Bleeding brakes - does engine have to be running?

[rjkoop]

Probably a silly question but you guys have been pretty patience in the past so...

Does the car have to be running to bleed the brakes? I essentially drained most of the brake fluid because I rebuilt all 4 calipers. I want to fill up the brake fluid and bleed the brakes. The engine isn't 100% ready to start yet. Can I bleed the brakes without the car running? Just wasn't sure if the brake booster needed to be functioning when I do this. Or maybe I can use a brake bleeding vacuum kit to suck the fluid down to the calipers.

[81SPIDERMATT]

nope ... bleed away

[weekend warrior]

You don't need the engine running and a vacuum bleeder is a great way to do it without assistance, I've done it a couple of times this way.
Make sure you start at the calliper furthest away from master and finish with the closest, rear axle should be raised to bypass the compensator valve, and keep a close eye on the reservoir, the level can drop real quick!

[4uall]

does not have to be running

This might help, did this myself they sell them at Princess Auto

http://www.youtube.com/watch?v=L0oUejw5Edc

http://www.youtube.com/watch?v=MfTmlOZbXgs

Brake Bleeding in the Fiat 124 Spider:

Like many cars that use compensators to prevent lockup of the rear brakes under hard braking, the Fiat 124 Spider rear brakes must be bled with the rear axle supported. Otherwise, the compensator valve will fully close, and no fluid will be allowed to flow to the rear brakes.

On the 124, jack the rear of the car at the differential pumpkin. You can use a block of wood in between the jack and pumpkin to prevent damage. Place the jackstands as far outboard as possible on the rear axle tubes. Bleed the brakes farthest to closest (i.e. RR, LR, RF, LF) from the master cylinder.

Alternatively, if you choose, you can bleed the brakes with the car fully on the ground. Though, using this method, access is tricky and it takes nearly as long as jacking the car in the first place.

Note:Only get under a car that has been supported with jackstands; a jack alone is only meant to lift and can fail if holding a car up by itself.