INCREASED EFFICIENCY

Sun (Auckland), Volume II, Issue 426, 7 August 1928, Page 6

INCREASED EFFICIENCY

GOOD JOINTS ARE IMPORTANT In the jointing of motor engines are points which the owner-driver should know and which, if properly appreciated, may conduce to increased efficiency. It is one of the many details worthy of attention by the owner-driver who desires to obtain the most out of his engine. Take first the matter of flanges in connections such as those between the carburetter and the uptake pipe, the j manifold or the cylinder jacket face, or the joints between the induction manifold and the engine. These are now generally fitted with copper and asbestos washers, but sometimes a thick brown paper washer or a thin copper washer is preferable. When copper and asbestos washers are not available, brown paper is an excellent substitute, and they may be made gastight by facing them with red lead or with gold size. If the surfaces of both the flange and the face to which it is to be bolted are quite flat, so that both bed together and touch all over their surface, it is not a very difficult job to make a tight joint with a very thin packing such as thin brown paper. If the faces are irregular they should be faced up with a smooth file offering them on to each other with a smearing of red lead and oil on one face to see if it leaves the red mark all over the other. If they can be so faced that they touch all over, it may only be necessary, for the purpose of making an air or gastight joint, to smear them with red lead and oil, or with gold size, and bolt them together. This is a better job if it can be done than using any kind of packing. But generally packing is necessary, and it should be as thin as possible, consistent with effecting a tight, close joint. In some cases it is inadvisable to take the carburetter or the induction pipe completely down to make a surface, and then it may be best to scrape the surfaces and to use a packing of a good thickness. The packing washer should be an exact fit as regards the holes for the studs which hold the flange up and the ceneral hole representing the bore of the pipe. This is most important. The central hole should be exactly the size of the bore of the pipe, and should exactly register with it; and the holes of the studs should be located so that they locate the central hole accurately, because, when the washer is in position, one cannot see whether its edge projects into the bore of the pipe.

In making the holes, ttie best way is to use the flange as a template, and even as the actual cutting gauge, by pasting on the gasket material and cutting it out by tapping with a round paned hammer.

The completed washer may be placed in position on the flange before the latter is fitted into position bv seccotine or gold size. Seccotine will ensure an airtight joint, while it will allow of the joint being taken apart without any injury to' the washer, if occasion should arise for dismantling.

In place of seccotine, use gold size. The latter should have a little time to get “tacky” before making the joint. If the surfaces are not quite smooth it may be as well to use red lead and gold size, which makes a thicker cement and fills spaces which the paper alone would possibly not till. The gold size and red lead should be carefully mixed with a palette knife on a flat surface, making sure that no lumps or gritty pieces are left in the lead, but that all is smoothed out to a very smooth paste. The same procedure which is used in the case of pipe flanges can be used for making a joint between an overhead valve engine head and the cover which encloses it. Brown paper and gold size is good for this joint, and the washer may be made by tapping with a hammer on the paper laid on the flange just in the same way as for the pipe flange. The same applies to joints between cylinder bottom flanges and the top of the crankcase, to front drive covers; to pump attachments; and to valve gear covers; and also to the covers of gear-boxes and back axles.

The use of belts in the mechanical details and mechanism of the car is not so general to-day as it was some years ago. Still, we have use for belts, and for some purposes they are the most suitable means of transmitting rotary movement from one part to another. There are all kinds of belts for all kinds of purposes. Thus we have belts for driving speedometer shafts, belts for fans, and sometimes belts for dynamos. Belts will give good service if they are properly designed and run on pulleys Hvhich are suitable for them, and if their tension is correct. A good point about belts is that they need little attention, and no lubrication, while if properly fitted they are, for all practical purposes, noiseless.