I have been trying to bleed the brakes in my '84 380 SL after the system drained itself. I don't yet know why the system drained itself. I have had the same thing happen on other cars, but I would put fluid back in, bleed the brakes, and everything was fine. I put fluid in the reservoir that same night.
But this one won't bleed.
I tried putting a hose on the bleed nipple with the other end in a bottle with a little fluid, open the nipple, then pumping the brakes. Nothing came through.
Next I put a vacuum bottle on the open bleed nipple and got nothing. But the vacuum held. I also tried pumping the brake while it was on the bottle. Still nothing.
Both rear wheels have been tried with nothing to show for it. I'm stumped and thinking that the master cylinder is to blame somehow.
Where do each of the three lines from the master cylinder go? The front line go to the front brakes and each of the opposing rear lines to a rear wheel?
And where did the brake fluid go in the first place? There are no stains on the floor or in the wheels?