meathead

So I am going to replace the O-ring on my distributor. Does the crankshaft need to be at TDC before I remove the dizzy?

ezone

No, that can be anywhere.

Remove the dist cap.
Note carefully the position of the rotor, this will be needed for reinstallation

Make a reference alignment mark on the leg of the distributor base across the casting sticking up out of the head, so you can get the dist reinstalled and aligned in the exact same position it started before removal.....this way you don't have to retime it with a timing light.






I sometimes use a chisel to make the marks, it's quick.
Maybe someone has already marked yours here.
A single mark is good enough, when you get a bunch of lines on here it can get confusing.






Remove distributor, replace O ring.


When you go to reinstall, push the dist into the hole gently, then rotate the rotor slowly to align the drive lugs between camshaft and dist end, when you get it in the right spot the dist will easily go all the way into the hole and seat flat against the head.

It will only go all the way in one spot. Do not force it.