Re: "Valve Lash" Adjustment - GM L6 250 cid...
i'm assumein ya have a 73 IL6. this info should cover it. merc manual C-90-68648 vol. 1. <br /><br />valve adj. <br />engine stopped<br />1. remove valve cover.<br />2 adj. valves when lifter is on the base circle of the camshaft lobe as follows:<br />a. mark distributor housing with chalk at No. 1 and No. 6 cylinder positions(plug wire), then disconnect plug wires at the spark plugs and coil and remove distributor cap and plug wire assembly(if not previously done). <br />b. crank engine until distributor rotor points to no. 1 cylinder position and breaker points are open. Following valves can be adjusted with engine in No. 1 firing position. <br />No. 1 cylinder--exhaust and intake<br />No. 2 cylinder--intake<br />No. 3 cylinder--exhaust<br />No. 4 cylinder--intake<br />No. 5 cylidner--exhaust<br /><br />c. back out adjusting nut until lash is felt at push rod, then turn in adjusting nut until all lash is removed. This can be determined by checking push rod side play while turning adjusting nut. (fig1)When play is removed, turn adjusting nut in 3/4 additional turn(to center lifter plunger).<br />d. crank engine until distribuor rotor points to No. 6 position and breaker points are open. Following valves can be adjusted with engine in No. 6 firing position:<br /><br />no. 2 cylinder--exhaust<br />no. 3 cylinder--intake<br />no. 4 cylinder--exhust<br />no. 5 cylinder--intake<br />no. 6 cylinder--intake and exhaust<br />3. install distributor cap and spark plug wire assy. <br />install rocker arm cover and adjust carb. <br /><br />engine running<br />following procedure, performed with engine running, should be completed only if readjustment is required. <br /><br />thats what the book had to say about adj. yer valves. the pic., fig. 1 is a hand holding a pushrod between thumb and index and middle finger, socket on the adj. nut and a hand on the ratchet....