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Show CHECKING NOISE in rati cars Silence Is a Golden Feature of Modern Automobile Construction. Practical Hints on Best Methods to Secure Maximum Max-imum Quietness, JVe have all settled down to tho long crind of bringing things back, to normal nor-mal after the war, making up our minds to doing without many things Hint, we would like to have, among them that new motor cor on which perhaps wo had pet our mind. And, after all, wo shall not be so badly off if wo take due precautions pre-cautions to keep our cars in first-elans order all tho time, - As time goes en wo are bound to have more or less trouble with noises developing bot h in engine and chassis. These can bo eliminated or, at any rate, minimized, but tome suggestions along theso linos certainly wiil not be out of ' order, Naturally, the greater number of the noises that may develop iu, tho motor car have their location in the engine, because that has b.v far the biggest number of 'parts. Of .all tho engine noiees valve clicks and slaps firo by far the most frequent in occurrence. Fortunately For-tunately valve noises -are easily distinguished distin-guished because of the regularity of 1 heir recurrence. The 1 rouble may bo caused by too much Vrcarahc'o "between the tappet and stem or to tho, same condition con-dition between lifter and stem in the overhead valve mechanism. The cure is obvious, but the owner must be careful to make adjustments in the valve system sys-tem while the engine is hot, because changes made when the metal is cold will not hold true when the engine warms up,- owing to the tendency of metal to expand under heat. By making mak-ing the clearance just perceptible when t hp ongine is hot, any noise will be eliminated. ' Adjusting Valves. Occasionally it wil be found that instead in-stead of the tappet the lifter is at fault 1 hrough wear. The cure hora is ro-rooval ro-rooval of the lifter mechanism and replacement, re-placement, though in some instances the guide mav be sprung a little to hold the A lifter tiphter. Wear of either the cam or follower will produce a slight clicking click-ing and r new follower is the proper course to take in this case. Worn valve stems or stem guides also produce ft noisp. and the course to follow is to ro-rnovc ro-rnovc tho springs anil tost each valve in turn. Hold the stem in the fingers and try to move it sideways in its guide. K ' Ihore is any play perceptible a bushing should be placed in the guide or a valve ty.with oversize stems should be employed. On occasinu it may bo found that a va 1 v c head has warped, and this will cause m slap, and the only remedy is a new valve. The valve heads should always al-ways be examined for warping when the system is being adjusted or cared for. The overhead valve system is apt to be a little more noisy than the conventional conven-tional type, because of the larger number num-ber nf joints. Careful attention to lubrication lu-brication of the system and its adjustment, adjust-ment, will prevent undue noise, f-'ome-1 imes side play develops in the Toe.ker arms with an attendant slap. A bearing bear-ing in the arm may wear. A new part or bushing for the old one "'ilt cure, this (rouble. In case wear in the shaft on whicl the arm moves develops, an oversize over-size bushing in the rocker arm J3 indicated. indi-cated. Bearing- Knocks. While the valve system is the most consistent offender, other parts of the engine develop noisy opera t ion. The bearings may wc.t so that a knock develops, de-velops, growing louder as the wear increases, in-creases, until finally it sounds like the blow of a hammer ou a block of wood. The cure for Ibis condition is. of course, the taking up of the bearings by removal re-moval of the shim between the two halves or the shaving off of the metal on the moalde half. The operation of taking un bearings must be carefully performed or the trouble will be worse instead of better. The new car owner will do well to watch the operation of taking up bearincs before he tries to perforin it himself. When tho piston or the cylinder i f-self f-self is worn much out of round, a knock will result that sounds not unlike that induced bv preigni tion. The reason is simply that the piston, instead of being 1ij;hfly held, has room to ship- The cure is drastic, rebnriiur of the cylinders and . the installation of a new set of ovor-IffN ovor-IffN sbe pistons, ami it should always be the set and not merely a single one. Timing gear or timing chain noises are not ' excessively loud, but thev are difficult to locate and remove without considerable dismantling. Silent chains ns thev are used today have an adjustment adjust-ment for taking up wear, and the heliyal eear drives ar usually pret t v quiet, which could not be said for the spur ..ears that, usoi to be commonly used. Ignition Noises. The auxiliary shn fts on the engino arc not likelv 'to give any trouble unless un-less their bi'bri cation is neglected, so that rapid wear in the bearings takes place. . ' One of. the most troublesome knocks is that, caused bv preigni t im. It. is easv to distinguish this metallic knock, hut there are so many possible causes Hint it not easy tn run down the real one. Of course, it may be due dimply lo the spark hein ton far ad va need, but, in the other hand, it may ho 'au-cd bv carbon deposit--, faulty liming, lim-ing, poor mixture. The only course to pursue in this case is to run down the real cause of the trouble by process of elimination, and then apply the obvious cure for that baie cause. While the merino i.i the commonest location for noises, it has no monopoly on this very annoying accompaniment to motoring. The" other mechanical units are, quite likely to develop noisy g operation. The clutch smet imr-; de-Y de-Y '-'lops buekiniT, with a raMling under the floorboard:! Hint is intensely annoying. an-noying. A worn tin-end bearing wiP huso this, md ns the lubrication "f this part, i frequently neglected, thb is likelv enough to be'al the bottom nf 'he trouble. The geaj-set is a very likelv scat J noisy operation. When one of the shafts is out of alignment grinding and growling of the gears will ensue.- Wnrn hearings are a likely cause of thif-t thif-t rouble, but the owner should have the misalignment eorreeted at once, because tho eond it ion produces not ouly noise but broken gears and heavy repair bills. Minor Squeaks. The propeller shaft and universal .mints seldom give 1 rouble, in spit e of the strenuous part they are called upon to play. As much cannot bo said for t he rear axle, which is a f reqnen t offender. of-fender. If driving pinion and the ring or differential ni::ster gear are not running run-ning in eorrect alignment, there will be a loud hum, which is not only unpleasant unpleas-ant to the ear, but. presages trouble for the poekelhook. "When the pinion and gear clearance is not correct there is a No a humming neeompanintenr, 1u operation. Adjustments in this unit usually usu-ally require the shifting of the whole unit, a job that is net for inepert hands, and. in general, it. may be said that trouble in the rear axle .b'aiaipls The best me'dianieal -jjirdical attention that can bo got. Of euursc. there are many minnr srpieaks and rattles from fenders, wheels and all the rods and linkage on and nndr the -i-hassN. The only remedy rem-edy is to give the whole works a going over and tightening from time to time. As the car grows older the need for this increases. In fa'-t, the best) general gen-eral advice that can be given in this connection is to take care of the lubrication lubri-cation of the c;ir; let, it, be eorre.-t and copious; giye the car a going over cure i wo'k with the wrench , tightening jeor- jMa: Jf-. ' - to have loosened. aii.W JT reis.m"w. -.ou should imy ,'1"ii"'J tn the. cud of the war " 'fi'rl,"i and sweet nnunng car I' ;illliiblc indicant of its ' ,i-f " |