brake bleeding

[shadrack]

anyone got any tips on bleeding brakes? fitted all new flexis and brake pipes tday as per mot fail sheet and its been a ba ard to bleed, weve bled it from each caliper working round and by the pedal travel i would say theres still air in the system. local non bmw garage says air is ost likely at abs unit and to bleed them there on the pipes where they enter and to bleed on the master cylinder, anyone have experience doing this and advice thanks

[amacman]

might be worthwhile investing in an eezi-bleed from halfords or accessory shop . follow instructions carefully especially regarding operating pressure and keep a watch on level .
after running half the bottle through have someone pump the pedal a dozen times to increase flow , all with the bleed valve open .
once the bottle is near empty ( with 2cm still in bottle ) close bleed valve .
repeat on all brakes . finally bleeding one brake manually to attain the correct fluid level in the master cylinder .
an old trick which worked on the original Mini with notoriously difficult to bleed brakes was to jam the brake pedal on overnight to pressurise the air out of the system causing the air to vent up to the master cylinder . air will escape slowly into the master cylinder when the brake is released .
if this is not successful you will need to have the system bled using diagnostics to cycle the abs pump .
air in the system can eventually work it`s own way out .

[X5Sport]

This article might help......

http://www.xoutpost.com/articles/x5/bra ... h-diy.html

For 'Power Bleed', read Eazi Bleed in the UK. I think ABS brake systems need to be pressure bled. But as has been said, watch the pressure as you can damage the ABS Modulator if you overdo it.

[Raj]

I had exactly the same problem when the X was overhauled earlier this year. We had all the calipers off to be redone but found there are a valves within the system that actually require the software/laptop to be able to open them. Ended up getting Jason to sort it.

[shadrack]

well had a good conversation with a newly opened indy to me (hes just resently parted from main dealer after 9 years and is 40miles closer than where i was going and 3miles from my work ) he said hes 99% (seen 5 x5s sent to him the same as mine) sure that what weve done is forced the seals on the master cylinder inside out from bleeding the brakes by pressing the pedal to the floor 100s of times, so ive ordered a new master cylinder (£55 motor fators) and he said to fit this and then bleed from the beging with the pressure bleeder which will take a fair bit of time! anyway today they have got alot worse with use but the fluid level is exactly the same so no leaks, he said that when the seals have been poped just the front calipers work. However when i asked to book it in with him he said it was a simple job for my bro who did all the new brake pipes and in his explanation he never menchioned anything about laptop for abs unit, last time we bled it running so the abs etc was powered up! also there is no abs brake function on inpa and it has everything else. i could be wrong and my brother is going to phone him when he does it. oh well get the e46 out for some fun!

[amacman]

once you have fitted the new master cylinder top it up to max with fluid slowly to allow air to rise .
it will need to be shaken gently and tap on the metal body with something soft to get out as much air as possible .
leave it for a while to settle before attempting to bleed the system .

[shadrack]

fitted new master cylinder, still no good, just been on inpa and there is a menu on the list titled: abs/dsc bleeding!!! so it wont let me into the menu so im taking it to the indy tomora and if he cant do it before saturday im booking it into stealers!

[Raj]

Sorry to hear the new master cylinder didn't do the trick. The symptoms you were describing we're exactly the same as what I experienced. The valves that allow the brake fluid to the rear brakes need to be opened to allow them to be bled. We went through 2 litres of fluid before we gave up and Jason sorted it by pressure bleeding with the valves released.

[nujon]

If, due to fluid loss, you have drained some/all of the fluid from the ABS pump/valve unit, you need to use TIS or suitable 3rd party software - to cycle the pump and valves whilst the brakes are being bled - no other way - otherwise you will find that you cannot bleed the rear brakes 'cos the solenoid valves to the rear calipers have closed. Good indies have the knowhow to sort this - cost me £50 recently for the exact same issue - don't go to BM - they will charge £££ just for the diagnostics then tell you you need a new ABS pump (which you almost certainly don't) at a cost of ~ £1000 + fitting

[shadrack]

yeh just to update, ive took it very carefully through to another indy i didnt know i was near, it was recommended by who i was dealing with! as luck would have it he has spare time to do it tmoro after he finished some cars tday that were suposed to go to tmoro. anyway he has seen it and recons it will take 30min to an hour using the software to cycle the abs pump, and he gave me a lift back 7 miles to the our yard so i could use a van to go home in!!! so far so good!

[nujon]

[quote=""shadrack""]yeh just to update, ive took it very carefully through to another indy i didnt know i was near, it was recommended by who i was dealing with! as luck would have it he has spare time to do it tmoro after he finished some cars tday that were suposed to go to tmoro. anyway he has seen it and recons it will take 30min to an hour using the software to cycle the abs pump, and he gave me a lift back 7 miles to the our yard so i could use a van to go home in!!! so far so good! [/quote]

Hope you get it sorted tomorrow - took my indy ~ 1hr - he repeated the bleed / ABS cycle sequence twice using 2.5 litres of DOT 4 in the process of getting all the air out. I noted that in the process, he always got his mechanic to open a bleed valve to before starting the pump sequence - and that the sequence was always stopped before re-closing the bleed valve - said to do otherwise can damage the ABS pump seals.

[shadrack]

yeh i hope it gets sorted to!!

[shadrack]

well got it back and they work fine.....but he pedal seems to travel more down tan it did before any of this started and seems sqishy/slow to come up, the indy said there is 100% no air in it now but the only thing it could be is that when my brother put the new master cylinder on he has missed a 'shim' which goes in somewhere between the master cylinder and the car? hes adament he missed nothing, anyone fitted one and know what this piece looks like so i can quiz my brother before the indy has to strip it again? i looked on real oem and cant find it, thanks