Evening Republican, Volume 21, Number 84, Rensselaer, Jasper County, 17 April 1918 — SET OF VALVES OF IMPORTANCE [ARTICLE]

SET OF VALVES OF IMPORTANCE

Few Realize Need of Adjustment of Lifters—They Are Hard to Reach. THEY ARE OFTEN NEGLECTED Best Engine In World Will Lose Power If It la Not Given Attention at Proper Time—Twisting Wrong Nut Is Harmful. One seldom realizes the importance of correct adjustment of the valve lifters, yet the best engine In the world will lose power if these are not properly set. Since they are usually difficult to reach, dirty to handle, and do not force themselves on the driver’s attention, they are neglected until the trouble becomes really serious. Of course if they become noisy the knocking l§Bo noticeable that the owner Is forced to make adjustments immediately. But ordinarily these parts receive scant attention and so the loss of power is attributed to either the carburetor or ignition, until a thorough overhauling of the motor leads to the discovery of the real trouble. As aforementioned, they may become noisy, due to the fact that the space becomes too wide. As they rise they give a hammer blow to the valve stems, causing a knock which may readily be heard. By stopping the motor, removing the valve cover plates end shaking them up and down the ones out of adjustment may readily be located. ■

Examine Adjustment Carefully. Sometimes several are at fault, so, while about it, set all of them. Examine the adjustment carefully to understand it, for much damage may be caused by twisting the wrong nut. One is locking nut, which must be loosened first.* The adjustment nut is then set to the right distance and the locking nut. fastened. The opening should approximate one-sixty-fourth inch for exhaust valves, and three-one-thousandths iiich for inlet valves. Use an ordinary business car as a gauge for the exhaust valve clearance. If possible to have a card the right thickness it is best to do so. This can be readily measured with a micrometer. A piece of notepaper is about right for inlet valve clearance. It will be found difficult to adjust the space correctly unless the following directions are followed: Place the desired gauge in space and screw adjusting nut until it touches. Now unscrew it either one-sixth or one-fourth turn. ’Chen lock the nut that holds it in place. Try the gauge and see if it has just a slight friction. Reason for Unscrewing. The reason for unscrewing the adjusting nut is that the locking-nut pushes it up and so throws the adjustment out of true. If the clearance becomes too great the valves open late and close early. Since they should move exactly as the designer intended, it is evident that the engine will lose power if both ends of a stroke are cut off. If the clearance is too small the engine will lose compression and with it a great deal -of power. This is due to the fact that as the engine heats up the valve stem lengthens. As they grow longer they use the space between valve stem and valve lifter. If the space is too small the valve stem rests on valve lifter. As It lengthens the head of the valve is lifted off its seat in the cylinder, opening the valve and so losing the compression. It will be evident from this that valve clearance is one of the important things about a motor and one that should be borne in mind and inspected whenever one looks for causes of lost power.