Brake Bleeding Help

AndUK · Unread post by **AndUK** » 22 Jun 2005, 14:37

From what I have read it seems that I need to have the suspension set to high with the road wheels hanging free before I bleed the brakes on my XM.
I don't know how I am going to do this at home.
Does it have to have all the road wheels hanging free?
Is there an easier way?
Thanks in advance

Unread post by **citroenxm** » 22 Jun 2005, 17:52

Use two axel stands or two jacks to hold the front up, Why does she need bleeding?? Have you had pipe work problems?? I think jacking is your only solution..

jeremy · Unread post by **jeremy** » 22 Jun 2005, 18:51

I don't think there is anything special about the front - just bleed in the normal way - I suppose if you can get at it properly you could always do it with the suspension raised but remember to prop the car up to ensure you survive the experience.
The back is slightly more difficult. The reason is that the back brakes are fed off the back suspension to provide for load compansation. The brake takeoff is after the height corrector and before the struts - so jack car up, height corrector shuts as the wheels drop and the suspension pressure drops as well so there may be insufficient pressure to bleed the brakes and in any event it would be purely the residual suspension pressure.
If you have the suspension set to full height the corrector is open and pressure is available.
Jeremy.
I expect someone will now tell me I've forgotten about some part of the electronics!

citronut · Unread post by **citronut** » 23 Jun 2005, 00:01

rear brakes are fed from dozer valve directly same as front but rear susp returns through dozer valve,that is why bxs always sit parked with rear end on deck when dozer valve seals are worn out,you will need to take rear wheels of to get to bleed niples,you will need car on high any way because when rihgt up it alows full presure to rear brakes regards malcolm

AndersDK · Unread post by **AndersDK** » 23 Jun 2005, 00:27

AndUK :
There is absolutely no demand for the wheels to hang freely when bleeding the brakes. I'd even say it is the opposite.
Like Malcolm writes above you need to set the suspension on high - <font color="red"><i>to get any REAR brakes pressure at all</i></font id="red">
Also it seems rather practical the suspension is at high - and then stiff - when you remove each wheel in turn to bleed here. Unless of course you want to lift the car on safety stands to get all brakes bled in one go.
Once you're ready to bleed - place a brick on the brake pedal - and the fluid will flow once the bleed nipple is opened. You may also clamp a piece of wood between drivers seat and brake pedal.
During the process it may be necessary to have the engine idle simply to have the HP pump running to keep up the hydraulics pressure for the brakes.
Look for AndUK's other thread with Q's on LHM & cleansecure capacities. We are in the process of shifting the fluid here - as a standard service measure [;)]
-

oilyspanner · Unread post by **oilyspanner** » 23 Jun 2005, 00:36

Another key point seems to be to bleed a LOT of LHM through, I fitted a long plastic pipe from the rear bleed nipple and ran it to the reservoir, it was quite a time before the offending bubbles came past.
Stewart

Unread post by **Richard Green** » 23 Jun 2005, 00:50

that's the correct way oillyspanner I have always used a long clear pipe and ran it back to the reservoir then you can depress the break peddle while engine is running and comfortably watch the bubbles come out.

AndUK · Unread post by **AndUK** » 23 Jun 2005, 01:23

Thanks everyone for your help, it's a great forum.
"citroenxm" asked why I was bleeding the brakes, well I am going to Hydraclean the system so I need all the help I can get.
Never done it before so that should be fun..............not.
AndUK