@oldtimer, Good point about rusty bleeders. I always use a good penetrating oil before cracking the bleeders so I don’t literally crack one off. So far it has worked for me.
I flush my brakes every 2 years, using DOT 4
No stuck bleeders so far
I also use my own adapters for the pressure brake bleeder. The main advantage is I don’t need to ask anybody for help
I’m not a fan of the vacuum brake bleeders. In my opinion, it’s better to flush out the fluid under pressure, with fresh, versus pulling a vacuum. In which case you’ll have to periodically check the master’s not empty
Amateur question of the day:
If you spray penetrating oil on the bleeders, could the oil not penetrate down the entire depth of the threads into the caliper, and contaminate the brake fluid?
No. The bleeder seal is at the bottom of the threads.