Adjust valves SBC BBC

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Remove spark plugs.
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*Remove spark plugs.
Remove valve covers.
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*Remove valve covers.
Remove distributor.  
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*Remove distributor.  
Standing at the front of the motor, at the water pump and looking toward the rear of the motor, #1 cylinder will be on your right, the first one, just behind the radiator. The next one to the rear will be #3, then #5, then #7 will be the last one on the driver's side, next to the firewall. Looking on the other side of the motor, the passenger side, the front cylinder will be #2, the next one to the rear will be #4, then #6, then #8 all the way to the rear against the firewall. Do whatever you have to do to get this all fixed in your mind. If you have to make a diagram on a large piece of paper and sit it against the carburetor, then do it. Knowing which cylinder is which cannot be over-stated.  
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Standing at the front of the motor, looking toward the rear of the motor, #1 cylinder will be on your right (driver side). #1 is the first one, just behind the radiator. The next one to the rear will be #3, then #5, then #7 will be the last one on the driver's side, next to the firewall. Looking on the other side of the motor, the passenger side, the front cylinder will be #2, the next one to the rear will be #4, then #6, then #8 all the way to the rear against the firewall. Do whatever you have to do to get this all fixed in your mind. If you have to make a diagram on a large piece of paper and sit it against the carburetor, then do it. Knowing which cylinder is which cannot be over-stated.  
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Also, knowing which way the crankshaft turns and which way the distributor rotor turns cannot be over-stated. As you are standing at the water pump, the crankshaft turns clockwise, the same way the hands on an analog watch or clock turn.  
 
Also, knowing which way the crankshaft turns and which way the distributor rotor turns cannot be over-stated. As you are standing at the water pump, the crankshaft turns clockwise, the same way the hands on an analog watch or clock turn.  
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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.  
 
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 THIS TIME. Have a timing light affixed to the #1 spark plug wire, adjust timing and lock the distributor down.
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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 THIS TIME. Have a timing light hooked up to the #1 spark plug wire (#6 can be used if it's more convenient), adjust timing and lock the distributor down.
  
A little more info about the different timing positions. Like I said, there are 3 different ones. If you were to stand up over the motor and look down on the harmonic damper, 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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Info about the three different timing tab/damper TDC line positions can be seen '''[http://www.crankshaftcoalition.com/wiki/Timing_tabs_and_damper_TDC_lines_SBC HERE]'''. If you were to stand up over the motor and look down on the harmonic damper, there is a 12 o'clock noon position, a 2 o'clock position and a 2:30 o'clock position. Through the years, the timing tabs and front covers can 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:
http://www.crankshaftcoalition.com/...top_dead_center
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[http://www.crankshaftcoalition.com/...top_dead_center Determining top dead center]
  
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==Other wiki articles==
[[Category:Engine]]
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*[[Adjusting hydraulic lifters]]
[[Category:Adjust valves]]
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Latest revision as of 21:26, 24 July 2012

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