Valve adjustment SBC/BBC

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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. Then we will turn the crank another 1/4 turn and be back to firing on #1, where we will stab the distributor and install the retaining clamp and bolt. We will leave it a little loose so we can rotate the distributor housing. You may have to use a long screwdriver to line up the slot in the distributor drive shaft as you look down into the hole where the distributor goes.  
 
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. Then we will turn the crank another 1/4 turn and be back to firing on #1, where we will stab the distributor and install the retaining clamp and bolt. We will leave it a little loose so we can rotate the distributor housing. You may have to use a long screwdriver to line up the slot in the distributor drive shaft as you look down into the hole where the distributor goes.  
  
As if we were standing on the motor and looking down on it, we will want to point the rotor tab at #1 cylinder, approximately 5:30 O'clock if you look at a clock face. Position the distributor housing so that you can twist it both ways without the vacuum advance can hitting on the intake manifold. Replace valve covers. Replace spark plugs. Using your longest spark plug wire, plug it into the 5:30 position on the cap, coinciding with the tab on the rotor at 5:30 and run the other end of the wire to #1 spark plug. The longest wires will be for #1 and #2. The next longest wires will be for #3 and #4. Next longest for #5 and #6. The shortest wires will be for #7 and #8. Going around the cap in a clockwise manner, the next hole in the cap will take the wire for #8 spark plug, then #4, then #3, then #6, then #5, then #7, then #2.  
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As if we were standing on the motor and looking down on it, we will want to point the rotor tab at #1 cylinder, approximately 5:30 o'clock if you look at a clock face. Position the distributor housing so that you can twist it both ways without the vacuum advance can hitting on the intake manifold. Replace valve covers. Replace spark plugs. Using your longest spark plug wire, plug it into the 5:30 position on the cap, coinciding with the tab on the rotor at 5:30 and run the other end of the wire to #1 spark plug. The longest wires will be for #1 and #2. The next longest wires will be for #3 and #4. Next longest for #5 and #6. The shortest wires will be for #7 and #8. Going around the cap in a clockwise manner, the next hole in the cap will take the wire for #8 spark plug, then #4, then #3, then #6, then #5, then #7, then #2.  
  
 
Now, depending on where the timing tab is on your motor (there were 3 different positions used), you might have to rotate the distributor housing a little one way or the other to get the motor to fire off, but unless I miss my guess, SHE WILL FIRE OFF. Have a timing light affixed to the #1 spark plug wire, adjust timing and lock the distributor down.
 
Now, depending on where the timing tab is on your motor (there were 3 different positions used), you might have to rotate the distributor housing a little one way or the other to get the motor to fire off, but unless I miss my guess, SHE WILL FIRE OFF. Have a timing light affixed to the #1 spark plug wire, adjust timing and lock the distributor down.
  
A little more info about the different timing positions. Like I said, there are 3 different ones. There is a 12:00 Noon position, a 2:00 O'clock position and a 2:30 O'Clock position. Through the years, the timing tabs and front covers get mixed up on these motors, so you really should find top dead center and use the proper mark on your harmonic damper to line up with the timing tab on your front cover. Here is the procedure for doing this with the motor assembled that I wrote for the Crankshaft Coalition Wiki....
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Through the years, the timing tabs and front covers get mixed up on these motors, so you really should find top dead center and use the proper mark on your harmonic damper to line up with the timing tab on your front cover. More info about the different timing positions can be seen at [[Timing Tabs and Damper TDC Lines SBC]].  
http://www.crankshaftcoalition.com/wiki/Determining_top_dead_center
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If you can follow these instructions, the valves will be adjusted properly and the motor will be ignition timed.
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[http://www.crankshaftcoalition.com/wiki/Determining_top_dead_center Determining TDC] is the procedure for finding TDC with the motor assembled.
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If you can follow these instructions, the valves will be adjusted properly and the ignition timed and ready to start. Be sure if the engine is newly assembled or has say for an extended period of time that the oil system is first primed before starting the engine.
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===Also see===
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[[How to make a timing tape]]
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[[Camshaft install tips and tricks]]
  
 
[[Category:Engine]]
 
[[Category:Engine]]
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[[Category:Camshaft]]

Revision as of 02:38, 19 February 2012

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