4 replies to this topic

[jam2005]

Since I've fitted my MiniSport 4 pots I can't seem to be the brakes to bleed up properly. If been round all the brakes and I still can't get a pedal :nugget:

what happens is the brakes will bleed up if I keep pumping the pedal but 2-3 seonds later the pedal totally goes again. There are no leaks and the new calipers are fitted fine. Could it be the master cylinder seals? I here that it is a common prodlem with the seals flipping inside out. I so can I get new seals or do I need a new master cylinder?

Cheers, Jam2005 :grin:

[MRA]

Please don't think that I am taking the P*** I have seen this mistake and it is worth looking out for. :grin:

Check that the bleed screws are pointing upward ? If not then you have fitted the calipers on the wrong sides. :erm:

Secondly I would suggest that you invest in an "easy bleeder" this device pressurises the fluid and you stand a much better chance of removing all the air.

If you are able to "pump" up the brakes this suggests to me that the master cylinder is working ! :erm: by the way this is not good practice, as all you are doing is mixing fluid with air which gives crappy brakes and takes a while to dissipate out, thus making bleeding more difficult.

However if you have checked the rest of the system out (including any other valves) then to quote a famous detective - "however improbable, whatever is left must be the culprit) ok ok its nearly similar to old Holmes :grin:

[Guess-Works.com]

nuff said..... but the point about the calipers being handed should be taken note of.... seen it done :nugget:

[Jammy]

I take it you now know what type of brake system you have, and hence the correct order to bleed your brakes??

[dklawson]

You say they pump up OK but 2-3 seconds later they're soft again. Pay close attention to how the pedal behaves when you try that pumping.

If you pump 2-3 time (quickly) and you get a high pedal but it feels springy, make sure your calipers are right-side-up and that you have properly bled all the air out. You've put new brakes on the front... did you bleed ALL 4 wheels? If not, bleed all four wheels starting with the one furthest away from the master cylinder and work sequentially to the one closest to it.

If you pump the pedal 2-3 times and you get a firm, high pedal that isn't springy, readjust your rear brakes. No joke. You'd be surprised how much extra pedal travel you will have if the rear brakes are not properly adjusted. If your pedal is firm and high after pumping 2-3 times it's an indication that the first pump or two moved the shoes against the drums and the third is holding them in place. Without air in the system the pedal will be hard.