Brake issues - pedal feels soft

http://forums.justcommodores.com.au/680139-post6.html

 

yes, there is a way to change them without haveing to bleed the brakes but it doesn't involve the brake nipples

 

I don't know why you would need to open the bleed nipple. Once you touch that you need to redo your brake lines. You could have done it without touching the bleed valve.

Just undo the caliper at the bolts, remove old pads, use proper tool or two spanners to put caliper back in place, insert new pads, put caliper back on and your done. Just pump the pedal to make sure it engages.

 

The front calipers have two pistons, and you need to compress both of them simultaneously to force them back into the caliper to provide space for the new, thicker pad. My method is to use two G clamps.

1. Undo the lower caliper bolt and lift the caliper upto release the old pads.
2. Place the two G clamps over the caliper, one clamp to each piston.
3. Screw both clamps in to compress both pistons.
4. Remove both clamps, fit new pads to caliper mountng brackets, and lower caliper over pads onto bracket.
5 Reinstall lower bolt and tighten.
You do not need to touch the bleed valves, but you should check the level of the fluid in the reserviour to ensure it isn't over-full.

From your description, it sounds like you have air in the system. Only a full bleed will ensure that all air is purged. Follow the thread already indicated above.
When bleeding brakes, it is usual practice to start with the longer brake line first. As front and rear are separate circuits, do the passenger side caliper first on each circuit.

 

Agreed, definatly air in your lines. As you pushed the pistons back, did you keep the pressure on the pistons while you did the nipple back up. If you didnt then i would say you have sucked a small amount of air in each caliper. I would maybe try just cracking each nipple 1 by 1 as a helper keeps pressure on the brake pedal and just try to expel any air pockets in the top of the calipers and do the nipple back up quickly before the helper stops applying pressure to the pedal. You might get lucky and it will be a easy fix.

 

i crack the nipples when doing brakes at work, but i use a hose on the nipple to direct the fluid into our bleeding container to eliminate the chance of air getting in,

cracking the nipple is less fiddly, quicker, and makes doing 2 and 4 pot calipers much easier, it also eliminates the chance of the master cylinder over-filling and having brake fluid run down the engine bay paint

 

wrong post.....

 

sorry but if you dont understand how the braking system works you shouldnt be touching them.
next time at least get someone who knows what they are doing to watch you.

how would you feel if your brakes failed & you injured someone... or worse?

 

Oh god... 'Yes daddy':cry:

 

the main reason u crack the nipples is so that the brake fluid in the caliper is replaced.

 

correct, crap can build up in the pistons in the calipers, if you compress the piston the particles can be transfered through the lines back up into the master cylinder and abs system, which could cause blockages in the valves of the abs or cause damage to the cup seals in the master cyl.

of course this is a 'could happen' type of thing, but i crack the nipples at work all the time without and dramas thats of course if you know what your doing

 

did you place a tight fitting hose onto the nipple once you cracked it, the reason for this is to eliminate the problem you have, if the connection between the hose and nipple is sealed when you push the piston back the fluid will fill the hose, when you release the clamp, if the piston moves back out you will draw the fluid from the hose and not let air in,


when it comes down to it, everyone has different methods to doing procedures, this is how i do it, so thats how i wrote it,

 

say whatever you like, i stand by what i said, after all its common sense isnt it?


yes making mistakes is an excellent way to learn BUT not when it compromises the safety of yourself & others on the road.

i dont know any mechanics that open the bleeder nipple to push the pistons back as a matter of course.
putting a hose on it will certainly eliminate the problem.

& a special message to the fool with the "yes daddy" comment ...unless you have something constructive to say please dont bother