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"Valve Lash" Adjustment - GM L6 250 cid...

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  • "Valve Lash" Adjustment - GM L6 250 cid...

    Okay, on my new longblock, it came with a note on one of the push rods to:Before installing the valve cover, be sure to check valve lashUh... How do I do this? I read some in one of my manuals, but it didn't help much.
    1990 Cabo 204 Centercon Yamaha 150

  • #2
    Re: "Valve Lash" Adjustment - GM L6 250 cid...

    You can do it running or static. Running is messy so static is generally the way to go. Head to your library and get the procedure from any of their shop manuals for any version of the Chevy inline 6 (198, 230, 250, or 292 CI) from 1961 forward. This does not include the 235 CI "stove-bolt" six used in full size chevy's through the 1962 model year but does include those after that. Make sure you are looking at INLINE SIXes. Not the V6's.


    • #3
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      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. valve adj. engine stopped1. remove valve cover.2 adj. valves when lifter is on the base circle of the camshaft lobe as follows: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). 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. No. 1 cylinder--exhaust and intakeNo. 2 cylinder--intakeNo. 3 cylinder--exhaustNo. 4 cylinder--intakeNo. 5 cylidner--exhaustc. 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).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:no. 2 cylinder--exhaustno. 3 cylinder--intakeno. 4 cylinder--exhustno. 5 cylinder--intakeno. 6 cylinder--intake and exhaust3. install distributor cap and spark plug wire assy. install rocker arm cover and adjust carb. engine runningfollowing procedure, performed with engine running, should be completed only if readjustment is required. 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....
      'Lime Time'
      1975 AristoCraft Nineteen
      Mercruiser 165hp (chevy 250 L6), MC-1 drive