Useful Hints.

Progress, Volume II, Issue 3, 2 January 1907, Page 101

Useful Hints.

A Mysterious Squeaking Noise. Sometimes a motor will develop a mysterious squeak when running, and this often takes a deal of locating. Many motors are fitted with the wipe type of contact-maker, and it is well to look to the wiper blade and the disc on which it rubs for the source of the squeak. If the disc is allowed to get dry, a most distressing noise is caused by the rubbing of the steel wiper piece on the fibre of the disc or by the bearing of the roller on the wiper arm when the latter is rotated. A spot or two of ordinary lubricating oil will effectually cure the trouble.

Fitting Sparking Plugs. Though all sparking plugs are theoretically of a standard size as to that part which screws into the cylinder, there would appear to be some difference of opinion between makers as to the internal diameter of the sparking plug hole in the cylinder. This has been brought home to us in this wise : We were out for a short run a few days ago, when the engine commenced to misfire, undoubtedly from plug troubles. Having a new set of plugs awaiting an opportunity for testing, we decided to fit the new set, but, to our surprise, found that the plugs could not be induced to enter the cylinders. The old plugs were replaced, the faulty ones having been cleaned and adjusied. The next day we proceeded to investigate the why and wherefore of the new plugs not fitting, but found they entered the cylinders quite easily when the engine was cold. There is no difficulty in accounting for this, but it incidentally shows why some manufacturers wisely make the sparking pluck orifices of larger diameter than the corresponding screw threads on the plugs. Very often in new sparking plugs the thread is burred where the earth wire is let m. The burr should be removed with a triangular file.

Battery Troubles. When an accumulator has been standing idle for any length of time, although it may show four volts, and even slightly over, when tested by a voltmeter, it is not safe to assume that it will work in a reliable manner when desired for ignition purposes to run a motor. The voltage of an accumulator may appear to be fairly high after a rest, and yet immediately a small amount of current, such as is used by an induction coil, is required from it, the

voltage diops down from below 38, and this is insufficient to work an ordinary ignition coil With such a battery the engine will start up readily enough, and will run for a matter of twenty seconds or so, then the engine speed will gradually decrease, and ultimately the engine will stop. After a few moments' rest the engine can be again started, with similar results. The novice is rather inclined to think that this shows that the battery is in good working condition, and that the trouble lies with the petrol supply. The symptoms, however, are different, for with an insufficient petrol supply, m addition to slowing up and stopping of the motor,

there is also always a back .f'ring in the carburetter when the petrol supply is insufficient. The best way to keep accumulators which are not used regularly is to give them a freshening up about once a week or fortnight by connecting on to a charging dynamo. When treated in this manner very little charging current is required, and the batteries are always kept in excellent working condition, free from sulphating of the plates, and can always be relied upon for use when required.

Repairing Radiators. Leaky radiators are not a common complaint, but as they do occasionally occur, as we know to our sorrow, the recital of the means wi> adopted to overcome a badly-strained tubular rae iator will be of interest. It was but a few days igo that we started for the scene of a competitH n which we desired to witness. The route took as over some exceedingly lumpy by-roads, which, despite good springing, had such a vibratory effect on the radiator, that no less than six of the vertical tubes became loose in the lower tank to such an extent that the water flowed freely from them. The first intimation of trouble was overheating of the engine and steaming at the radiator filling cap. As we were approaching a small town, and could run down hill thereto with the clutch out, we did so before making investigation. Having pulled up at a convenient place, and made everything right for a good inspection, we got out of the car and took a preliminary walk round, arriving in front of the car, to find the radiator fast emptying itself from unexpected sources. There was nothing for it but to dram the tank, which we did. Then, drying oft the water from the tubes, we procured a canful of water from a neighbouring hostel, and filled up again until we had located the faulty tubes by watching the water run from the fractures, which all occurred at the soldered joints of the lower tank. Time and circumstances did not permit of our having the joints re-soldered, so we procured some white lead from an ironmonger, and smearirg this on small pieces of rag. laid them round the fractures, previously dried and cleaned, binding each tube round with string, so as to force the coated rag downward on to the tank. When each tube had been so treated, the radiator was filled up with water to test the joints, which were found satisfactory, and packing was introduced at suitable points to brace up the radiator. The journey was continued, and between thirty and forty miles traversed without the loss of more than half a teacupful of the cooling fluid.