Brake fluid?

Discussion in 'Tech/Mech General' started by wizzer59, Mar 10, 2012.

  1. wizzer59

    wizzer59 Funster

    Joined:
    Apr 18, 2009
    Messages:
    2,882
    Likes Received:
    2,685
    Location:
    Englishman in Mid Wales
    Hi Guys have to change the brake fluid on my van, (1998 Boxer) Anyone know approx how much it will take?:thumb:
     
  2. pappajohn

    pappajohn Funster Life Member

    Joined:
    Aug 26, 2007
    Messages:
    29,461
    Likes Received:
    16,895
    Location:
    YO11 2BD
    i would say between 1/2 and 1ltr maximum inc the master cyl reservoir.

    more to the point..make sure you buy the correct DOT grade for your van.

    put the wrong one in and the seals could swell or deteriorate.

    it should state which grade in your vehicle handbook.
     
    • Like Like x 2
  3. wizzer59

    wizzer59 Funster

    Joined:
    Apr 18, 2009
    Messages:
    2,882
    Likes Received:
    2,685
    Location:
    Englishman in Mid Wales
    Thanks for that pappajohn, I had imagined it would be a lot more than that but that's good news, don't suppose you'd know the bleeding sequence (language Timothy) as well would you?:thumb:
     
  4. aba

    aba

    Joined:
    Oct 27, 2009
    Messages:
    2,793
    Likes Received:
    1,119
    Location:
    yorkshire
    personally i wouldn't bleed it using the brake pedal but use a pressure bleeder
    as the internals of the master cylinder can go rusty just beyond the normal travel of the pedal thus shredding the seals when pressing the pedal to the floor which would then require a new master cylinder.

    personally i would start with the shortest pipe from the master cylinder but using a pressure system i don't think its too much of a problem where you start.
     
    • Like Like x 1
  5. Geo

    Geo Trader - Funster

    Joined:
    Jul 29, 2007
    Messages:
    9,517
    Likes Received:
    5,572
    Location:
    Mansfield,Notts
    1. Syphon out as much old fluid as possible from the master cyl
    2. Re fill with new
    3. open one rear bleed nipple and allow to self drip through a tube into a jar about a 1/4 of a small jam jars worth
    5. Close nipple and do the next rear, same amount, close off and move to a front nipple
    Do each front nipple in turn allowing gravity to do its job,it may take a min or two to start flowing be patient, and top up master cyl after every wheel is done
    BUT LEAVE THE BLOODY PEDAL ALONE!!!!!!!
    We in the trade use this method on an almost daily basis without ever pressing the brake pedal, its simple plumbing there is no real specific order in which to bleed
    You will have clean fluid throughout no air and the best pedal you have ever had
    When we do come across a problem bleeder we clamp off one hose at a time till the pedal feels good than bleed that one only
    Using your brake pedal and master cylinder to bleed brakes is asking for trouble and risks damaging seals
    Drip Bleed (Gravity) OR Syphon bleed using correct equipment, pressure bleed equipment as a last resort, Pedal Bleeding--Never
    Geo
    Ps have a bleeding good time
    pps allow a couple or three drips without the tube before nipping up, air can not get in if fluid is coming out
     
    • Like Like x 6
  6. pappajohn

    pappajohn Funster Life Member

    Joined:
    Aug 26, 2007
    Messages:
    29,461
    Likes Received:
    16,895
    Location:
    YO11 2BD
    the quantity was only a guestimate but i very much doubt it would be more considering the diameter and length of the lines and internal size of cylinders/calipers....the master cylinder reservoir will take the largest amount.

    and Geo's already answered the sequence question. :thumb:
     
  7. wizzer59

    wizzer59 Funster

    Joined:
    Apr 18, 2009
    Messages:
    2,882
    Likes Received:
    2,685
    Location:
    Englishman in Mid Wales
    Thanks guys realy good advice for me as Ive always pedal bled:Doh:, will try your way first Geo and if it needs pressure then I'll get a pressure bleeder and try your way aba:thumb:
     
  8. dave newell lvs

    dave newell lvs Trader-Vehicle Services

    Joined:
    Oct 31, 2008
    Messages:
    2,513
    Likes Received:
    3,310
    Location:
    Telford, Shropshire
    When I replace brake fluid for customers I follow this sequence:

    start with the furthest from the master cylinder and open the bleed nipple with a tube attached feeding into a 1 litre jar.
    Connect a pressure bleeder (I use a Gunson's Easibleed) to the master cylinder and apply the required pressure. Gunsons Easibleed uses a spare tyre at max 20 psi as a pressure reservoir.
    When the tube is blowing bubbles vigorously into the jar of dirty fluid close off the nipple and repeat on the second furthest wheel from the master cylinder. Repeat this for all wheels moving from furthest to closest to master cylinder in order.

    You now have removed as much of the old fluid as is reasonably possible. Empty your jar.

    To refill with fresh fluid:
    Top up the master cylinder with clean fluid (DOT4), fill your easibleed bottle with clean fluid and connect it to the master cylinder and apply pressure from the spare tyre (check you still have 20psi first).

    starting at the furthest wheel from the MC again connect your tube in the jar and open the nipple, when fluid is running clean and bubble free close the nipple and repeat for the rest of the wheels moving in the same sequence as before, you will probably need to top up the fluid in the easibleed bottle.

    Once you have done all wheels try the pedal with the engine running, if it feels soggy I generally leave it alone for half an hour for any air bubbles to percolate up then do a final bleed with someone pressing the pedal manually for me.

    D.
     
    • Like Like x 1
  9. wizzer59

    wizzer59 Funster

    Joined:
    Apr 18, 2009
    Messages:
    2,882
    Likes Received:
    2,685
    Location:
    Englishman in Mid Wales
    Thanks Dave:thumb: would of happily paid you to do it but the old legs were tired:BigGrin:
     
  10. Geo

    Geo Trader - Funster

    Joined:
    Jul 29, 2007
    Messages:
    9,517
    Likes Received:
    5,572
    Location:
    Mansfield,Notts
    Far be it for me to even comment on another fellow traders methods let alone question
    them
    But seriously
    You take an air tight system, drain off all fluid, fill with air, then bleed:Eeek:
    I will never understand that logic Dave, and as you chose to post totally oposing advise i await your reply with interest there must be a valid reason :RollEyes:
    Each to there own i supose
    But it does now leave the original poster and others in somewhat of a quandary:Doh:
     
    • Like Like x 1
  11. dave newell lvs

    dave newell lvs Trader-Vehicle Services

    Joined:
    Oct 31, 2008
    Messages:
    2,513
    Likes Received:
    3,310
    Location:
    Telford, Shropshire
    I understand your point Geo but my reason is thus. Adding new fluid to old contaminates the new fluid. By pressure draining the old stuff out first you remove the chances of contamination and so give the new fluid a far better chance of staying good for longer. I used to use the new fluid to push the old stuff out but found I had to use twice as much fluid to get good clean stuff coming out of the bleed nipples.

    I've been doing it the way I described earlier for about three years now without any problems.

    D.
     
  12. Geo

    Geo Trader - Funster

    Joined:
    Jul 29, 2007
    Messages:
    9,517
    Likes Received:
    5,572
    Location:
    Mansfield,Notts
    You and others may have noticed that pressure bleeding was mentioned only as a last resort in my original post ,and there i belive lies the reason for your change to your present tactics, there are many and various reasons I don't use or recommend your present method, I wont go into them here as it may appear to some to be a game of one upmanship, it is certainly not that
    You might just out of interest try the drip/gravity method, it may half your time effort and material costs, because you are more familiar than most with hydraulic systems you, as we do, can work on all 4 wheels at once. I do not recommend novice or DIY to try4 wheels at once
    Were never too old to learn:Wink:
    Regards
    Geo
     
    • Like Like x 2
  13. dave newell lvs

    dave newell lvs Trader-Vehicle Services

    Joined:
    Oct 31, 2008
    Messages:
    2,513
    Likes Received:
    3,310
    Location:
    Telford, Shropshire
    We achieve the same ends via different means, I can live with that:Wink:

    D.
     
    • Like Like x 1
  14. vwalan

    vwalan Funster

    Joined:
    Sep 23, 2008
    Messages:
    7,594
    Likes Received:
    3,853
    Location:
    roche cornwall
    hi ,i usually suck the fluid through with a mitivac . just another way to do the same thing . i find on m,bike calipers the mitivac does the job really easy . never had a pressured system . but find the mitivac pump very usefull for allsorts .
     
    • Like Like x 1
  15. rainbow chasers

    rainbow chasers Read Only Funster

    Joined:
    Oct 30, 2009
    Messages:
    3,747
    Likes Received:
    1,720
    Location:
    Mid Cornwall
    Wont add anything regarding to bleeding, but one peice of advice I would give, is to replace the pipes from master cylinder back. The reason behind this is in the design. The brake pipes are clamped to the bulkhead just out of sight - the clamp holds dirt and grime, and is the weak point for rotting pipework. They can even pass an mot when corroded here, as you just cannot inspect it very well! Prevention better than cure, so if you are bleeding the system, may as well replace these pipes too!
     
  16. MikeD

    MikeD Funster

    Joined:
    Dec 21, 2011
    Messages:
    1,976
    Likes Received:
    1,759
    Location:
    London
    Brakes

    I also use the "geo" method and I would only add - use newly purchased brake fluid, probably DOT 4 or above and that you will notice when the older fluid is expelled when the cloudiness disappears as the fluid is replaced.
    MikeD
     
  17. pappajohn

    pappajohn Funster Life Member

    Joined:
    Aug 26, 2007
    Messages:
    29,461
    Likes Received:
    16,895
    Location:
    YO11 2BD
    agreed...never use that half tin of fluid you've had stored in the garage for ages...only from a sealed tin.

    brake fluid is hygroscopic (absorbs moisture from air) and if contaminated can cause the water in the fluid to boil under prolonged heavy braking resulting in a soft pedal and possible lack of brakes.
     
  18. Geo

    Geo Trader - Funster

    Joined:
    Jul 29, 2007
    Messages:
    9,517
    Likes Received:
    5,572
    Location:
    Mansfield,Notts
    OMG you have used the dreaded phrase:Eeek:
    The last time that was used
    I informed a guy about cleaning his black tanks and he thanked me, and also referred to it as the "Geo Method"
    Jim then got all sorts of grief from a guy in America accusing him of theft and copright breaches
    There is it appears a"GeoMethod" registered and copy writen in the States
    The chap has some software that scans the world web looking for use of the phrase to protect his Work/system
    he backed off when he was informed Geo was my name
    many have published his written work as their own and without any acknowledgement to him so he gets a bit touchy,and rightly so
    Sorry Jim Incoming:hardhat::hardhat::hardhat:eek:pp5:Rofl1::Rofl1::Rofl1:
     
    • Like Like x 1
  19. aba

    aba

    Joined:
    Oct 27, 2009
    Messages:
    2,793
    Likes Received:
    1,119
    Location:
    yorkshire
    i notice there is also a satellite tv channel called GEO it just seems all foreign to me but seems to be a world wide phenomenon.
    just dont let the fame go to your head:hardhat:
    :Rofl1::Rofl1::Rofl1::Rofl1::Rofl1:
     
Loading...

Share This Page