Page 19 - Demo

Page 19.Alvis Three Litre Shop Manual - T.A. 21 and T.C. 21Frostt Precauti cautionAs the car heater does not drain itself completely when the radiator and engine are drained, it is recommended that a reliable proprietary brand of antifreeze mixture is used in the winter. It is important that the manufacturer%u2019s instructions regarding mixture strength and topping up should be closely followed. Cooliingg SSysttemm Mai ainttenaancceEVERY 250 MILES (400 K.M.) OR WEEKLY. %u2013 Check radiator water level.ENGINE IGNITION SYSTEMBatteryThe efficient functioning of the coil ignition equipment is dependent on the condition of the battery, the maintenance of which is dealt with in the section on Electrical Equipment.Iggniti ition SSwitc witch aand Waarniingg LLigighttWhen the ignition is switched on, the red ignition warning light on the fascia board lights up indicating that current is flowing through the coil windings, and reminding the driver to switch off if the engine is not running. The light should go out when the engine speed is increased showing that the dynamo is charging.Failure of the warning light bulb will not in any way affect the ignition system, but should be replaced as soon as possible to safeguard the battery. The bulb can be replaced quite easily when the bulb holder has been pulled out of its socket at the back of the fascia board.CoilThe coil requires no attention beyond keeping the moulded coil top clean and occasionally checking that the terminal connections are tight.The coil may be tested by removing the coil high tension cable from the distributor and holding it about 1/4%u201d from some metal part of the engine, while the engine is turned over. If sparks jump the gap regularly the coil and low tension wiring is functioning correctly.If not, test the low tension wiring by turning the engine over slowly when a discharge rising and falling with the closing and opening of the contacts should be shown on the ammeter. A spark should be produced at the contacts when they are quickly separated by the fingers with the ignition switched on.If a fault is indicated examine the wiring and check that all contacts are secure. The battery may be dismissed as the cause of the trouble if the lamps will light.DDiisttribut ibutorTo ensure that accurate ignition timing may be obtained the distributor is provided with a micrometer adjustment.If the firing is found to be too early or too late, adjust the knurled knob half a division on the scale at a time, until the best engine performance is obtained. Clockwise rotation advances the ignition. Over-advanced ignition causes %u201cpinking%u201d and rough running, and a retarded spark makes the engine sluggish and produces a heavy exhaust note.Aut utomatic matic Advavancce aand RRetatard MecchaaniismmThe distributor is also fitted with an automatic advance and retard mechanism which automatically alters the ignition timing to suit the engine speed and load.The timing of the ignition spark is advanced, as the engine speed is increased by a centrifugally operated governor housed within the distributor body. As the engine