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Old Jan 22, 2015 | 07:15 PM
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Default valve adjustment

L-82 pace car. New heads. what would you expect the engine to do if you adjusted the valves and DID NOT adjust tight enough to takeout all the lifter lash?
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Old Jan 22, 2015 | 07:20 PM
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Clatter.
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Old Jan 22, 2015 | 08:28 PM
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+1 - shacka shacka shacka........
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Old Jan 24, 2015 | 08:47 PM
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tick tick tick
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Old Jan 24, 2015 | 09:06 PM
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Caryb78,
What is your car doing? Tell us the sounds and symptoms and maybe we can help. Maybe you overtightened, too. That seems to be something that's done more often than not by first timers to valve adjustments. Fill us in, please.
Duane
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Old Jan 24, 2015 | 09:27 PM
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Hydraulic lifters w/correct preload leave you w/zero lash. Sounds like you might have adjusted, thinking solid lifter which needs lash.Maybe?
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Old Jan 25, 2015 | 10:52 AM
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Too loose and you will hammer the end of the valve into oblivion.
Ive always done hid lifter with the car running, but C Straub explained a very easy way to do it cold.
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Old Jan 25, 2015 | 07:17 PM
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Originally Posted by Duane4238
Caryb78,
What is your car doing? Tell us the sounds and symptoms and maybe we can help. Maybe you overtightened, too. That seems to be something that's done more often than not by first timers to valve adjustments. Fill us in, please.
Duane
I just installed alum. heads, 1.6 lift rockers. Adjusted per comp. instructions but didn't run right, so I backed off a little on the adj., still not running right, hard to describe .so I went to you tube some say tighten 1/2 turn, some others say 3/4 turn, Haynes says one turn, . Right now I am at 3/4 turn it runs ok no real clatter but some noise from exhaust that sounds like a skip in the exhaust flow. Engine is not shaking, smooth, accelerates from idle ok, just doesn't sound right.
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Old Jan 25, 2015 | 07:34 PM
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I use 1/2 turn. Do one cyl at a time, start at #1, follow firing order. You will have to mark the damper pulley for four divisions (90 degrees each). Turn clockwise (tighten crank bolt), and go around twice.
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Old Jan 25, 2015 | 07:48 PM
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Ignition more likely than lifters. Check for an arcing plug wire.
You did check and get correct length pushrods...right? And the rockers aren't hitting the top of the springs?
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Old Jan 25, 2015 | 11:22 PM
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Originally Posted by caryb78
I just installed alum. heads, 1.6 lift rockers. Adjusted per comp. instructions but didn't run right, so I backed off a little on the adj., still not running right, hard to describe .so I went to you tube some say tighten 1/2 turn, some others say 3/4 turn, Haynes says one turn, . Right now I am at 3/4 turn it runs ok no real clatter but some noise from exhaust that sounds like a skip in the exhaust flow. Engine is not shaking, smooth, accelerates from idle ok, just doesn't sound right.
I always do one valve at a time.put valve on heel of cam and tighten until pushrod can still be turned by hand then one half of a turn.this will work for any hydraulic cam
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Old Jan 26, 2015 | 06:25 AM
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Easiest way to adjust valves on a SBC for those who are not use to doing it is with it running. Set them up as instructed , but once the motor is together go back an check them and do this final adjustment.

Start motor
Go to number 1 cyl ... loosen the nut slowly until you here a tick tick tick tick tick .. Now slowly tighten the nut until that ticking is gone STOP you have zero lash. Now center ratchet handle at 12oclock and 1/4 movement at a time add your 3/4 turn to the rocker .. OR 1/4 or 1/2 or 1 full turn . to know which one to use contact the lifter company .
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Old Jan 26, 2015 | 04:58 PM
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Most 'experts' use the "spin the pushrod" method to determine where zero lash is. With practice that is easy to do. For folks with not that much experience, the "shake the pushrod until the slack is removed" method works better. Make certain that each valve you adjust has its lifter OFF of the cam lobe when you make the adjustment.

Whether you dial in 1/2 or 3/4 more turn [after zero lash] is not really important, unless you are building something to get a lot of RPM's. For normal street use, I use 3/4 turn.
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