Editing Valve adjustment SBC/BBC (section)
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==Adjusting the valves== Loosen both adjusting nuts on both rockers on #1 cylinder until the rockers are loose on the studs. Have your friend hold his finger on the tip of one of them so that he is pinching the rocker arm down onto the tip of the valve, holding it tightly. Now, you grasp the pushrod for the rocker he is holding down and jiggle the pushrod up and down while using a socket wrench to slowly tighten down the adjusting nut until all the slack is removed and you cannot move the pushrod up or down any longer. Be delicate here. This is not a strong-armed operation. You are simply taking all the slack out of the pushrod and getting the rocker adjusting nut very slightly tightened down against the trunnion of the rocker arm. Now, make 1/8 turn more on the adjusting nut.....1/8 turn.....45 degrees......OK, that valve is done. Now, move over to the other valve on #1 cylinder and repeat the operation. You may have heard that you can rotate the pushrod with your thumb and forefinger until the pushrod gets tight and use that for adjusting the valves. While that may work for someone who builds motors day in and day out for a living, it may not work for someone who has no way of knowing how much resistance they should be feeling. Jiggling the pushrod up and down is BULLETPROOF and can be done successfully by even a first-time builder. Now, you have both valves adjusted on #1 cylinder. With the socket and ratchet on the harmonic damper retaining bolt head at the crank, turn the crankshaft 1/4 turn clockwise. That will mean that the mark you made on the damper ring will move clockwise from NORTH to EAST.....STOP. Make another mark on the damper ring at the straight-up position. Now, you will have a mark at EAST and a mark at NORTH. You have moved the crank 90 degrees and into the next cylinder's firing range. There are 720 degrees in a full cycle to fire all 8 cylinders, so turning the crank 90 degrees at a time will allow us to adjust the valves on all 8 cylinders with just 2 full turns of the crank. If you knew that a small block Chevy's firing order is 1-8-4-3-6-5-7-2, then you would know that it is #8's turn to fire. Go to #8 and loosen both adjusting nuts, just like you did on #1. Have your buddy hold the rocker down against the valve stem while you jiggle the pushrod up and down to remove all play, all the while slowly turning the adjusting nut to remove the play. When all the play is removed, tighten the nut another 1/8 turn. Move on to the other valve on #8 and do the same. Now, you have adjusted the valves on cylinders 1 and 8. Put the socket on the crank nut and turn the crank 1/4 turn to the right (clockwise, just like before). Place a mark at the top of the inertia ring like you did last time. This mark will be at NORTH. The mark you had at EAST will move to SOUTH and the one you had at NORTH will move to EAST. Following the firing order, we will now go to cylinder #4 and adjust both valves. Then we will move the crank 1/4 turn and make another mark and do cylinder #3. Then we will move another 1/4 turn (the crank has marks for each 1/4 turn now) and do cylinder #6. Then we will move the crank another 1/4 turn and do cylinder #5. Then we will move the crank another 1/4 turn and do cylinder #7. Then we will turn the crank another 1/4 turn and do cylinder #2.
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