Will my e-brake work if I lose hydraulic pressure?

[jfdid]

Just a quick question here guys, as the title states. On my 90 AWD, if I lost pressure in my lines(aka line burst), is the hand brake going to work still, or not? I haven't had the calipers apart on this vehicle yet. Thanks

 

[zephyr_8]

yes the hand brake will still work. It is a cable actuated brake so it doesnt matter whether there is fluid or not.

 

[jfdid]

THanks bud, i thought so, but I wasn't sure if it was totally mechanical or if it needed the fluid in the caliper.

 

[Omega]

All ebrakes are mechanicly operated.. any car, any continent.

 

[jtmcinder]

So, I guess those Jaguars with hydraulic ebrakes aren't cars.

- Jtoby

 

[Defiant]

So, I guess those Jaguars with hydraulic ebrakes aren't cars.

Christ, leave it to Jaguar. I'm only surprised the wunderboys at Mercedes didn't come up with such a jackass idea.

 

[Omega]

Well, mechanical or not, it runs independantly of the normal lines... i hope!

 

[defrag010]

It's false, your caliper won't squeeze the pad without fluid pressure.

Long story short, I was messing with my ebrake system when I put new cables in ( the stock ones were rusted), and I accidentally turned the e-brake lever on the caliper the wrong way and had it stick in the opposite direction as it would sit with the e-brake on. I couldn't get it to come back into place, so I figured I messed up the caliper. Later on, I was doing a brake change and when I took the caliper off, the lever slipped back into place and I could attatch the cable to it finally.
Well, after that brake job, I rebuilt both rear calipers and put new lines on, yadda yadda.. before I got a chance to bleed the brakes, I was going to test them out with the rearend up in the air by spinning the rear wheel and using the e-brake to stop it. When I pulled the e-brake, the wheel didn't stop and the caliper barely compressed at all. Shortly after, I bled the whole system, and without touching anything, the E-brake would now stop the turning wheel.

So, yeah, if the lines on each side of your rear blow up, you won't have e-brake.

 

[Defiant]

When I pulled the e-brake, the wheel didn't stop and the caliper barely compressed at all. Shortly after, I bled the whole system, and without touching anything, the E-brake would now stop the turning wheel.

As the pistons extend, they seize in place. When replacing pads, the pistons are retracted and you will have no brake at the pedal until they're pumped back almost against the disc.

You still have full ebrake without fluid, unless for some reason the rear pistons have been retracted. On a 2G, the ebrake is seperate mechanism.

 

[bjones18]

..... if I lost pressure in my lines(aka line burst), is the hand brake going to work still, or not? ....

Federal regulations (FMVSS) require motor vehicles have a secondary operated brake system incase of base system failure; i.e. your emergency brake must operate independant of your hydraulic system.

This does not mean your park/emergency brake works. Adjustment is required for the 2G drum-in-hat (DIH) e-brake; thru a hole in the brake rotor, followed by an adjustment at the hand grip. Procedure is in Haynes/Chilton or Service Manual.

 

[IHeartTurbo]

It's false, your caliper won't squeeze the pad without fluid pressure. [wrong]

Long story short, I was messing with my ebrake system when I put new cables in ( the stock ones were rusted), and I accidentally turned the e-brake lever on the caliper the wrong way and had it stick in the opposite direction as it would sit with the e-brake on. I couldn't get it to come back into place, so I figured I messed up the caliper. Later on, I was doing a brake change and when I took the caliper off, the lever slipped back into place and I could attatch the cable to it finally.
Well, after that brake job, I rebuilt both rear calipers and put new lines on, yadda yadda.. before I got a chance to bleed the brakes, I was going to test them out with the rearend up in the air by spinning the rear wheel and using the e-brake to stop it. When I pulled the e-brake, the wheel didn't stop and the caliper barely compressed at all. Shortly after, I bled the whole system, and without touching anything, the E-brake would now stop the turning wheel.

So, yeah, if the lines on each side of your rear blow up, you won't have e-brake.

Please leave. Now.

 

[Talesin]

On a related note, on a GSX, does the e-brake actuate all four calipers, or just the rear two? I've been told that usually an e-brake will only act on the non-drive wheels... of which there are none on an AWD car. Or was said friend talking out his posterior?

 

[bjones18]

If the 1g rear brake caliper has both, the emergency brake cable, and the hydraulic line going to it...this is called an integrated brake caliper. integrated calipers have a mechanism attached to the back side of the piston. This mechanism adjusts as pads wear for emergency brake operation.

If you actuate the cable mechanism on an integrated caliper, without a rotor between the pads, or if you replace worn pads with new ones you will have to turn the piston back into the caliper to fit it back over the rotor. Integrated calipers have notches in the piston face to turn it back into the caliper.

 

[zephyr_8]

postierer it is.. The gsxs only operate the rear calipers. Although your diffs may have an influence. Mine tend to lock hard enough that pulling the e-brake locks 3 wheels or so. But thats viscous couplers at work.

 

[bjones18]

On a related note, on a GSX, does the e-brake actuate all four calipers, or just the rear two? I've been told that usually an e-brake will only act on the non-drive wheels... of which there are none on an AWD car. Or was said friend talking out his posterior?

1. most e-brakes are on the rear.
2. 70% of your braking is accomplished with your front brakes (due to load transfer).
3. Front brakes are larger than rear brakes.
4. rear park brake actuation ends up being lower cost to manufacture.
5. Saab has Front e-brake actuation (or at least they used to).

 

[Defiant]

On a related note, on a GSX, does the e-brake actuate all four calipers, or just the rear two?

The actual brakes are on the rear discs on a 1G. However, with the (proper) DSM AWD scheme, locking any wheel will essentially lock all wheels through the marvel of the viscous coupling.
Interestingly, Chrysler used to work their emergency brake on the driveshaft. Rather a while ago, now.

 

[defrag010]

As I said in my first post, The rear Calipers on My car Will NOT stop the car VIA e-brake without fluid in them.

Then you'd better repair them. They're supposed to.

Closed.