So far I've tried tapping it with a sledge, backing it into a concrete barrier, WD40 and Liquid Wrench.

BF, October 2009

Seized checklist,
1. tap with hammer
2. bang with hammer
3. repeat 1 & 2 with increasing force and hammer size
4. Apply heat (blow lamp, acetaline torch) and repeat 1 - 3

Try and work the thing back and forth and have several goes at it.
Didn't mean it to sound funny but sorry that is it.

Jmmy, November 2009