HINTS THAT HELP

Hawke's Bay Tribune, Volume XX, Issue 269, 1 November 1930, Page 13

HINTS THAT HELP

A PLUG TESTING HINT. Many motorists are under the impression that there is no means of testing the spark at the terminal oi the sparking plug without receiving a shook, unless a screwdriver, hammet - or other tool with an insulated handle be used. An all-metal spanner can be use<J just as well if care be taken to put one end of it in contact with the clylinder block first, subsequently bringing the spanner nearer the terminal until a gap sufficiently email for the spark to Jump is obtained. When removing the spanner or other tool, care should be taken not to lift the earthed end until the other part is sufficiently far from the terminal to avoid all risk of contact.

DETERMINING ENGINE SPEED. Instructions for adjusting carburetters for idling, and other operations, frequently specify an engine speed of perhaps 300 revolutions a minute, but in the absence of a revolution counter it is frequently difficult to judge with accuracy, particularly with a very quiet exhaust. Where valve tappets are accessible, it is easy to judge low speed accu-/ rately by placing a finger on any tappet and counting the number of times it is lifted during 12 seconds. This figure, multiplied by 10. gives the engine speed in revolution a minute. CARBURETTER ADJUSTING. Almost any kind of carburetter adjustment will cause the engine to run idle, but a more careful adjustment is necessary to obtain pulling qualities. Make sure that spark control meets the conditions desired when adjustments are being made. With a retarded spark one van hardly expect any power from the engine. First make sure that the engine has good compression and then see that a good spark, both in retard and advance position, is obtained. After this the carburetter should be adjusted to obtain a good mixture. With these three fundamentals, namely, good compression, good ignition and good mixture, no trouble should be experienced in making the engine pull. CUTS IN THE TYRES. Apart from the usual routine of testing the tyre pressures, it is advisable periodically to examine each cover for any cuts or damage to the walls; moreover, all flints which may have mecome embedded in the rubber should be dug out, a screwdriver oi similar tool being used for the job. Do not employ a sharp tool, as this may pierce the. cover and tube. Flints, if ignored, may be forced through the cover and cause a puncture. A BONNET CATCH. Meccano parts are often very useful to the motorist for making email clips, etc. A neat catch for holding the bonnet when open is made by° cutting a slot in the beading currying the anti-rattling tape with a hacksaw; two angle-pieces of Meccano are screwed to the dash, and a small nut and bolt passed through the bottom hole of the small strip, long enough to extend up through the slot. Tho small strip should project sufficiently far above the bonnet flange to prevent the bonnet falling. A simple holder for a festoon bulb can be made by screwing two anglepieces to an insulated base, just so far apart that a festoon bulb can be held by the two holes. The ends of the wires connected to it should be bared and placed under the screws, a couple of small washers being used. » « « CURES FOR PETROL LEAKS. As petrol is by no means a cheap commodity, it is just as well to stop all leaks that may take place. It often occuis that tho plugs situated just beneath the jets on some types of carburetters become wet, due to a slight leakage past the fibre washers. These plugs should be removed, and the washers given a coat of shellac or other oilproof jointing liquid. Petrol pipe unions are other parts that frequently develop slight leaks. The remedy is to unscrew them and coat tho contact surfaces with jointing liquid. Where a gronnd-in-union has been badly damaged, the best thing to do is to cut a narrow ring out of thin lead or fibre sheet. The ring should go on to the conical part of the union, and, when screwed up. will make a tight joint. It is not generally known that the well-known brands of metal polishes are good mediums for grinding-in plug taps or needle valves.