Brake fluid change - hmmmm

[DaiRees]

So is there any special process to changing the fluid on these modern cars with ABS, I've only ever done in on old "standard" brake sytems.

My fluid is 5 and a half years old now

Also is there any way to know for sure when the new stuff is coming through, or do you have to rely on the "that must be enough" method?

i have abn "eezi-bleed" pneumatic bleed kit (you run it off a car tyre or compressor)i just run it with no fluid in and open a bleed nipple until no fluid comes out this shows me that there is no fluid in the line and only air, i repeat for all 4 wheels.
then i put fluid in the bleed kit and repeat the process but until fluid flows freely out of each nipple.
Job done ;). makes bleeding brakes a piece of cake and a one man job, just make sure that the fluid resevoir on the kit does not run out or you will just start pumping it full of air ;P

http://cgi.ebay.co.uk/EEZI-BLEED-BRAKE- ... dZViewItem

only cheap but an absolute godsend when bleeding awkward brakes
regards
Andy

I eventually got 'round to doing it

Now while I agree that the method old Malachy came up with above certainly ensures that the old fluid is completely replaced. I don't think I'd do it this way again. I reckon introducing air into the system is a mistake. I did the fluid change yesterday, then went for a test drive last night and the pedal was really soft . I bled it till bubble-free clear fluid was running from the nipples, but there must still have been some air in there. So today I bought another bottle of fluid and bled another half litre right through the system. I was surprised how many bubbles came out, and some of them travelled a long way!. Now I'm pretty sure that there's no air left in there, and the brakes feel fine.

Next time, I'd try to minimise the fluid in the reservoir before starting (by running the easi-bleed empty until the level is right), but them fill the reservoir and push the old fluid out with the new in the more traditional manner. That's gotta be less hassle.

[steve_earwig]

Haynes burbles on about not letting any air get into the ABS system because you'll need Pug to use a special piece of kit to get it out. It also says you can easily tell when the old fluid stops because it's invariably a different colour. Yeah, right, bollox. Mmm, I'm playing round my shiny pride and joy with what effectivly is paint stripper. Never again!

[jameslxdt]

i just hope you didnt activate the abs with the air in the system

[DaiRees]

i just hope you didnt activate the abs with the air in the system

Oh yeah did that.

[jameslxdt]

well i would like to point out then that there is probably air in the pump or stuck behind one of the valves, and if you trigger the abs now there is air in the system then the pedal will shoot to the floor

[DaiRees]

Nah it's alright mate, successfully tested it again since. Might have been a bit more careful last night driving 'round town and stamping on the anchors had I been aware of this possible outcome though

[jameslxdt]

there may still be air stuck in the pump as it hardly ever works and at town speeds it certainly wont be working

[DaiRees]

No I had the ABS going last night I mean, maybe 45 / 50 mph to standstill, it was fine.

When I say I activated the ABS with air in the system I mean after I'd done the job the first time, when there were still a few small bubbles in the pipes which came out with the second bleeding, not when it was empty.

You've got me all nervous now

[jameslunt]

i really would not reccomend pushing all of the old fluid out having an empty system at all!

it is better for the system to use twice as much fluid and time and not get any air into the system rather than try doing it cheaper and quicker by emptying and refilling.

did you bleed the clutch as well? If you were not aware this runs off the brake fluid res as well.

[mjb]

did you bleed the clutch as well? If you were not aware this runs off the brake fluid res as well.

On which model? Mine's its own "sealed" system...

[jameslunt]

on my d9 exec it runs from the brake res like most other manufactures use if yoiu have not got a cable opperated clutch. That way it saves them having to make 2 pots and physically fit 2 pots into the engine bay somewhere etc.

they use their own master cylinder but it still draws the fluid from the same place.

[DaiRees]

i really would not reccomend pushing all of the old fluid out having an empty system at all!

it is better for the system to use twice as much fluid and time and not get any air into the system rather than try doing it cheaper and quicker by emptying and refilling.

Yeah thanks for that - lesson learned I think! I'll never voluntarily introduce air into a hydraulic system again

did you bleed the clutch as well? If you were not aware this runs off the brake fluid res as well.

No the clutch is fine, I guess you'd have to operate it with the reservoir totally empty in order to get any air into that.

[jameslxdt]

did you bleed the clutch as well? If you were not aware this runs off the brake fluid res as well.

No the clutch is fine, I guess you'd have to operate it with the reservoir totally empty in order to get any air into that.

there is a one way valve on the clutch circuit so you can never introduce air into the clutch side when working on the brakes