today my friend and i go to change my rear brakes. we get the calipers off, and get the new pads in there, but then cant push the pistton in to fit the new pads (we didnt have a C clamp) so we put the odl pads back in and reconect everything and decide to do the job tommorow, when i drive away, the brakes dont work at all. the pedal goes to teh floor and only puts a slight bit of resistance on the rotors. during the job, my friend accidently disconnected the main brake lin eon the calpier spilling a lot a brake fluid, but there was still a little more than half of the fluid left in the container under the hood. during the job we had only disconnected one of the calipers (back right). anyone have any idea why the brakes dont work? is having about half the brake fluid out enough to make them not work? thanks.

 

How much fluid was lost? Is the master cylinder resevoir emptied? By main brake line I assume you mean you removed the banjo bolt connecting the flexible hose to the caliper? You were just changing the pads...why the hell did you unscrew that bolt? Did you release the pedal with the line disconnected? If so, you probably sucked a ton of air into the brake lines. And don't use a C clamp on the rear brakes. Please don't try to work on your brakes anymore. Get a shop, and sit on your hands until he gets there so you don't hurt yourself.

 

that's exactly what happened to me couple days ago. i bet your brake light came up even after you push down the e-brake and refilled the brake fluid. but i was polishing my brake assembly.

i'm gonna have my friend help me press down the brake pedal, and leak out all the brake fluid, and then tighen the brake line, then refill the brake fluid, then release the brake pedal. and that will push out all the air in the brake line.

 

haha i just had this problem last weekend. the rear brakes on the maxima you have to twist the piston counterclockwise to get it to go in. and if it doesnt, your caliper is probably frozen, which is what happened to my car. now it's sitting at home while im here at college so i'll have to fix it later (need to replace rear pads, rotors, and calipers). =(

 

the master clyinder is only about half full now. i never pushed down on teh brake pedal after the flexible hose was disconnected, we never pressed on the pedal at all during the job.


so to get the piston to go in, all you do is turn it counter clockwise and it screws in?

 

Turn clockwise. Push in at the same time.
The master cylinder? If the master cylinder is only half full of brake fluid, then the other half is full of air. Refill, and bleed. You know how to bleed, right? Don't unscrew the banjo bolt again. Use the bleeder screw. Or do you mean the master cylinder resevoir? It's the semi clear looking bottle on top of the master. 1/2 full is normal. Do you see the min and max lines on the resevoir? Fluid level should be between those two. Once you've bled the brakes, try again. If the pedal is still like that, then have your friend press it again while you have the wheel off and you're watching the caliper. Look for leaks. Did you screw in the banjo bolt all the way? Try to learn more about your brakes. Otherwise It's best to just leave it to a pro. It's the only thing on the car that'll kill you if you mess it up and drive.

 

ok i got all the new pads in.


the master cylinder resevoir is half full, about an inch under the MAX line. how do i bleed the brakes? do you just take off the rubber nipple on the bleeder screw or take the entire screw out?

 

First of all, like it was mentioned earlier the rear caliper piston needs to be turned so it can be retracted. Here is the tool you should use for that.Disk brake piston tool #KD3162 Third one from the top. It's not too expensive, that web site sells it for $9.92. You should be able to find it at your local parts store. If you see the it looks like a cube. Look at the rectangle box that has 6 patterns. These patterns are the different types of piston faces this tool can be used on. The holes are for putting the rachet in, like a socket.
Secondly the reason why your brakes don't work is because air was let in the system when the fluid came out.

 

i was able to get the pistons pushed in with needlenose pliers and got the new pads in. i also found how to bleed the brakes, but before i do it i have a couple questions on that;


i only let air into one of the calipers, do i only need to bleed that one line (back right)? or do i need to do all 4?

also, when bleeding the line does the cap of the master cylinder resevior have to be on or off? thanks.

 

Yeah that counterclockwise advise could have ruined a lot of people's rears.

I got this set for $32, I think it's worth it over the KD. Plus say your friend has a Boxster S where the piston is not only on one side, this kit will get the job done. Brakes are so easy on the max. Airbags are not!

$32 took kit

 

1) It is recommended that you bleed the whole system(all 4).
2) I'm not sure it would really make a difference if you bleed the brakes with the top on or off. But, brake oil absorbs moister, so you should not leave the reservoir top off for more time than necessary. Moister os no good for brake systems.