Hi,

I have an '87 Vanagon and I'm attempting to bleed the brakes using a power
bleeder.  I've pressurized the system to 15 PSI and bled the rear brakes
fine, however when I open the bleeder on either of the front calipers no
fluid will come out.

I've read in the Bentley that on vehicles with a brake booster (mine looks
like it has this) that the vacuum line needs to be disconnected and some
lever on the pressure regulator needs to be flipped. I think I've found the
vacuum line on the booster, though I'm not entirely sure and it doesn't want
to come off, and I think I've found the pressure regulator but can find no
lever on it anywhere.

Help please, what am I doing wrong?

Thanks,
-Roger