420 SEL ball studs loose
 

Should the ball studs revolve in the head? About half of mine spin freely but the picture of a new one shows threads. What's the deal?:confused:

Gregga

Are you referring to the *engine* ball studs?

Haasman

There are two parts to a ball stud. The ball itself is part of the plunger and will spin. The outer part screws into the head and most certainly should not spin.

Yes, the engine ball studs are loose in the heads. I had the engine apart to put in a short block and out of curiosity grabbed the hex with my fingers and it spun free. I tried to tighten it but it felt like there was no resistance, like two machined parts sliding, not like stripped threads. I have one on that side that's making a lot of noise but almost feel afraid to get into it if the threads are all gone.

My experience is with the 380, but I would be very surprised if the other engines did not have screw-in ball studs.