Carbon button in Marelli distributor? Help.

So I’ve been chasing a rough running hart start condition on my ‘80 ‘i’ NA spec and took off the distributor caps looking for answers. Found one of the carbon buttons had turned chalky and seems the spring is not keeping it well, sprung. What is the purpose of the button and how do you get the spring in the hole when it’s diameter is wider than the hole? Could this be part of my problem? Here is a pic. Thank you.
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Hard start and difficult to get to rev.

 

For comparison here is the other distributor’s carbon button. Spring loaded and not chalky.
View attachment 2492037

 

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Didn’t mean to post this pic. Can’t see a delete function so please disregard.

 

By "winding" the spring in the direction of the coils (i.e., sort of wedge the back end of the spring into the hole and then twist the spring in the direction of the coils to reduce its diameter while pushing it, and the button, in).

Yes. You need the spring-loaded carbon button to be in contact with the metal surface of the rotor. Any "gap" there is another gap that the spark needs to jump. Your "bad" button looks broken where the spring attaches. Pull out both and compare them.

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Thank you!

 

The carbon button is part of the HT circuit from the coil to the individual spark plugs. It connects the coil lead to the top of the rotor arm which then connects to each spark plug lead in turn as the rotor rotates in the distributor cap. So it's pretty important that it makes good contact!

 

I always put it in but never mind even realized that until now. I thought maybe it was something that absorbs wayward sparks or I dunno ‍♂️ what. Makes sense now that I think about it. Sends current from coil into rotor arm, rotor connects to each contact as it spins etc. Going to order new ones. Hope I can get the damn spring in right this time. Know it’s easy if you’ve done it but I had a helluva time getting it in last time and this problem was end result. Luckily they’re cheap I guess.

 

Just for clarity it doesn't connect, it gets really close and the spark jumps the gap. But yes, you have the idea exactly right.

 

I see. Thanks