HOW THE OEM PCV VALVE WORKS

                    BELOW, VALVE IS CLOSED WHEN     BELOW, IN NORMAL RUNNING

                    ENGINE IS NOT RUNNING           USUALLY AT CRUISE, PART OPEN

                                     ABOVE, AT IDLE, VALVE OPENING       ABOVE, AT 3/4 THROTTLE 

                   IS SMALL. AN OLD ENGINE WILL       THE VALVE IS WIDE OPEN.

                  HAVE POSITIVE PRESSURE IN THE       NOTICE VERY LITTLE SPACE 

                   CRANKCASE CAUSING FUMES TO        FOR GASSES TO PASS THRU

                   BE EXPELED AT ANY WEAK OPEN-       WORSE YET, VALVE TENDS

                   ING.                                         CLOSE AT FULL THROTTLE 

                                                                 MAKING MATTERS WORSE.

                   BESIDES THE FACT THAT THIS VALVE GETS CLOGGED BY SOOT IN 

                   TIME, IT ALSO WEARS. THE INTAKE MANIFOLD CONTROLS THIS

                   VALVE AND NEVER KNOWS IF THERE IS TOO MUCH PRESSURE

                   (BLOWBY) IN THE CRANKCASE. IT IS OUTDATED WHEN THE

                   PISTON RINGS WEAR. THIS SYSTEM HAS EXISTED SINCE 1958

                   WITHOUT AND CHANGES EXCEPT TO MAKE THE ORIFACE BIGGER.