In the process of drum to disc swap. What has been the cleanest/easiest way you bled out the brake lines? Just let them drain out?
I started with a "gravity bleed" but it took two more trys the old fashion way to get a good firm pedal. Be sure to bench bleed the master cylinder.
if there are any dips in the lines all won't run out, after draining the master cyl, you could undo the lines there, and blow through them.
If you mean cleaning the lines before the disc install...Just drain em off into a container. When you bleed the brakes after the disc install,you will get fresh fluid through the lines. Useing solvents/compressed air can muck up the prop valve by lodging debris in it. You can clean the lines out individually by disconnecting them from the system and running brake clean through them. Its not really necessary to blow out the lines unless you feel they are questionable/rusty inside. If you feel they are questionable you should just replace em. Dont take chances/cut corners with your brake system...Its bad gree gree...Definitely bench bleed the Master cyl if you replace it. Dont bleed it on the car...Good luck!!!
