This blog, in addition to the usual maintenance details for classic mini cars, an attempt is made to explain the "whys" and "wherefores" of the various jobs.

Sunday, 18 October 2009

Jacking the Car

Three different types of jack are used on the range of models. First, there is the screw-type, which fits into a socket approxi¬mately at the mid-point of the body sill, allowing each side of the car to be lifted with the front and rear wheels clear of the ground. Some of the earlier jacks caused alarm and despondency by buckling as soon as a load was placed on them but the sturdier replacements should not give trouble, provided that the jacking bar is inserted fully into the bracket. If this is not done the jack will be damaged and the bracket distorted.

If the sealing plug has been lost, it may be necessary to clear any accumulation of mud or grit from the socket to allow the projection on the jack to be pushed fully home. Fit a new plug at the first opportunity. If water is found on the floor of the car after driving in wet weather, make sure that one of the rubber plugs is not missing. The water can find its way into the hollow body sill and from there into the car.

The jack should lean outwards slightly at the top to allow for the tilting of the car as it is raised. To allow the central screw to be turned by the wheel-brace, it will be necessary to leave the door of the car open, which can be decidedly unpleasant for passengers in cold or wet weather. More-over the open door can, on occasion, constitute a very real traffic risk. These drawbacks may prompt some owners to carry a conventional screw-type or hydraulic jack which can be applied beneath the normal jacking point.

Never be tempted to jack at any other point, owing to the risk of damaging a body member or the underframe. Also, the situation does arise sometimes in which the desired wheel fails to leave the ground when the jack is fully extended. This calls for some redistribution of the weight in the car which will, of course, tend to pivot around the central jacking point!

Two other tips: make sure that the handbrake is fully applied and that the car is on firm, level ground. If the wheel that is to be removed is next to the kerb, make sure that there will be sufficient space to allow it to be drawn off its studs when it has been jacked-up.

When a ratchet jack is provided, a levelling bracket must be fitted to the pad on the jack, before jacking up the front wheels. The flanges of the bracket must be uppermost and its slot located over the tongue of the pad.

Picture: The compact engine, transmission and front suspension assembly of the standard-transmission Mini

1. Brake drum

2. Steering swivel

3. Upper suspension arm

4. Suspension unit

5. Clutch operating lever

6. Starter solenoid switch

7. Heater water tap

8. Oil filler cap

9. Ignition coil

10. Vacuum ignition-control vapour trap

11. Radiator filler cap

12. Cooling fan

13. Dynamo or generator

14. Fan and dynamo driving belt

15. Radiator drain tap

16. Universal joint

17. Lower suspension arm

18. Transmission casing (engine sump) drain plug

19. Starter motor

20. Oil filter

Place the jack under the front crossmember on the side on which the wheel is to be lifted, as close as possible to the front flange. When a rear wheel is to be raised, the levelling bracket is not needed. Instead, the tongue of the jack must be engaged with the socket on the rear face of- the crossmember.

The third form of jack is the type in which the jacking arm is pivoted on a strut and is moved forward by turning a ratchet handle. First raise the head of the jack until it is in contact with the front or rear crossmember, on the side on which the wheel is to be raised, with the tongue of the jacking pad behind the front crossmember or engaged with the socket provided on the rear face of the rear crossmember, as the case may be. The pad can be raised quickly into position by rotating the milled nut on the end of the jacking screw. Fit the ratchet handle with the word "Raise" outwards and operate it to lift the wheel. To lower the wheel, take off the ratchet handle and reverse it so that the word "Lower" faces outwards.

Fig. 1. How it all began. An early Mini undergoing extensive tyre tests with the Dunlop test team. The operator is measuring the temperature of the front tyre treads after a spell of fast driving

It has been the experience of car manufacturers that a large proportion of drivers in the "family car" class neither require nor appreciate a full set of instruments. Consequently, on the less-expensive models the instruments have been reduced to two essentials, the speedometer and the fuel gauge. A green warning light ensures that any failure of the engine lubrication system will not be overlooked, and a red warning light similarly draws attention to failure of the dynamo to charge the battery and also reminds a forgetful owner not to leave the ignition switched on when the engine is not running. The functions of both these important warning lights will be discussed in more detail later. An owner who likes to have a more comprehensive set of instruments will be interested in the special instrument panels obtainable from accessory shops or the neat Smith's instrument sub-panel which can be mounted beneath the lower edge of the facia panel and which will carry two instruments from the Smith's 2-in. range: for example an oil-pressuregauge, water-temperature gauge, an ammeter; or one of these gauges paired with a dual gauge (oil-pressure and water-temperature, for example) thus giving three additional gauges. Provision is also made on the panel for an electric cigarette lighter.Ignition and Charging Warning Light. The red warning light incorporated in the speedometer dial should glow as soon as the ignition is switched on and when the engine is idling but should fade out when the dynamo begins to charge as the engine is speeded-up. If it continues to glow at normal running speeds, check for a slack or broken dynamo driving belt, especially if the light comes on suddenly during a spell of fast driving. As the belt also drives the fan and water pump, the sudden lighting-up of the warning lamp can enable one to spot the trouble before overheating occurs.