delta shower fixture leaking - naval jelly too strong?

[cbean]

I have replaced the inner ball & rubber inserts & springs in my 40+ year old Delta shower several times in the past year. The changing outs only results in a week or so of the leaking stopping.

In looking inside the fixture with the ball out I see that the copper inside has turned green. Would any particular brand of Naval Jelly be too strong to use? What would you recommend, assuming that removing the corrosion inside there would help make a better seal between the fixture & the rubber & the ball.

[JoeSpareBedroom]

Try something else first: Drop the entire shower head into a bucket of vinegar that's no hotter than the hottest water from your tap. Soak it for an hour, then scrub the encrusted areas with a toothbrush. For spots too small for the toothbrush to reach, pick up a couple of non-metallic Dremel brushes. You don't necessarily have to own a Dremel tool to use the attachments in this way.

[RayV]

Joe has the right idea. I have had to soak some overnight because the crust was so thick.