TRD-Rob Posted April 16, 2016 Share Posted April 16, 2016 Can anyone help ? I've done a j-spec to uk break swop a while back and the pedal seems to have a lot of play I've checked the break servo and master cylinder and both seem to be working fine. Only thing that doesn't look right is the piston seems to be a bit far out. Quote Link to comment Share on other sites More sharing options...
TRD-Rob Posted April 16, 2016 Author Share Posted April 16, 2016 Quote Link to comment Share on other sites More sharing options...
Chris Wilson Posted April 16, 2016 Share Posted April 16, 2016 If you still have the stock rubber hoses clamp each one off near the caliper in turn. Be careful not to damage the hose, proper brake hose clamps are cheap. See if clamping one in particular brings the pedal back up. That's the caliper that may have air in it. How much pedal travel are you getting and how EXACTLY have you been bleeding the system? Quote Link to comment Share on other sites More sharing options...
Nic Posted April 16, 2016 Share Posted April 16, 2016 [ATTACH=CONFIG]211022[/ATTACH] I can't make sense of that pic, is that the caliper on a really small diameter disc? When you fitted the larger calipers you also fitted the larger discs as well? Quote Link to comment Share on other sites More sharing options...
TRD-Rob Posted April 16, 2016 Author Share Posted April 16, 2016 all four wheels off and bleed furthest away from master cylinder going closest to master cylinder,and doing it also with a break bleeder and also the old way with the pipe and pressure on the pedal Quote Link to comment Share on other sites More sharing options...
TRD-Rob Posted April 16, 2016 Author Share Posted April 16, 2016 I can't make sense of that pic, is that the caliper on a really small diameter disc? When you fitted the larger calipers you also fitted the larger discs as well? This is just what was in the kit,are the uk and j-spec two different thickness in disc ? Quote Link to comment Share on other sites More sharing options...
Nic Posted April 16, 2016 Share Posted April 16, 2016 This is just what was in the kit,are the uk and j-spec two different thickness in disc ? Sizes here http://www.mkivsupra.net/vbb/showthread.php?249089-Supra-Brake-setups Quote Link to comment Share on other sites More sharing options...
TRD-Rob Posted April 17, 2016 Author Share Posted April 17, 2016 Just looked at the disc and can confirm they are uks and having another look the piston don't look as far out,but still having a problem with the sinking. Quote Link to comment Share on other sites More sharing options...
Chris Wilson Posted April 17, 2016 Share Posted April 17, 2016 Please describe EXACTLY how you are manually bleeding. Have you tried clamping off some hoses yet? Quote Link to comment Share on other sites More sharing options...
TRD-Rob Posted April 17, 2016 Author Share Posted April 17, 2016 We have had all for wheels off and bled the breaks starting from furthest away,I start by pumping the peddle a couple of times then I hold pressure on the pedal whilst my mates cracks the bled nipple slightly to release any air,tightens up again once peddle is to the floor.we repeat 4-5 time on each corner. Can you please explain what clapping the hose off will do ? Quote Link to comment Share on other sites More sharing options...
Chris Wilson Posted April 17, 2016 Share Posted April 17, 2016 That's what I feared and is incorrect. NEVER have pressure in the system when you open a bleed nipple to do a manual bleed. Open the nipple one turn. have your helper SLOWLY press the pedal RIGHT DOWN to the floor. Have them hold it there whilst you tighten the nipple. have them SLOWLY release the pedal again. Repeat until no air exits. Do all four calipers. be sure to keep the reservoir topped WELL up whilst bleeding. If still there's air in the system try it with the ABS pump jumpered to continually run. I myself have never had to do this, but it's an option. Sometimes levering all the pistons right back into the calipers with the bleed nipple wide open will dislodge trapped air. Finally there's a chance the master cylinder seals and valves have had it. That's a strip, air line blow out, and rebuild with a repair kit job. Quote Link to comment Share on other sites More sharing options...
Dnk Posted April 17, 2016 Share Posted April 17, 2016 OPEN NIPPLE, DOWN PEDAL, CLOSE NIPPLE, UP PEDAL repeat till clear fluid in tube Quote Link to comment Share on other sites More sharing options...
pedrosixfour Posted April 17, 2016 Share Posted April 17, 2016 Don't forget that using a set of UK brake calipers on a car with a master cylinder designed for a set of small calipers will result in more pedal travel. Quote Link to comment Share on other sites More sharing options...
pedrosixfour Posted April 17, 2016 Share Posted April 17, 2016 I can't make sense of that pic, is that the caliper on a really small diameter disc? When you fitted the larger calipers you also fitted the larger discs as well? You're looking at the reflection of the outer half of the caliper in a pretty uniform & shiny disk with the part that is unbrushed by the pads being the small strip of rust. Rear face of the wheel spokes are to the right of picture. Quote Link to comment Share on other sites More sharing options...
TRD-Rob Posted April 17, 2016 Author Share Posted April 17, 2016 Retried this your way Chris and still no luck,think you might be right about it being the master cylinder,do you know if a uk one will fit the j-spec servo ? Quote Link to comment Share on other sites More sharing options...
pedrosixfour Posted April 17, 2016 Share Posted April 17, 2016 I'd expect it to. For whatever that is worth! Quote Link to comment Share on other sites More sharing options...
C12MMO Posted August 15, 2016 Share Posted August 15, 2016 Did you find a solution to this? Quote Link to comment Share on other sites More sharing options...
Chris Wilson Posted August 16, 2016 Share Posted August 16, 2016 The bleed nipple is at the top, isn't it? I have never tried but it may be possible to fit the calipers on the wrong sides of the car and end up with the bleed nipples at the bottom. And that won;t allow them to be bled properly.... Quote Link to comment Share on other sites More sharing options...
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