Offroad-Express

Hey, wat do I need to do to get rear disc brakes working,ive bleed them but pedal still spongey, is it the master cylinder?
Also any good trick in setting up hand brake cables/mounts etc I'm using nissan maxama calipers

you do have your calipers the right side?? the bleed valve should be at the top of the caliper sometimes you can have an air bubble in the porpotional valve...
As for your handbrake connection it depends on the vintage of the calipers some are real close with a little extention on the cable it'll work most require an extension angled piece welded to the arms on the calipers

Yep they up right way , sure I got out all bubbles, when I put vice grups on brake line after valve , brake pedal was hard and felt good , take it off and pedal goes soft, does hardern up when u pump it but stop and it goes soft

hamish4x4 wrote:Yep they up right way , sure I got out all bubbles, when I put vice grups on brake line after valve , brake pedal was hard and felt good , take it off and pedal goes soft, does hardern up when u pump it but stop and it goes soft

This indicates that you have either, air in the line after where you put the grips on, a leak after the grips, damaged rear hoses that are expanding when you put the brakes on, or excessive pad movement from resting to the rotor from either worn pads or over worn rotors.
perhaps

Near new pads , had rotors machined so all tight as brakes almost on.was going to have new brake lines made, but had used the nissan houses from calliper then some hilux ones to the tee just to get it working.not sure of problem

So... when you pump brakes up so hard, then keep pressure on pedal applied, does the pedal slowly go soft? If so, replace or service master cylinder

Yes think it went soft after pumping it up .i tryed getting it going 4 a hour or so, then decided I was running out of time so put drums back in as was going on a trip next day .y does it work fine with drums in.would I stick with same master cylinder or something else

So pedal dosn't go soft after pumping when drums are on??? Sorry, I was trying to be helpful but now I'm confused. Got to be air in system or your calipers aye

Works fine with drums in, are the master cylinders any different that run discs all round to discs and drums

I went to a Landcruiser master cylinder when I did my rear disc brake conversion. It is from an 80 series, so designed for discs all round rather than disc front and drum rear as the hilux master cylinder is designd for.
I got rid of my proportioning valve also.
It may help you to do a search of the site as all the info is on here about the swap.

Do the crusier master cylinders go straight in and plum up?

From memory they do, they are also an inch bore, which means they are pushing more fluid. This is the usual reason a disc conversion doesn't work as expected. It takes more cubic capacity to activate the caliper as opposed to a slave cylinder. By pumping the pedal you are forcing in more fluid so it will harden up. Sounds like there is problem elsewhere though as with the pedal pumped up, it shouldn't disappear with pressure maintained.
I had the same issue with mine (subaru calipers, their pistons are bigger again), but after swapping in heap of different masters I can't remember which one I ended up with.

hamish4x4 wrote:Do the crusier master cylinders go straight in and plum up?

Almost, you'll need to re bend the brake lines to get them to line up with the outlets, they may be on the opposite side to the Hilux/Surf ones.

Sweet cheers mate ,will c if can get hold of one