirect gears were 20 m.p.h. and 34 m.p.h. On direct drive the vehicle ran from 6 m.p.h. to 51 m.p.h. Actually, the latter figure was exceeded, but with adventitious aid ; we prefer to quote the more coeservative figure as being more representative of normal conditions.
Marked Fuel Economy.
For vehicles of the delivery-van class we have adopted the principle of recording fuel consumption under conditions akin to those of service in the hands of a tradesman. Straight, long-distance running is very rarely likely to be encountered. To arrive at the desired state of affairs the van was brought to rest once per mile and the engine stopped. It was restarted by means of the electric motor and the vehicle promptly accelerated up to a normal cruising speed of about 30 m.p.h. To ensure accuracy a separate fuel tank was employed ; quantities of 1 pint were poured into it and then the van was driven until the fuel was exhausted. The result of the trials on normal roads was the very creditable figure of 46.4 m.p.g. Amplifications of this figure will be found in the accompanying paneL The 5.11. carburetter used was the standard product ; in addition to the accelerator pedal there are two Controls for it. One is a hand control for the idling speed and the other a mixture-strength regulator. The former was left in the position which was found best for the slowest idling which prevented the risk of engine stoppage.
The mixture control was not touched throughout the ' fuel-consumption test ; it was pulled out as far as possible, i.e., in the " weak " position. All other tests were carried • out with the particular control thus set, so that there was no alteration of any detail which might favour good consumption. The mixture regulator is used generally as an aid to running during the first few moments after a start from cold.
Ample room is allowed for the driver and all controls and instruments are well within reach. Although the van carried two men instead of one there was plenty of elbow-room. A detail improvement would be the slight cranking backwards of the gear level to give more clearance for the knuckles between the lever knob and the speedometer bezel when the lever is in either reverse or second-gear position. Triplex glass is used for the screen and windows the last-named are of the sliding type, whilst the screen is of the single-panel variety and can be adjusted to various positions. The tools are carried in a well in the floor to the left of the driving seat, whilst a well also is used to give additional legroom for the driver. There are two doors at the front, so that the driver can dismount without having to open a door across the traffic stream. The spare wheel is carried on a dummy hub on the off-side door.
During the trial we did not carry out any adjustment, but we checked the brake settings. The four-wheel brakes have independent adjustment points in addition to a master one; the hand brake has a turn-buckle on the short operating rod.