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Pitman's Motorists' Library
"The Book of the Morris Minor 1000 (All models to 1960)" by Staton AbbeyCHAPTER I
FOR THE NEW OWNER
[First Aquaintance] [Performance] [Brakes] [Controls] [Warning Lights] [Clutch] [Running In]
When the first post-war Morris Minor was introduced in 1948, it immediately acquired an enviable reputation as a small, inexpensive family saloon that possessed the sensitive steering and beautiful handling qualities of a thoroughbred sports car. The introduction of an overhead valve engine in 1952 was a welcome improvement on the somewhat unenterprising 918cc side-valve engine fitted to the first models but much of the benefit of the new power unit was offset, from the enthusiast's point of view, by the smaller capacity of the engine (803cc) and the introduction, at the same time, of a lower-geared rear axle and a gearbox with more widely spaced ratios. Not until the Minor 1000 was announced in October, 1956, with a 948cc engine, close-ratio gearbox and 4.55:1 rear axle, were the full potentialities of the car realized. Moreover, the new engine had been the subject of considerable development, including prolonged high-speed tests on German motor roads, during which prototypes had averaged over 60 m.p.h. for 25,000 miles. The Minor 1000, therefore, represents the ideal choice for many enthusiastic drivers - but sooner or later the keen owner will probably be tempted to improve its performance by resorting to a certain amount of tuning and modification, and its comfort and convenience by a judicious selection of accessories, as described in Chapters XI and XII.
On First Acquaintance.
An elementary description of the controls and driving methods is out of place in a book of this type - driving instruction these days is very definitely the province of the expert. Even a fairly experienced driver who is, however, new to the Minor, may welcome some brief notes on its handling characteristics, which will aid in assessing its condition and capabilities. For the beginner, one or two points concerning the functioning of some of the controls and instruments will also be added.
Let us assume, then, that a well-maintained car is the subject of a short road test. If the engine is in good mechanical condition, within a very short distance one becomes impressed by the fact that this willing, lively power unit appears to be virtually "unburstable" - an impression that is borne out by the success of these engines, over the years, when used in highly-tuned form in competition and even in small racing cars. At speeds of around 40-50 m.p.h. the engine should be reasonably quiet. As compared with many other small cars, the Minor is notably free from road noise and drumming, although some resonance from the exhaust is noticeable on the overrun. It should accelerate smoothly in top gear from speeds as low as 10 m.p.h., provided that the throttle pedal is not opened abruptly, and should pull strongly on any main-road hill. Second gear will deal with quite steep hills (say, 1 in 7), first gear being looked on more or less as an emergency ratio — which is as well, perhaps, where the novice is concerned as there is no synchromesh to assist the change from second to bottom gear. It is necessary to double-declutch and to speed the engine up quite briskly when changing into first with the car on the move.
Performance and Fuel Consumption.
The road test should enable a fairly accurate assessment to be made of the mechanical condition of the car. A new owner who is doubtful concerning any points should consult his local Morris dealer, who will, of course, be thoroughly familiar with the particular model and the standards to be expected from it. He will be able to judge, for example, from the liveliness and general feel of the engine, whether a top-overhaul or other attention is needed.
As a general guide, it should be possible, with a saloon in tip-top condition, carrying the driver and one passenger, to reach 30 m.p.h. from a standstill, using first and second gears, in just under 7 seconds, and 50 m.p.h. in under 20 seconds. This entails, of course, "competition" driving methods - quite brutal engagement of the clutch and "snatching" of the gear changes — a treatment which might, perhaps, be unfair to a well-used car. A less drastic test is to time the acceleration in top and third gears. From a steady speed of 10 m.p.h. in top gear it should be possible to reach 30 m.p.h. in about 15 seconds - from 20-40 m.p.h. takes about 16 seconds, and from 30-50 m.p.h. a little under 20 seconds. In third gear, 10-30 m.p.h. should take just under 10 seconds. It must be emphasized, of course, that these figures relate to a new or reconditioned engine which has been properly run-in and which is in a good state of tune. The acceleration of the Traveller will be a little slower, owing to the slightly higher weight of this model.
The maximum speed attainable with a new car is in the neighbourhood of 75 m.p.h. (say, 85 m.p.h. on the speedometer). In normal driving 25-35 m.p.h. represents the maximum in second and 40-60 m.p.h. a usable speed in third, depending on whether or not one is in a hurry.
Fuel consumption is always apt to be the subject of controversy between owners. So much depends on the manner in which the car is driven and the road conditions that it is impossible to quote any hard-and-fast figure. For example, if the car is driven hard by an enthusiast — when it is quite possible to put nearly 45 miles into the hour on average give-and-take routes — a consumption little in excess of 33 m.p.g. can be expected. On the other hand, with normal quiet driving, using a cruising speed of about 45 m.p.h., the consumption should be rather better than 38 m.p.g. Really considerate driving can return a figure of 45 m.p.g.
Brakes.
The brakes on Minors have always been excellent: if really effective retardation is not obtained, without any tendency to pull to one side or to lock one or more wheels prematurely, the braking system should be overhauled as described in Chapter VIII. Even on an old car, there is no reason why the brakes should not be brought up to modern standards.
Controls and Instruments.
A few brief notes on the controls and instruments may help to clear up some of the problems that occasionally confront the novice. As has already been pointed out, it is not proposed to discuss in detail any of the actual driving controls as it would be unwise to encourage the novice to make his first experiments unaccompanied by an experienced driver, even when this is permitted by law.
Choke Control.
The knob marked "C" controls the position of the carburettor jet, which is lowered to give the rich mixture required when starting a cold engine. The term "choke," implying a form of air-strangler valve, is therefore a misnomer in this case but has been established by long usage. The control knob should always be pulled out fully when starting from cold but should be returned as soon as the engine will run without misfiring. It can be locked in any position by rotating it anti- clockwise. If the mixture control is kept in action unnecessarily, fuel consumption will be increased and the excessive quantity of condensed petrol will wash the oil film from the cylinder walls, causing rapid wear and corrosion.
The mixture control should not be used when the engine is hot. It is not unusual, during the summer months, to see a driver repeatedly using the starter in an attempt to get a reluctant engine to fire, with the control pulled out fully. The result is simply to flood the engine with petrol, creating a mixture which is far too rich to ignite. In such a case the remedy is to return the choke control to the off position, hold the throttle pedal fully depressed and to operate the starter until the engine fires. This raises a further point: when starting normally from cold with the choke in use, the throttle pedal should not be depressed. The engine should start and idle at a slightly higlier speed than normal when the mixture control is in use.
Ignition Warning Light.
The right-hand, lower red warning light fulfils two useful functions: it glows as a warning to the driver if the ignition is switched on while the engine is stationary, thus preventing the risk of the battery being accidentally discharged and the ignition ceil being overheated. The warning light is, however, wired into the battery-charging circuit in such a manner that it glows whenever the cut-out points are open. Consequently it should be extinguished whenever the engine is slowly speeded up and the dynamo develops sufficient voltage to begin to charge the battery. If the ignition warning light does not go out whenever the engine is speeded up above idling speed, first make sure that the dynamo driving belt is not slack or broken and then have the charging system checked - otherwise the battery will be quickly exhausted, and (although a starting handle is provided) it may be necessary to obtain a tow or professional assistance to get the car started. It will be seen, therefore, that this little light is a valuable warning device which should not be ignored. If the light does not glow whenever the ignition is first switched on, the bulb should be checked and renewed as described in Chapter VII or the fault in the circuit put right at the earliest possible opportunity.
Oil-pressure Warning Light.
Similarly, the green warning light on the left should glow whenever the ignition is first switched on. If it does not do so, the trouble should be investigated as soon as possible. This light is controlled by an oil-pressure-operated switch, which is adjusted so that if the oil pressure falls below a safe figure the light will glow as a warning to the driver. Obviously this warning should never be ignored - the car should not be driven until the oil level in the sump has been checked and the lubrication system tested by connecting a pressure gauge to the warning light switch union — a job which can be done by a Morris dealer or practically any garage. The pressure shown under normal running conditions should not fall below about 40 lb/sq.in. About 20 lb/sq.in. should be recorded when the engine is idling. Low pressure can be caused by a number of faults, which are dealt with in Chapter III. If the warning light flickers on and off when the car is driven fast around corners the indication is that the oil level in the sump is dangerously low and that the oil is surging away from the intake to the oil pump. This obviously is a danger signal which cannot be ignored. The car should be driven as quietly as possible until the normal sump oil level can be restored.
The Clutch.
The clutch on the Minor has a short travel, giving rather abrupt engagement if the pedal is not released progressively. If judder should develop, check the adjustment of the engine tie-rod (Fig. 8) as described in Chapter II. Some beginners have a habit of driving with the left foot resting on the clutch pedal. This is a bad practice - even light pressure, if applied continuously, will cause unnecessary wear of the clutch release bearing — the bearing that transfers the thrust from the clutch pedal to the clutch release levers — leading to noisy operation and excessive clutch pedal travel. Moderate pressure on the clutch may cause the linings to slip, resulting in overheating and rapid wear.
The same fault will be caused if the clutch is slipped in an attempt to avoid the necessity of changing to a lower gear when the engine is overloaded. Wear on the friction linings will cause the pedal to move further backwards towards the driver and when the free movement is taken up, persistent clutch slip will occur. In such circumstances adjustment to restore free movement, as described in Chapter II, may not cure the slipping. A clutch overhaul, which is a moderately expensive item, will be needed.
Running-in a New Car or Reconditioned Engine.
A new or reconditioned engine, gearbox or rear axle needs to be "run-in" in order to allow the working parts to develop a special type of polished surface which can be obtained only by driving at moderate speeds without the use of full engine power. It is virtually impossible for the manufacturer to produce ideal bearing surfaces by machining procedures alone.
During the running-in process, however, the minute "hills" and "valleys" left by the machine tools are gradually rubbed down. It will be obvious that either excessive speed or heavy loads on the bearings at this stage can result in tearing and local fusion of the microscopic metallic projections instead of a progressive polishing action. The manufacturers of the car recommend that the speed in top gear should not exceed 35 m.p.h. for the first 200 miles - similarly, the speed in third gear should be restricted to about 25 m.p.h., in second gear to not more than 15 m.p.h., and in bottom gear to 10 m.p.h. Even when 500 miles have been covered, however, and the car has received its initial free service, it should still be treated with respect - it is still very new and consideration during the first 1,000 miles will be well repaid by a longer life and sweeter running.
To be honest, the driving speeds just quoted are given only as a general guide for the less experienced owner. Any engineer will tell you that ideal polishing conditions are obtained only by a combination of moderately high rubbing speeds and light pressures. While damage can be done by too high a speed, which causes undue friction and overheating, excessive pressure at low rubbing speeds will also cause heavy friction and a tearing action. One would not attempt to polish household silver by rubbing heavily and slowly - light, brisk polishing gives a much finer finish. As much harm can be done by forcing the engine to labour on a hill at 20 m.p.h. in top gear, as by driving at 60 m.p.h. when the engine is still relatively new. The ideal is to maintain, whenever possible, a small throttle opening. When 500 miles have been covered the maximum speeds in the various gears can be increased progressively a little at a time, provided that the engine is not heavily loaded. It is true to say that the engine will not be entirely free and will not give its best performance until between 2,000 and 3,000 miles have been covered.
Another aspect of running-in is the necessity for adjustments to the engine and chassis. It will be evident that during this initial period the parts will tend to settle down to some extent and the factory-set clearances will be altered. Therefore, after the first 500 miles have been covered, one or two vital points must be checked. On a new car this will, of course, be done by your Morris dealer without charge. If a reconditioned engine has been fitted, however, it may be necessary for the owner to carry out the work, although most garages prefer to make the check themselves.
The contact-breaker points in the distributor will need to be reset to the correct gap since the fibre heel of the contact-breaker arm will have worn slightly and the gap will be reduced. The steel cam which operates this arm imparts a hard, glazed surface to the heel which is resistant to wear so that subsequent adjustments will be required only at much less frequent intervals.
While dealing with the ignition system it is also necessary to check the tightness of the sparking plugs, since air leaks past the washers fitted beneath them can upset carburation and cause loss of power. The cylinder head and manifold nuts will need checking and tightening as described in Chanter III taking care to follow the sequence illustrated in Fig. 9. Over-tightening can damage the threads and distort the head or the manifold flanges.
The tappet clearances will then require adjustment. The slow-running adjustments on the carburettor should be set as described in Chapter V. A rather weaker slow-running mixture can be used when the initial stiffness of the engine has worn off. The friction linings in the clutch and brakes will have bedded-down so that it will be necessary to carry out adjustments to both these items, as described in Chapters II and VIII.
Also, the wheel nuts and the castellated nuts on the rear axle shafts may have bedded-down and should be checked for tightness - this is a safety precaution that should not need stressing. Under-chassis items should be checked-over while the car is on a lift. Finally, the car should be taken on the road and the engine thoroughly warmed up, after which the oil should be drained out, carrying with it any particles of metal that may have been rubbed away from the new parts.
Running-in Compounds.
It is worth mentioning at this point that the use of one of the various proprietary types of running-in compound is an advantage when running in a new or overhauled engine. These compounds contain colloidal graphite or molybdenum disulphide in extremely finely divided form which adheres to the surfaces of the mating parts, forming virtually a chemical bond with them. The action of graphite or "moly" can best be understood by considering the surfaces as they would appear under a microscope. With normal running-in, the minute peaks and valleys are gradually rubbed down until reasonably flat surfaces are obtained. When a running-in compound is added to the oil, however, it is deposited in small flakes or scales, forming a slippery skin which is bonded to the metal and is capable of lubricating a bearing even when oil is not present. It also facilitates the spreading of an oil film.
It will be evident, therefore, that a bearing is not run-in by the usual rubbing down process - the metal is not abraded away. Instead a most interesting process takes place which the metallurgist terms "plastic deformation." The peaks and valleys are levelled out by actual deformation of the metal and a surface layer is formed which is extremely resistant to wear. After the initial running-in period a running-in compound still confers some benefits although its use is by no means essential. In the opinion of the author it is an advantage always to use a small proportion of graphite or molybdenum disulphide — say one-fourth of that recommended for running-in purposes — in order to maintain a protective film on the working parts. One other point should be borne in mind - because of the less drastic action which takes place during running-in when one of these compounds is used, the running-in period may be rather more prolonged than would otherwise be the case. It is as well, therefore, not to over-stress the engine for, say, the first 1,000 miles and to treat it with respect even after this mileage. The result will be an engine which will have a much longer life between overhauls and one which will probably delight the eye of the expert when it is eventually stripped for examination.
Of course any companies or products mentioned in the text may not exist today and any prices listed are of course no longer valid, so take company and product references with a grain of salt.
If anyone has a problem with copyright then please contact me.
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