I need to check the timing on my vehicle. But the gentleman who had the vehicle before me painted the engine but put the pulley on about 180 out.  I need to re-mark it so I can do this right. One problem..I've never manually checked for TDC (Top Dead Center). What do I need to know ? And do I need another person to assist? Or is this best left to the experts ?

 Jim

It seems very unlikely that the pulley is 180 degrees off.  The mark is actually on the balance wheel, or the pully is indexed to the balance wheel.  The balance wheel is on a key way to the crankshaft.  The only way it could be off of the correct position on the crank is if the key way is sheared or missing.  But that is possible.  If the key way is in place and the mark is in fact not at TDC, the the outer part of the balance wheel is spinning, and the balance wheel needs to be replaced.

Remove the #1 spark plug, and remove the distributor cap.  Rotate the engine by hand until the rotor is approaching the number one position on the cap ( or where the position was before you removed the cap ).  Now watch in the spark plug hole and watch the piston, or reach in with a soft stick, plastic, thin wood etc. NOT METAL, and feel for the top of the piston. Be carefull not to jamb the stick/feeler in the cylinder as the piston comes up. Continue to slowly rotate the engine until the piston is at the top of its travel.  When it's at the top, you are at ( or near ) top dead center. 

You will now need to turn the crank back and forth a small amount to become more accurate.  You will notice a very small amount of crankshaft rotation that seems to not move the piston.  The is due to the fact the piston is at TDC, and the connection rod is moving more sideways than up and down.  Center the crank in this area of no piston movement.  You are now at top dead center on #1.

TDC is #1 piston all the way up on the compression stroke. The best way would be to remove the valve cover and watch the the rocker arms. When both push rods are all the way down, the valves are closed. If they are properly adjusted, the rods should be just a bit loose to where you can rotate them. It wouldn't hurt to have a helper "bump" it over to get it close, but to get it dead  on, you may need to put a socket on the front pulley (harmonic balancer). This exercise will be much easier to accomplish if you first remove all the spark plugs and just do it by hand. If the balancer is not in correctly, you may want to remove it and reset it to avoid confusion later.

Somebody scream at me if I'm telling you wrong.

[QUOTE=daveb12]

TDC is #1 piston all the way up on the compression stroke. The best way would be to remove the valve cover and watch the the rocker arms. When both push rods are all the way down, the valves are closed. If they are properly adjusted, the rods should be just a bit loose to where you can rotate them. It wouldn't hurt to have a helper "bump" it over to get it close, but to get it dead  on, you may need to put a socket on the front pulley (harmonic balancer). This exercise will be much easier to accomplish if you first remove all the spark plugs and just do it by hand. If the balancer is not in correctly, you may want to remove it and reset it to avoid confusion later.

Somebody scream at me if I'm telling you wrong.

[/QUOTE]

Ken's smarter than me, I didn't even think about the keyway or bad balancer

I knew someone would be able to explain it in terms I could understand.... 

 

 Thanks !

  Jim

Dave, looks like we were both typing at the same time.

Removing the valve cover can be necessary when the engine isn't running, but when the engine runs it's a lot easier to just point the rotor toward #1 to start with.  It has to be close, or it wouldn't run.

And you are right, it is a lot easier to turn the engine without the spark plugs installed.

kstyer38397.720787037

pull coil wire or disconnect 12V to HEI, hook up remote starter SW to starter or have a helper bump the starter for you, pull the dist. cap, mark where #1 is on dist. pull #1 plug, put your finger over #1 plug hole, bump the starter, compression will try to push your finger off #1 plug hole, look at dist.as you do it, you might have to do it several times till you get it, all you have to do is be close, use a belt wrench on dampner pulley if you can not a socket in crank bolt to fine adjust TDC, you might over tight or loosen bolt.