i had this really scary noise what i thought was coming from distributor so i happen to come by a used one in good condition and replaced it.
the noise is still there.
i took my old one apart and didnt find any problem i rotated the bearing and didnt feel any grinding.
it only happends when the car is cold so for about a minute when i start it up i hear this metal on metal clunking/grinding noise and it goes away.
i listened to it a lil closer and it sound like its comin from where dizzy connects to the head and cam
is it possible that dizzy is not alligned with center of the cam where they connect?
i also hear ticking noise from head all the time for some reason. i adjuster the valves last year and the guy said there were only 2 that needed to be loosened up since they were too tight.
In my expierence the symptom you are describing is usually due to distributor bearing wear or play, even though you came across a cheap used one doesnt mean it works the way it should, why was the person getting rid of it? same reason? it is unlikely that it is not meeting with the cam correctly, it is keyed in such a way that is long as the keys look good and arnt all broken or obviously inop then the problem will lie elsware, if you have a stethascope you can better pin point the location of the noise, or even a piece of tube with a nail in one end and a paper cup on the other will work fine as half ass as it seems. You might try swaping you old and new dizzy back and forth and see if there is any difference in noise level or pitch, also make sure that the last cam cam on that side, the one that is on the outside of the valve cover is properly fit and snug, there are dowels here i belive and if you failed to put them in or lost one ect when you did you valve adjustment this could possibly be a issue, it would not be a bad idea to check the valves either, as if the clearance were off enogh perhaps on the last valve it would cause a slight knock or louder tick (and im not refering to detonation, just the sound created) when it warms up and expands it better meets the rocker arm.
what happened was i bought a dizzy on ebay and at same time friend of a friend needed one badly(coil was bad) so i sold him mine and took his since i had msd at the time.
it was very clean and looked pretty much like new.
btw our cars are naturally ticky near the head because our injectors make that ticking sound due to their design, they have an o-ring that keeps it kinda subdued, but once it wears down it becomes more evident, especially when the engine is cold and the o-rings are stiff, once they get hotter they soften up