Please help:Cannot loosen frozen nut on hydraulic line!
 

Hi,
I am struggling to loosen the 12mm nut on one of the hydrualic lines attached to the level controller valve on a 95 wagon. I soaked it in liquid wrench for at least 24 hours and then attempted to loosen with a line-wrench. No avail, nut will simply become rounded if I persist.
Any ideas on how to get the bugger off? The wrench is not a Craftsman. Bought a Pep-Boys. Perhaps it is the issue? Is there a better oil then Liquid wrench?
Thanks in advance
farrukh

I know what you are talking about. I just succeeded at undoing an hydraulic (brake) line on my old Vette.
No amount of soaking with 3 different "miracle loose-nut" helped me.
I ended-up using a propane torch on the d"""" thing. It came off very easily.
Good luck

Huh, using a propane torch is an accepted/ recommended technique? I assume one just heats the nut so that it expands and then one screws it off? Any risk of igniting the penetrating oil which is already soaked onto the assembly?
thanks

JackD, I hope you didn't get the metal red-hot. Brake line is made from product called Bundy tubing. It's essentially spiral-wound (like your paper towel tube) steel held together with braze. At elevated temperatures you get a phenomenon called Liquid Metal Embrittlement, where the low melting braze attacks the grain boundaries of the steel leading to intergranular fracture. This would be a sudden failure if your brake lines were to let go.

With brake lines the corrosion plus the very soft steel make it nearly impossible to undo using conventional mechanical means. Corrosion is usually strongest at the head/tube interface, not at the threads. I simply cut the line near the head, use a 6-point socket to remove the threaded piece, and replace the line as a unit.

Ketas: I was replacing the brake line, so saving it was not my goal.
Yes, it cought fire with all of the loose-nut liquid that had dripped all along the frame. It's part of the fun of working on an old car.