valve adjustment
Burning Brakes
Joined: Sep 2009
Posts: 1,124
Likes: 140
From: Western New York
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
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
Melting Slicks
Joined: Oct 2011
Posts: 2,748
Likes: 90
From: Sacramento California
C2 of Year Finalist (performance mods) 2019
2018 C2 of Year Finalist
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.
Ive always done hid lifter with the car running, but C Straub explained a very easy way to do it cold.
Thread Starter
Racer
Joined: Jan 2013
Posts: 300
Likes: 10
Reply
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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Melting Slicks
Joined: Feb 2006
Posts: 3,105
Likes: 96
From: Sunrise FL
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.
Melting Slicks
Joined: Oct 2011
Posts: 2,748
Likes: 90
From: Sacramento California
C2 of Year Finalist (performance mods) 2019
2018 C2 of Year Finalist
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?
You did check and get correct length pushrods...right? And the rockers aren't hitting the top of the springs?
Instructor
Joined: Nov 2013
Posts: 220
Likes: 17
From: Pasadena MD
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.
Safety Car
Joined: Jan 2009
Posts: 4,000
Likes: 299
From: New York
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 .
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 .
Team Owner
Joined: Jan 2006
Posts: 37,637
Likes: 3,114
From: Crossville TN
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.
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.