Hi,
Obviously doing something wrong or something is faulty here:
1) Fitted KSPort front and rear
2) Replaced master cylinder with 929 for larger brakes
3) ABS unit is OK
4) Replaced all lines with copper/nickel lines
5) Bench bled master cylinder
6) Bleed brakes in correct order
No pressure build up at all can pump and pump and pump but nothing. System does not have any visible leaks.
So, I figured I would loop the connections at the master cylinder together to see if I can build up pressure just with the pedal and cylinder, but same result.
I am using the original reservoir of the old MC, can these things develop faults?
Thanks,
James
Is the pedal returning after applying pressure?. If the master cylinder was at fault i would expect it togo to the floor and stay there.
Seems strange the k sport brakes have they a bleed both sides of calipers? Wondering if you still have air in system.
Pedal returns back no problem.
Strange it doesn't build pressure even when the two circuits are blocked of the other connections near the MC.
It's bled multiple times and there;s no air coming out of the lines. I bleed the KSport on the outside nipple first, then inside on the caliper. Just curious why its the same problem even with all of the brake circuits blocked off.
Im not sure the MC is at fault as I first tried with the original MC, and thought the problem might be an undersized MC so I upgraded it to 929 anyway due to larger brakes, but fault still exists.
Reservoir is original though, can these go wrong in anyway?
Thanks!
reservoir is just that supplys fluid to MC...and as you have fluid at calipers with no air does not seem to be at fault.....strange.
Like you say closed ends should pressurise.
i had a similiar problem when replacing a front to rear brake just could not get a pedal and a mated suggested breaker bar on pedal and used seat to apply pressure. left overnight and voila.
but in this case with the closed ends does not make sense.
umm you pressurised with engine running so servo assisted?
Engines not running, so no vacuum assist. Can the brake booster fail to fully operate the push rod?
Im thinking at the moment, pedal play, or push rod clearance, maybe pedal is bottoming out before MC is bottoming out?
/J
Was it the same with the standard mc? Id run her up with servo assisting and see what it feels like.
Yea, same with standard MC. got some work to do before car will start, so not an option at the mo. I would have thought a badly operating booster would just make the pedal much harder?
Thanks,
James
Yes pedal would be hard....how does the pedal feel...travels all the way to stop? Then returns or goes hard but no pressure at calipers?
If the push rod was not operating on mc you would not be able to bleed....personally i alway manually bleed with 1 in car and me at nipple....always had fun and games with those ezi bleed systems.
If the brake pedal is very hard but no pressure at the calipers i think youve got to wait til car running as servo will amplify your foot pressure. My westy has no servo assist and i really have to push them hard and there tiny calipers as opposed to them huge k sports. Id personally wait til up and running and see if you still have a problem.
Pedal travels to a stop, then returns, can repeat over and over again with no build up of pressure, no resistance. Pedal is not firm, and does not change after pumping.
/J
Should go hard even without the servo...stuck myself now mate...ill run it by a mate tomoz. Master mechanic.
Cheers - any help appreciated.
/J
No worries...got all the symptoms of failed seal in the mc....but new and did it on std....perplexed!
I have a third (old) MC from a 92, probably original so I will give that a go.
If the problem is still present that could mean 3 broken MC seals, so that might make it less likley to be the MC.
Im going to try rebleeding the MC and then bleeding at each joint just incase it is air
But any other suggestions are more than welcome!
Cheers /J
I had a word with my mate and he said air or mc fault....did you try closed end with the original mc?
He also said slow movement on the pedal to protect the mc seals.
I had a word with my mate and he said air or mc fault....did you try closed end with the original mc?
He also said slow movement on the pedal to protect the mc seals.
I guess its possible i have been too rough with both damaged them both.
I will try the third tonight and be extra careful.
I will report later on tonight.
Thanks,
James
Sorry to hear your having issues,
With the greatest respect, are you sure the car is piped properly, we all miss things at times so it may be worth re-tracing the pipe work.
If its all OK it may help to invest in a Minivac.
I did when these first came out a few years back and swear by it to get rid of air locks that I have with four pots in the past., now I would never yuse anything else as it pulls the fluid out on a vacuum.
www.minivac.co.uk/brake-bleeding-kit
Hope this helps
I have invested in a power bleeder, so pressurizes the reservoir to force the fluid through, also means I don't have to go anywhere near the pedal.
When you say is it piped up properly, do you mean the right connections to the right points in and out of the ABS? or do you mean the physical runs?
The runs are not the same as stock (not quiet) so there could be some highpoints causing airlocks? Definitly no visible leaks.
Also, when the MC is isolated and blanked off its the same - no pressure.
At the moment Im thinking I have knackered both MC's (old one and a reconditioned one) by not being gentle enough during the bleed process. But I am also not ruling out pedal travel, as its all been disconnected I wonder if something has not gone back right in the mechanism.
Hello
Did you get the issue sorted? The fact you are having the issue even with a closed loop is baffling. If not I would have suggested to check the hose going to clutch master cylinder for leaks and check slave cylinder nipple is securly closed.
I will be doing the same as you in a few weeks with ksports front and rear so hoping I don't have this issue :/