-TRANSPORT EX ERIENCES IN WEST AFRICA.
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-r AST week we were able to give the first portion of .1 Jan article by Mr. E. Meeson, in hick he dealt with many of the conditions under wh ch road transport is operated in British West Afric , including the Gold Coast Colony and Ashanti.
He treated with the types of road, t e vehicles employed by various companies and nati e owners, and the use of different types of trailer.
This second and concluding portion of the article contains much valuable information, a d the author's. own ideas as to what constitutes the b t specification for a lorry to be employed in such work We will now continue with the author's notes.
Speed Control with Native I rivers.
In the writer's opinion, the secret of successful transport, where native drivers are eiiployed, is to have an engine the maximum power of,which is given out at low engine speeds, and in this res ect the Albion lorry seems to be almost ideal; even hen governed down to 1,300 r.p.m. or 1,500 r.p.m. t e power does not seem to be materially decreased. This engine speed gives a road speed of from 16-20 .p.b. according to the back axle gear ratio and is quite fast enough when 3-3i ton § are carried. The Albi n governor is exceptionally strong and foolproof a d cannot be tampered with easily ; neither is it an afterthought, driven by speedometer cable, as some re.
The question of whether the govern° drive should be taken from the engine or gearbox as often been raised and seems to depend entirely CE the type of engine. The trouble with the gearbox drive is that it cannot prevent a driver violently rac ng his engine going up hill, or slowly in low gear on he level, and it is this violent racing that should e prevented. However, the Guy engine in use in the old Coast is of the high-speed type, and to fix a go ernor driven by the engine would rob it of niost of i s power, and every ounce of this is required, as tie lorries are nearly always overloaded.
In countries where the runs made re long, and
drivel's only know one speed—which is full speed—the lorry with good power output at a low engine speed, enabling a governor to be fitted without any serious loss of torque, will outlast the high-speed engine every time. Needless to say, the drivers dislike intensely any form of speed control, and on many lorries the governors are often tampered with, but in doing so the drivers render themselves liable to a fine.
It is safe to say that mest, if not all, of the lorries, except those belonging to the Government, are run overloaded. There are reasons for this, the two most important being; first, in order to compete in price with native-owned lorries large pay, loads must be carried on lorries owned by European firms, as the native has no overhead expenses and does not take into account depreciation or reserve accounts, etc., it also costs him very little in food per day if he wishes to economize; secondly, during the cocoa season such large stocks are often accumulated in the bush that they must be cleared quickly. The Guy lorries, for instance, are supposed to be one-tonners, but they carry regularly two tons net pay load spread over the lorry and trailer, the latter itself weighing 15 cwt. The rates are round about 1s. per ton-mile: Trade Schools for Africans.
The question of really good African mechanics is a difficult one. Some are very good in what might be termed repetition repairs on the same make of lorry, 'but they are generally lost. when something new conies along and initiative is necessary. There are a few exceptions to this rule. As a matter of fact,. these men cannot be said to have had a proper training, but have just picked the work up of their own accord. Plenty can do rough work, but very few have the skill that is so necessary in motor work. However, the Government is now running trade schools for teaching the Africans various trades, and it is hoped .that the result will be to turn out some first-class men.
The class of work performed by motor lorries consists generally of • taking goods up country to the stores of the various trading firms, and, in the season, cocoa back. The native-owned lorries do most of the passenger carrying, as their vehicles are naturally faster than the heavier vehicles, being all of the small American type.
The rule of the road and general traffic regulations are the same as in England, and the Government has prepared coloured posters showing a man driving a car and making various signals with his arm when he wishes to stop, turn, etc. Similar posters have also been brought out showing a policeman giving-the trafficcontrol signals. All driving licences must bear the finger-prints of their owner.
There are several brands of petrol in use, amongst which the V.O.C. Sphinx brand is by far the most popular and sells for approximately 2s. 6d. per gallon. This comes direct from America.
Six-wheeler Possibilities.
As mentioned earlier the rigid-frame six-wheeler may have a good future in West Africa, or any country where roads are soft and there is a limit to the axle load allowed.
It would be a great saving if trailers could be done away with and tile load now carried by the trailer axle could be put on the lorry itself. Tyre wear should also be considerably less.
e n erally speaking, lorries run on
normal s u rfaces, and from the point of view of operating on broken and very rough ground, for 'which this type of vehicle was originally designed, the rigid sixwheeler is hardly necessary, but it does fit in with the Government policy of limiting loads.
The specification of a lorry for overseas work that may be considered as approaching the ideal should, in Pie writer's opinion, include the following :—In the first place it should be remembered that if the lorry is going to be driven as the average native drives it, it will rreceive just about double the rough handling that an ;average European driver would give it. Naturally, a lorry for Colonial work should not require to have half its chassis renewed every year, and it should also be remembered that, generally speaking, it will not have the same care and maintenance that it would at home.
For some reason or other a lorry operating overseas is expected to run for ever without giving it any attention beyond filling up with petrol and oil. It is hard te convince manufacturers of the high pressure at which lorries are expected to function, as, for instance, in the Gold Coast Colony, where for six months of the year they are worked much and but little time is " wasted " on them.
Starting with the engine, this should be four-cylindered and give its power at low speeds; it must be fitted with a governor that will not stick and get out of order, and so designed that it cannot easily be tampered with and can be sealed without undue difficulty. Large bearings are absolutely necessary, and the bigend bearings should have four bolts each. Nothing is so detrimental to an otherwise soundly designed lorry as an engine which has to be driven at practically its maximum speed all the time, as no consideration will be given by the driver to the fact that with nursing it will give him better service. Overhead valves, with their added complication and adjustment, are not recommended, but a detachable cylinder head should
certainly be fitted. Positive lubrication through a drilled crankshaft should be employed, with easily dismounted pump filter and accessible inspection hole for the relief-valve adjustment. The oil indicator should be of the plunger type which can be felt and to which the oil is pumped through tubes of comparatively large diameter. The oil sump should be designed to contain a large quantity of oil, and a thoroughly reliable and visible oil-level gauge should be fitted. Very special attention should be paid to the prevention of oil leaking from joints, etc. Throughout the chassis, where shafts protrude much, as in the gearbox and back axle, oilreturn threads should be cut if possible. High-tension magneto ignition should certainly come into the specification, as battery service stations are the exception and not the rule in the tropics.
Great attention should, of course, be paid to the cooling system, a large and sturdy radiator being absolutely nece ssary, together with strong and wellthought out un o u ntings. Nothing gives a lorry a bad name so quickly as a radiator that develops annoying leaks. Here one thing should be remembered: if a radiator loses water on a long run the driver, if he notices the loss at all, will fill the radiator with anything he can find in the way of liquid, even if it contains. 50 per cent, of mud, and the most serious part of this is that he will not report the matter when he returns, so that those in charge of maintenance can drain and flush out the radiator and fill again with clean water. The Albion tropical radiator is an excellent example of a first-class component and enables the lorry to run for daya under a tropical sun without replenishment, whilst the water never boils; a very stout radiator guard should be part of the standard equipment.
A direct-drive fan would be welcome on any lorry. With a very efficient radiator, large pipes devoid of bends and sufficiently large water jackets in conjunction with a low-speed engine, a pump should hardly be necessary, but the fan should be large and strong and the angle of blades carefully set. Inferior engine bonnets have caused trouble ; these should be of a gauge sufficiently thick to prevent being easily bent, and special attention should be paid to the hinges. It is surprising what feeble bonnet clips some manufacturers fit, and many a lorry goes rattling about minus one or two of these because rivets have pulled through or springs broken.
Such a thing as the starting handle, one would think, would not be liable to give much trouble, but it certainly can be most annoying if not made sufficiently strong; very often the dogs are made of poor metal and insufficiently hardened, and sometimes they are not set in correct position relative to the piston. The bracket of the startifig-handle shaft is often feeble and too short, with the result that the whole handle evabbles about, due-to rapid• wear in'the bearing. All these little things count so much when in a country where there are few really good mechanics.
The single-plate type of dry clutch now being used seems quite satisfactory, and if no adjustment be made to take up the springs, then it must be seen that they are amply strong to stand all kinds of rough treatment. A clutch stop should, of course, be fitted and should be adjustable.
The question whether a three or four-speed gearbox should be employed depends largely on the type of country. If this be reasonably level and distances are long a four-speed box should be fitted, which would allow a higher gear on top, thereby permitting the maximum road speed to be obtained with a slow-engine speed, which is ideal. If, however, the country be very hilly and the roads bad a three-speed box would be more suitable. If possible the three and four-speed boxes should be so designed that they can be interchangeable. Whether the gear lever be placed centrally or at one side does not matter much, but the whole mechanism must be very strong to cope with the " crash " method of gear changing indulged in by the drivers.
Pneumatic tyres should certainly be fitted all_round, unless for any reason they are not required by the customer, and if there be any doubt about the size fit the larger. • A carefully designed and very strong steering gear must be combined with the large pneumatic tyres. This should, naturally, be well geared down. These large tyres often 'cause the front wheels to wobble badly, if one of them hits a pot-hole. Sometimes this can be got over by running the front tyres at a lower pressure. Chassis should be designed so that the steering can be fitted to the right or left without 'upsetting the other component parts.
Four-wheel Brakes.
Four-wheel brakes should be a part of the design, provided they can be made practically foolproof, not so much for rapid braking effect, but simply to prevent the rear wheels from becoming locked when brakes are applied, thereby wearing ounces of rubber off the tyres. The drivers always brake harshly, and it is a common sight to see the tyres skidding some distance upon the application of the brakes. In any case the braking surface should be very generous. The brakes on the rear wheels only should be compensated, and adjustment made easy, but without sacrificing strength. A long, open,-hollow propeller shaft with flexible-disc couplings each end should be avoided, as the discs usually wear too quickly and the heavy shaft then runs out of true, causing a lot of unnecessary vibration. If any type of long propeller shaft be unavoidable, a bearing should certainly be fitted in the centre ; large metal universal joints are best.
Final drive by worm seems to be very suitable, provided the metal and thrust bearings are not skimped. Skimping of metal, which is indulged in by some manufacturers to obtain cheapness, is fatal and has given many an otherwise good lorry a bad name. There are, of course, certain roads on which heavy lorries are not allowed, and a light lorry is the only thing; but for general use it pays (at any rate, the owner) to be generous with the metal down to the smallest bolt. This is specially noticeable in overhauling, as so many parts have to be renewed instead of adjusted..
It is hardly necessary to touch on springs, as it is obvious these must be more than up to their work; but the question of spring anchorage is very important and this should be such that the holding-down bolts will remain tight ; but in some lorries these cannot be kept tight and require tightening after nearly every run. The rear-spring anchorage on the Guy is a splen did example of strength in this respect.
On some lorries the front springs are liable to bounce when the lorry is loaded, and in order to avoid broken springs in this case heavy friction-type shock absorbers should be fitted.
The question of wheel bearings is another important one, and the writer's experience is that the tapered roller type takes a lot of beating when a carefully
designed and strong adjustment and locking _device is incorporated with it. The great feature of these bearings is that, owing to their design, there is a large space for retaining the grease, and wheels fitted with this type of bearing can run very much. longer without attention than, for instance, the floating-bush type.
The silencer is a part which certain manufacturers seem to think can be made of any old bit of tin. It is positively astonishing to see the way this important part falls to pieces and breaks off its mounting on some lorries. There is plenty of space under a lorry chassis for a large, efficient and (what is needed for overseas) an extra-strong silencer and mountings or brackets.
An Air Pump Essential.
Mudguards and mudguard brackets should receive much more attention than they do on some lorries; they are usually of much too thin metal, and the brackets often fail to do their work, and once the brackets and mudguards start to shake about they do not stop as a rule until they fall oft This is not a very good form of advertisement.
An engine or gearbox-driven air pump should be incorporated in the design, and this should be sufficiently powerful to pump a tyre with the full load on the body, as, unless watched, the average driver will not trouble to jack the wheel up "rst. A very good quality rubber tubing is necessary, too. Radiator and petrol-tank Caps should be of the W.D. type as fitted to some lorries; these are really excellent. Filler holes should be of wide diameter and the filters extra large, so that the liquid will pass through quickly, otherwise the drivers will simply take the filters out before filling up. It is needless to say that the crankcase oil-filler should be accessible and of large dimensions, 'with a secure form of cap: The petrol tank in the dash has a lot to recommend it, as it eliminates a_vacuum form of petrol supply to the carburetter as well as a long copper pipe. In any case all pipes and unions must be of very generous size, and the nipples should be brazed instead of soldered on. The cocks must also be larger than the average size.
A Mileage Recorder Desirable.
A mileage recorder, driven from the gearbox, as an integral part of the design is very desirable, but need not necessarily be situated in the dash. The shorter the drive from the gearbox to instrument the better.
The gearbox and back-axle casing must be fitted with large, accessible filler holes at the level decided on by the manufacturers, and the caps must have some form of locking device.
A liberal tool-kit should be supplied and should include a really powerful jack.
The driver's position should be beside the engine, to do away with so much lost space.
The foregoing is not by any means a complete speci fication, but if the engine, transmission and frame are really soundly constructed the special attention to such details as have been mentioned will make a lorry more reliable for overseas work in the hands of more or less incompetent drivers. Simplicity, strength and attention to detail are what is required.
The writer has had trouble with all the parts he has mentioned in post-war lorries and during six years' experience, divided between Turkey, Morocco and West Africa.
It is a great mistake to think that a lorry which performs efficiently at home in the hands of a competent driver will necessarily perform efficiently overseas in the hands of a native driver.
It is well to remember that, even in the Gold Coast Colony alone, many of the African natives and Syrian traders have made a lot of money from cocoa or by other means, of recent years, and a number of them has become owners of cheap and small American lorries. It is a fact that most of these are potential buyers of the larger, more expensive British lorry, and the make that has the best name for reliability is going to get the orders, irrespective, in many cases, of price.