A little heat did the trick

[STRADALITE]

Here’s a bit of knowledge I’m passing on.
I recently bought this seat to restore. First order of business is to take it apart. You can tell from the pictures that won’t be an easy feat.
The screws at the end of the bell cups wouldn’t budge. Normally several days of PB Blaster will help loosen nuts. This setup won’t allow for the Blaster to penetrate the threads. I used a trick that I’ve heard here before. I heated the screws with a propane torch and let them cool. After that they came out with zero resistance.

 

[tacochris]

Yessir! The method i use is to heat em up good and hot and then pour water on them. The rapid cooling shocks the rusted threads loose. Bailed me out of alot of jams with bikes and cars.

 

[catfish]

It's a great tool to have!

 

[SirMike1983]

PB Blaster isn't bad but for really stuck stuff, Kano Kroil or 50/50 ATF/Acetone are good options. I heat the part more or less dry, then add the oil right after halting the heat so that as the part cools, it draws in the oil. A propane torch is a must-have with these oils if you have rusted parts. I prefer the Kroil over ATF/Acetone because the acetone component can ruin paint and dry stuff out.

 

[bobcycles]

Yes Sir...always the best solution when the usual PB etc stuff is useless