I just adjusted valve lash - did I do it the best way?

Discussion in '1973-1991 K5 Blazer | Truck | Suburban' started by TX Mudder, Nov 27, 2001.

  1. TX Mudder

    TX Mudder 1/2 ton status

    Jul 10, 2000
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    I just lashed the vlaves on my rebuild.
    I checked out Comp Cams site and they show one way to do it and it was a PITA time-consuming way. You have to turn the crank till the exhaust pushrods starts to go up, then adjust the intake's nut to zero plus 1/2 turn, then let the intake go all the way up and then downthen you can do the exhaust. Then do it for 7 more cylinders. I'd have been at it for 2 hours I'm sure.
    Looking in my truck books and engine books I think I found a good way.
    Put #1 cylinder at TDC.
    Just put the line on the balancer in line with zero on the timing chain cover tang. To find out if it's really on TDC on the compression stroke, just move the crankshaft a few degreed forward and backwards and if the pushrods remain still you are at TDC on the right stroke. Otherwise turn the crank 360 degrees and check it again and you know you're there.

    Now turn the nut on the int. and exh. for #1 till there's zero lash plus 1/2 to 3/4 turn (I did 3/4) turn. You're done with #1.

    Turn the crankshaft 90 degrees. That's pretty easy to do if you mark the balancer with some whiteout or something. Now adjust the next cyclined in the firing order, #8.
    Again turn it 90 degrees and do the next cylinder, which is 4. Do that till you've done all eight and you've rotated the crank a full 720 degrees. It took maybe 15 minutes and was easy.

    My question is: Is this the best way to do it? In the back of my mind I wonder if there's some problem with doing it this way (I read it in the book, I didn;t make it up myself.) I mean, a lot of people whine and moan about how time-consuming it is to lash the valves and if this is a good way wouldn't everyone do it?
    Anyway, it looks right and I went by the book. Next up is the oil pump and priming the engine. See y'all later.
    -- Mike

    <font color=blue> Married to a woman who understands the need for <font color=orange>Hugger Orange. &lt;img src="http://coloradok5.com/forums/images/icons/tongue.gif"&gt; <font color=blue>
  2. Sparky

    Sparky 1/2 ton status

    Aug 20, 2000
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    San Antonio(summer) Texas A and M (school year)
    The only two ways i have heard of doing it are...

    by ear wheile the engine is running

    and by putting the moter at TDC adjusting certain intake and exaust valves then rotating another 360 to TDC of exaust stroke and adjusting the rest of the valves

    When all else fails... Check the blinker fluid.
    78 K-5
  3. Thumper

    Thumper 1/2 ton status

    Feb 17, 2000
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    Alberta Canada
    Well, you can get a rough setting before you start by just doing it by the book, then run the motor and redo them by ear. eg: stop the rattle and turn 1/8 turn more. BUT! You have to do this after the engine has been turned over with oil pressure or it wont start. The hydraulic lifters pump up and wont let any of the valves close if you have adjusted them like the book says before you start it....


    <font color=blue>Thumper
    85 Fullsize Jimmy
    <font color=red>Aint Skeered!! </font color=red>
  4. shawnboy

    shawnboy 1/2 ton status

    Jun 22, 2001
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    Toronto, Canada, eh.
    Another good idea is to prime your lifters Helps for initial adjustments and probably save you from colapsing a lifter(s).

    <font color=red>If you are having too much fun it's probably illegal.</font color=red>
  5. 8_YOUR_H2

    8_YOUR_H2 1/2 ton status

    Feb 20, 2000
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    I did mine the same way you did. I think it is the best way to do it.
  6. FWP


    Oct 11, 2000
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    Prescott Valley, AZ
    That's the way I just did mine, except 1 turn in (new lifters). Also, I pumped the lifters full of oil first. That's pefectly fine to do it that way.

    Looks like me and you are working on the same thing. I've been putting a motor together for the last week. almost ready.........

    <a target="_blank" href=http://coloradok5.com/gallery/75K5>http://coloradok5.com/gallery/75K5</a>
  7. i was told by an ol' timer chevy guy that the best way was with the motor running and the valve covers off. they make little plastic clips you can clip on so you don't get oil everywhere. i've done it the way you did it though- pain in the ars!

    <font color=blue> Experience enables you to recognize a mistake when you make it again.

    </font color=blue>

    POWERMAD 1/2 ton status

    Mar 4, 2001
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    there must be 1/2 a dozen ways that people adjust the valves.
    Finding a way that works for you is the way to go.
    But keep in mind that on a fresh engine with a new cam it is critical to have the valves adjusted properly when the engine first fires .
    reason being that the engine has to be run at around 2K for about 20 minutes to break in the cam.
    If you are standing over it farting around with the lash at an idle when it first fires off then you stand a good chance of buying another cam sometime soon down the road.
    I have used the intake closing exhaust opening method for along time and it always works for me.
    I start at TDC and do the #1 cylinder.
    Then turn the crank clock wise until the #8 intake starts to close, then I adjust the exhaust on #8. keep turning untill the exhaust starts to open then adjust the intake.
    Continue on to 436572.
    Or just do one bank at a time just mark what ones have been done so you don't get it all mixed up.
    No matter how you do it the crank gets turned twice.

    <font color=green> Too bad ignorance isn't painful </font color=green>
  9. 95 Silverado

    95 Silverado 1/2 ton status

    Nov 9, 2001
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    Central PA
    there are as many ways to do this as there are opinions on what is best. i have a chiltons manual that gives a method where you turn the engine to the number one firing pos. TDC, adjust so many valves (it lists which intakes and which exhausts), then you turn it one revolution, TDC no. 6 pos. and adjust the rest. I do this, then after break-in and a few miles I readjust them with the engine running. pull off one valve cover, run the engine, back off the adjuster till the lifter starts to click, just tighten it enough to make it stop, do all the valves on that side, stop the engine, then turn them down the additional amount for preload, reinstall that valve cover and do the same for the other side. The amount of preload suggested varies also, I usually use 1/2 turn, the less preload the higher the engine will rev before the valves float, racing engines use as little as 1/8 turn, the cam manufacturers recommendation might be best. I'm not suggesting this is the best or the only procedure, but it works for me.

    '95 Chevy Silverado 1500
    5.7 V8-NV4500- 3.73 rears

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