The power brakes should have assist. The hydrobooster has an accumulator
that holds pressurized brake fluid.  The vehicle should have enough stored
pressure for 4 good solid pedal pumps and then start to bleed off, getting
harder with each stroke. The system should not bleed down over night.  Get
it checked.  If the engine dies while driving it. apply the brakes and keep
steady pressure on the pedal till stopped, or you could run out of assist
before the vehicle is stopped.  When working on the brakes you are supposed
to pump the pedal till hard before working on the system.  Be a real bitch
to have your fingers between the pads and the damn thing apply the brakes.
Even a vehicle with vacuum brake booster should have 2 good pedal pumps
before running out of assist, and should not bleed all the way down over
night.
The power steering on the other hand, engine off, no assist.

Whitelightning