no rear brakes

[Tommo560]

just put 280Z rears on the car and bled the system but the pedal is really soft to about 5/6 of the way down and the rear brakes dont work. The fronts seem to work fine but the rears aren't working at all, but when you open the bleeder nipple and push the pedal brake fluid comes out. just rebuilt the calipers did i perhaps put them together wrong?

anyone dealt with this and know what the problem might be? i am supposed to be racing the car tomorrow but cant at the moment.

Thanks,

Tom.

[LanceM]

I would start with bleeding the master and going back, an air bubble in the master will do that and getting it out trying to bleed the system is almost impossable.

[Darrel]

Did you adjust the rear brakes?

bleed screws go on the top of the calipers.

[beandip]

Did you adjust the rear brakes?

bleed screws go on the top of the calipers.

Darrel may have nailed the problem with the bleed screws statement. Also did you change the master to a compatible size unit . that is if you went to disks in the rear instead of drums . Check this out , you may need to be using a master with larger volume piston for the calipers in the rear . Just a thought . Gary

[Mat M]

Did the master ever run out of fluid during the caliper swap? Maybe the master needs to be bench bled?

[Tommo560]

Bled the master already and that wasn't it.

forum was down when i last checked so i just went ahead and pulled the calipers apart again and found that something with the back of the piston had frozen, so fixed that and hopefully we should be good to go.

As for the master size a friend has the same setup and has the standard master and has no problems, so unless it is a big issue i probably will just leave it standard.

Thanks for the advice,

Tom.

[beandip]

Bled the master already and that wasn't it.

forum was down when i last checked so i just went ahead and pulled the calipers apart again and found that something with the back of the piston had frozen, so fixed that and hopefully we should be good to go.

As for the master size a friend has the same setup and has the standard master and has no problems, so unless it is a big issue i probably will just leave it standard.

Thanks for the advice,

Tom.

That was just a thought in case all else failed you as well as a possibility. If you know someone that has the same set up and it works well then don't vary from it.

[Tommo560]

Still dont work. well thats the weekends racing over, ahwell too bad.

anyway beginning to think that its the master cause everything else is fine. did a bit more reading on here and hybridz and found that the stock master has trouble powering the toyota 4x4 a rear drums, so the fact that it now has big Holden 2 pots (HUGE) and rear disks and that only the fronts work (dont know how well haven't road tested but they do stop when pushed by hand) i am led to believe that the master just can't supply enough pressure to the brakes.

Tom.

[Darrel]

What exactly is your brake set up front and back?

[Tommo560]

ok all fixed.

despite my dads best assurances the problem was that the bleeder nipple wasn't actually at the top of the caliper. so we took the calipers off, angled the nipple to the top and bled them and a HUGE amount of air came out, so that solved that problem.

Brakes are Ford BA XR8 falcon vented 2-spot fronts and solid 280zx 1-spot rears, which is a phenomenal inprovement over drums and the hilux 4x4 brakes.

We finally finished at 8.30pm on saturday and then traveled to the hillclimb where we arrived at 12.00am at the caravan park where we were staying the night. Raced up the hill the next day everything worked fine and i even managed to beat my dads time by 4 seconds (he was in the zed too) and take out the class (ahead of my dad in the z and a BMW M coupe) for my first ever win at a hillclimb with a time only 6 seconds off the pace of the wrx's and only 4 seconds slower than a mate in his supra. so it was a hecktic day/night on saturday but worth the trouble.

Thanks again for all your help, we would never have got it going if we hadn't known to turn the nipple so it could bleed better than on the car.

If its not too much of a problem i do now have something that has just come up. we have found that the rear right brake is dragging a bit. haven't done anything differant to the other side of the car and i can't seem to figure out what it is. i remember reading that there is some sort of valve in the master for the rear drum brakes that could cause the disks to drag after a conversion, is this it? if it is why is only one brake dragging? i will probably be swithching over to a 280zx master and proportioning valve anyway sometime soon so should i even bother with fidling with it?

Tom.

[Darrel]

Turn the bleeder or swap the calipers from one side to the other?

Glad you got it all sorted out.