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Overloade( -But Still Game

9th August 1957, Page 42
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Page 42, 9th August 1957 — Overloade( -But Still Game
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New Vauxhall Victor Engine and Gearbox are Latest Improvements to the Well-tried Bedford CAV Van, Giving Good Results

By John F. Moon, A.M.I.R.T.E. SIlSICE its introduction over five , years ago the Bedford CAV van has had numerous minor modifications which have generally improved its overall specification. In March of this year, however, the new Vauxhall Victor engine and gearbox were incorporated in the chassis.

As with the previous power unit, the new engine is an " over-square" design, with a deep skirt to ensure crankcase rigidity. Following current popular American practice, the new engine, by virtue of its short stroke, can run at up to 4,400 nom., at which speed it develops 55 b.h.p. Similarly, the torque characteristics have been improved; the curve is now flatter and the torque output has been increased to 78 lb.-ft., compared with the 71 lb.-ft. output of the former unit.

No Petrol Waste

A new Zenith carburetter used with this unit to improve fuel economy incorporates an adjustable accelerator pump to vary the output during winter or summer conditions, and 'a special float chamber and emulsion block, designed to prevent wastage of petrol when the vehicle is standing on steep gradients and to reduce spillage caused by percolation. • Dimensionally the new unit is similar to the former engine. A 7--in.diameter clutch is retained and takes the drive to the new three-speed allsynchromesh gearbox which is used in the Victor car. •As before, a steering-column gear-change linkage is incorporated, but it is one of the best that I have ever used. Its porAtive a8 action is a welcome change from that of some gear-change mechanisms of this type that I have had to deal with.

The provision of synchromesh on bottom gear cannot be termed a luxury, particularly with a delivery van, and inexperienced drivers will find no difficulty in selecting bottom gear when negotiating heavy traffic in towns.

Apart from minor refinements, the chassis has remained basically unchanged over the years, but the van tested had eight-leaf rear springs (instead of the seven-leaf. units fitted as standard) and 6-ply tyres, these being available as optional equipment. They allow the gross weight to be increased from 33 cwt. to 361cwt. The van was tested with a 2itcwt. overload, despite which its performance was good, particularly. with regard to acceleration and fuel economy. Its hill performance was adequate for most normal conditions, although during the test the overloaded van could not be restarted when stopped on a 1-in-5 gradient.

Light Steering The screw and peg steering formerly fitted has now been replaced by a recirculating-ball gear which makes the steering particularly light,. although this lightness combines with slight oversteer to make it necessary to." drive" the van all the time on the open road.

As supplied for test the van was carrying a payload totalling 14f cwt. 01 this, less than 1 cwt. was being carried by the front wheels. Complete with Vauxhall representative and myself the van was tested at a gross weight of I ton 19 cwt, there being a 10-cwt difference between the frontand rear-axle loadings. Without test equipment and. passenger it should be possible to carry a payload of nearly 15 cwt. without exceeding the recommended gross weight.

Optional equipment fitted to the test van included semaphore direction indicators, fresh-air heater, windscreen washers and a passenger seat which was set back so as not to obstruct access to the driving seat from the near side.

Blind Spot The standard position for the direction indicators is on the wings just ahead of the front wheels and here they. are not readily visible to following traffic. • I think flashing direction indicators on the front and rear panels would have been far more effective.

A single driving mirror is provided as standard equipment, and leaves a large, dangerous blind spot on the near side, which tends to make the driver feel helpless in heavy urban traffic. Cyclists are a particular source of worry.

For the fuel-consumption tests the van was taken out to the A6 road between Luton and Bedford, where a six mile out-and-return circuit between Barton and Clophill was used. This course is undulating in nature, carries a fair amount of traffic and is only of two-lane width, so that the results obtained are repre sentative of those to be expected from operation under average conditions.

Seven consumption runs were made in all; three with full load, three with a half-load and one Unladen. When making the runs which entailed stops, each stop was of 15 seconds duration, during which the engine was left idling.

Normal acceleration rates were used when pulling away from the stops and the resulting average running speeds are high for this type of

operation. Nevertheless, the fuelconsumption rates returned are not unreasonable and the overall picture is that the van, in view of its gross weight as tested, is reasonably economical under all conditions.

Premium-grade petrol was used throughout these tests, because the engine had a 7.8-to-1 compression ratio. An alternative ratio of 6.8 to 1 is offered, this being suitable for use with regular-grade petrols.

covered 360 miles during the test and used 13.6 gal. of fuel, equivalent to an overall consumption rate of 26 m.p.g. . The mileage covered included the acceleration, braking and tests, and a run of over 100 miles which was com pleted at an average speed of 38 m.p.h. when carrying a full load.

A dry asphalt surface was used for the braking tests, despite which all the wheels locked when Making emergency stops from both 20 m.p.h. and 30 m.p.h. The foot brake is particularly effective, however, and when not using full pressure, safe and confident stops, unaccompanied by skidding, can be made under normal conditions.

The hand brake is good. It is placed to the left of the driver and a sharp pull-up immediately locks the rear wheels. When applied from 20 m.p.h. an average Tapley meter reading of 33 per cent. was recorded, showing it to be an effective emergency brake.

Acceleration tests were conducted up to 50 m.p.h. and good times were recorded, the particularly silky action of the synchromesh enabling quick gear changes to be made. Slight pinking was heard during the tests through the gears and during the direct-drive runs.

Top-gear runs were made. from 10 m.p.h. upwards, and up to 15 m.p.h. an understandable amount of engine roughness was noted. Indeed, at 10 m.p.h. it was difficult to keep down the speed of the van, as the engine was running at little more than idling speed.

Direct-drive tests showed a cornmendable consistency of acceleration rate in this ratio, but top-gear performance at speeds below 20 m.p.h. was not particularly invigorating. Drivers would be well advised to use second gear below this speed and thereby save throwing unnecessary stress upon the engine bearings.

Succornbs Hill was used for the hill-climbing and brake-fade tests. It is half a mile long, with an average gradient of 1 in 9 and sections of up to 1 in 4+. The climb was made in an ambient temperature of 65° F. and at the bottom of the hill the coolant temperature was 183° F.

Fast Climbing

Starting from a standstill at the foot, the hill was ascended in 1 minute 24 seconds, during which time bottom gear was engaged for all but 10 seconds, this being on the less-steep section between the two major slopes.

The time recorded is fast for a vehicle of this weight and the speed rarely dropped below 10 m.p.h. The engine was made to work, however, as shown by the fact that the coolant temperature had risen to 195° F. during the climb. Fortunately the system is pressurized:so the cooling arrangements should be adequate for most normal operations in this country and overseas.

A descent was then made in neutral, using the foot brake to restrict the speed to approximately 20 m.p.h. It lasted for I minute 8 seconds, at the end of which time an emergency stop from 20 m.p.h. was made and no fade was recorded, despite the rather pronounced smell of hot brake facings. This test, which is severe, was sufficient to convince me that fade is not likely to be a problem.

Safe Hand Brake

Returning to the 1-in-5 section of the hill, 'which occurs at a railway bridge, the van was stopped and the hand brake held it in perfect safety, although the drums were still hot from the fade test made just previously. A smooth restart could not 132 made, however, and only by violently slipping the clutch was it possible to move the van forward after my passenger had dismounted.

The standard van, however, when carrying a payload not exceeding 12 cwt. would certainly have been able to restart on the 1-in-5 gradient 10 and might even have got away on the 1-in-41 section without a passenger aboard.

Apart from the slight oversteer already mentioned the van handles well on the road and visibility is up to the standard generally associated with a vehicle of this type, but a great improvement would he made by the simple addition of a near-side rear-view mirror, this being available at a cost of only 5s.

Forward visibility is particularly good, it being possible to see Within 9 ft. of the van at ground level, and none of the stumpy " bonnet " is visible from the driving seat.

Engine noise is reasonably low, but a certain amount of vibration is transferred to the body over the whole speed range of the engine, being particularly bad at about 35 m.p.h. in top gear when pulling hard on full throttle. Similarly, slight suspension rumble is transferred to the body from the front wheels, because no rubber bushes are used in the front suspension linkage.

Engine Faults In details the engine is not entirely faultless. Several times during the lest the spring clip holding part of the throttle linkage together came adrift.

Another fault concerns the carburetter. At one stage of the test the acceleration suddenly became bad and I took the vehicle round to my kcal Vauxhall dealer, the Capital Motor Co., Ltd., who recognized the defect as being a sticking acceleratorpump piston. This they quickly put right, having had to do the job before, and I was soon on my way again with acceleration power fully restored.

The standard of the van body is high, for a mass-production vehicle. Little body rattle was heard, access to the driving seat from each side of the vehicle was first-class, the driving position was good, and ventilation more than adequate, particularly when the cab doors were slid back where they are held in position by spring clips.

Door Problem

Spring clips are also provided to hold the rear doors fully open, but they are rather weak and the outer door, when the van is standing on a steep camber, does not remain open. Although slightly more .trouble to use, a manually engaged catch would be more effective, even if on this door alone.

The interior finish of the cab is a little austere, particularly when coin:.

pared with vans of around this capacity which are derived from private cars. The facia panel is plain, there are no sun visors and there is no glove box; but there is provision for small papers in pockets above the windscreen. This is essentially a commercial vehicle, however, and makes no pretence at providing luxury accommodation.

Various maintenance tasks were carried out. The first was to check the water level, the radiator filler cap being accessible upon lifting the hinged flap which lies in the front paneL Checking this level took only 7 seconds, and it was quite easy to see the level of the water in the header tank.

Oil Difficulty Engine oil can be checked by lifting the inner bonnet lid, the dipstick being on the right-hand side of the crankcase. I spent lf minutes on this task, however, because of the difficulty of finding the hole in the crankcase through which to insert the stick. Some simple form of pressed-metal funnel would be of great assistance.

All four parkirig plugs can be reached from the back of the engine and I removed No. 2 plug in 20 seconds and replaced it in a. further 30 seconds. The wire-gauze air cleaner fitted to home-market vans can be detached by removing the clip around the top of the carburetter bell and the clip holding the cleaner to a steady bracket on top of the engine.

It needs 11 minutes to take off the cleaner and 2* minutes to replace it. This job is done from the rear of the engine, as also is the removal of the petrol-pump filter element. This takes 20 seconds, and replacement 25 seconds.

Simple Task •

The battery is located beneath the cab floorboards on the left, and access to it is given by rolling back the mat and removing a springclipped metal panel. Checking the battery levels is a simple matter, therefore, taking only a minute.

The master cylinder is beneath the floorboards on the right and once again the mat has to be rolled back, revealing a round metal plate held in place by two Phillips screws. I spent 1 minute 5 seconds checking the brake-fluid level.

To check the gearbox oil level it is necessary to get beneath the vehicle, there being a square-headed fillerand-level plug on the left of the gearbox. This I removed and replaced in minute 5 seconds, whilst noting that the position of the hole would not make it particularly easy to top up the oil level in the gearbox without the use of a syringe or pressure feed.

A similar plug is provided in the back of the rear axle and the oil level was checked in 50 seconds. Again, replenishment of the level in the axle would not be particularly easy, because the filler orifice is very close to the front of the spare wheel.

The brakes are reasonably easy to adjust and, following the instructions in the driver's handbook, I used the jack provided in the toolkit to raise the vehicle and placed it beneath the frame. side members. The van was fully laden at the time and it took me 31 minutes to jack up a front wheel and 5+ minutes to raise a rear wheel, lowering taking 1 minutes and 41 minutes respectively.

With each wheel jacked up it takes less than a minute to adjust the brakes. There are two adjusters per brake, both being accessible through the wheels and consisting of serrated sleeves which can be prised round by means of a screwdriver. Paddlebox covers over the rear wheels take only 10 seconds to remove and less than 25 seconds to replace.

Complicated Idea

As a final task I removed the spare wheel, which required minutes. This is much longer than would normally be needed but the wheel is secured by a complicated system and the locking nut takes a long time to unscrew. The wheel is reached by raising a hinged flap beneath the body and its removal does not entail disturbing any of the payload.

Replacement of the spare wheel is not easy, either', mainly because of the difficulty of bolding up the carrier, locating the clip and attaching the nut. I am sure that some more simple and effective way of stowing this wheel could be found.

Optional Springs The Bedford CAV 10-12-cwt. van has a basic price of £435 plus £77 18s. 9d: purchase tax in Great Britain. The chassis only has a basic price of £341, plus £77 18s. 9d. purchase tax. Heavy-duty springs and tyres add £11 to the basic price, plus £2 6s. 6d. purchase tax.

It seems a pity that a company with the resources and ingenuity of Vauxhall Motors, who go to great lengths in proving their new products before putting them on the market, should allow minor—but none the less annoying—faults to mar what is otherwise a sound vehicle with an adequate all-round performance.

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