240Z Distributor Internal Parts Questions

[HappyZ]

In the process of installing my Pertronix Ignitor II electronic points, I decided to take a look inside.  I have some pics attached and have a few questions:

The plate below has thee black tabs on the top.  I read somewhere that there should be ball bearings inside each tab.  I cleaned it a bit before reinstalling but didn't see any bearings inside (they may be there but didn't see them).  If they are there, should I clean under the tabs better and put some grease in there?  If they're missing, what should I do?

 

What does the screw on the top of the plate do? It seems to pivot on a cam?  As I turn it, it doesn't come out, but seems to pivot in a circle.

 

What is the stuff inside the spring of the vacuum advance?  Also, It's very hard to push in and out...is that normal?  Also, if the diaphragm is bad, is there a way to repair or replace it?

[Zed Head]

Looks like the very early distributors didn't have the second set of ball bearings.

1972

[Zed Head]

[HappyZ]

I took the top half apart again and cleaned thoroughly.  I greased the areas you indicated  and the guide (except the lower half).  I must say that no matter what I did, the plates on the disc in the photo never really moved smoothly.  I'll put it in and see how the advance works.

Here's a pic of the distributor.

 

[Zed Head]

The breaker plate (the assembly of parts with the screw and the ball bearings) can be disassembled.  There's a snap ring in a groove that lets it all come apart.  Then you can shine up the ball bearings and the surfaces they roll on and slide against.  The black piece with the bulbous protrusions needs to be smooth inside so the ball bearings can slide.

Several people have also found that the vacuum diaphragm was shot on their old distributors.  If you're not going for reproduction you might be better off getting a newer distributor and making it work.  Keep that old one as a piece of garage art.  It has some unique features, like the external spring on the vacuum advance module.

You didn't mention the centrifugal advance pieces either.  They need to move smoothly also.  They're under the breaker plate, weights and springs.

[HappyZ]

Thanks @Zed Head!  I have a second distributor, coincidentally it's the same model.  I'll taking it completely apart and cleaning/greasing it up.  I took a lot of pics, so hopefully I can put it back together correctly.  I put the Pertronix in my current one, but may transfer to the cleaned up one when it's done.

Is there a trick to removing the shaft part of the distributor; I'd like to clean it up too?

[Zed Head]

Once you get past a certain point you kind of have to use your own tricks.  The roll pin can be hard to get out, to disassemble the shaft.

Check your timing advance movement with a timing light and you'll get a good feel if it's responding quickly and correctly.  Hook up the light, rev the engine, watch what happens.  Disconnect vacuum advance and do it again.  Hook up vacuum advance to full vacuum at idle (you have to find a port), you should get full vacuum advance immediately.

Edited February 23, 2022 by Zed Head