Rusted Exhaust - Help

[mike87]

Hi, got an '87 325is with a pretty rusted exhaust. I finally managed to get the area after the cats disconnected, was wondering what nut size the section that connects the downpipes to the headers is - there's 6 nuts. Also, is there a special technique? Do I need a 13mm socket + u-joint + extension + ratchet? I tried just a 13mm socket and it couldn't fit over the nut, but a 14mm seemed too large. I'm unsure because the nuts are so rusted.

I didn't want to force it. Any help would be appreciated! Currently letting the nuts soak in WD40 overnight and picking up some PB Blaster later this week.

[lateracer]

For the always rusted exhaust stud nuts, I do the WD40 over night thing - more than one night if possible - and turn them off slowly using a 3 foot breaker bar I have. Too fast will pull the threads off the manifold stud (ask me how I know).

Yeah, I think it's a 14mm nut. They're usually copper, which is soft, so you can feel them "give" a little when you start putting on the pressure.

[SkinnyVT]

use 6 point sockets whenever you can as well, with the rust either pound the correct size metric socket on there or sometimes an english socket may fit better and like always heat is your friend