Salt Lake Herald-Republican | 1919-09-14 | Page 31 | How to Detect and Remedy Leaky Valves

1 r- r HOW TO DETECT H t. t AND REMEDY LEAKY VAt VALVES VES f tj ti E Expert pert Explains Best l IC Methods Meth 1 to Determine When h ht Grind t. t 2 to f It Is Just a as Important to know now valve vahe as to l know now when not to grind a r I f j 4 when grinding s Ia Is necessary ssan Is th the 7 advice nd given Riven by Arnold P P. Yerkes in hi an article on Valve o Inspection and Grinding In Motor It Is quite well motorists that not all aJl known by many valves vales engines run better after aCter the havo have been round groundS a n fact which is at attributed attributed at- at to tho the unnecessary grinding which makes for leak leaky valves The writer in his article points out how hoss one may Inny distinguish a valve that leaks from one that thal docs does not and tells how only the fault faulty ones should be ground round In Ho Re says On a a. properly cooled engine and one whore the thc cs arc ale properly timed Umed it t ma may bo be accepted as asa asa a general rule that valves which are arc ev evenly over and therefore have perfectly black heads are holding while those which are arc red or brownish metal J nn nr- nr V the i without ith t t's a covering of s soot ot or carbon carbon I arc are leaking By Dy observing the tops o of the valve alve heads as soon as ns the hc cylinder head Is removed and ad then carefully inspecting the face of the valve aho and the scat one will quickly quick le learn rn to tell what is n needed The reason for the difference In Ut the ine looks of ot the tops is simple and obvious obvious During tho UIO ous otis upon a little thought a. power stroke of oC the piston the burning gasps gases arc under high pressure If H there is the slightest leak at any f point around the face of the valve val the j J. J gases gacs aMes will force torce their wa way through at terrific speed and carr carry awa away any carbon carbon car- car bon hon which ma may have been formed on if the top of or tho the valve vahe near the leak a awell as well as on the casting near the thealo valve o Y scat leaving the thc metal the tho I leak leal entirely clear of oC oft t tt t or carbon Not ot only will tho the escaping gas carry carr J j i away vay all carbon near the leak but 1 will ivill also actually actual wear year awa away the metal itself If Ir not atlen attended to A A valve ahe which is allowed to leak for a long time will vill frequently show J quite a path ero eroded b by the tho hot ho gases 1 In rushing through tho the opening in inV V tJ much the sam wa way as tho the Sas gases gass from in high high- the burning powder charges a u power rifle or cannon gradually erode the metal of the rifle rUle or cannon e. barrel b by escaping past the projectile before It gets Cull fully under way The paths r t t i. i iv 1 th thit si P In n either case look luok w J n almost as though the tho metal ha had been melted out and there is undoubtedly a certain amount of melting meiling of or theme the tho me metal tal brought about b by the tho hot hOl gases Tho The high temperature of or the escaping InS ing gases ases also causes a diC different erent color I of the metal met around a a. leaky valve Inman Inmany in inmany man many cases Very frequently a leak leaky will have a reddish appearance like burned clay or liko like a a. furnace grate often orten shows after aCter being under undera a vcr very hot hol fire tire for some time This Is ls not an infallible rul rule for detecting a leaky valve but on man many engines It Itis is Isa a n very reliable indication I II I