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How to FILL Avid Blakes from empty (not bleed)

coursemyhorsecoursemyhorse Posts: 192
edited September 2012 in MTB workshop & tech
I can find a million and one guides on how to bleed my Avid Juicy 3 brakes, but all of them assume that the brake system is already full with liquid and just has minimal air that needs to be removed via normal bleeding methods.
Can someone point me to a guide or tell/show me how to fill a system from totally empty. I have just serviced my Avid Juicy brakes internally and want to now refill them. Is it the same as bleeding? I don't think it can be, because the first part of a bleed normally is to bleed the caliper which just involves sucking air out at the caliper end.

To fill, do you pull or push the liquid through? From which end?

Cheers guys

Posts

  • nicklousenicklouse Posts: 50,675 Lives Here
    it is exactly the same but you will need a bit more fluid.

    on or off the bike? on the bike fill the lowerm syringe and push the fluid throughtill visable, then attach an empty syringe to the lever and continue pushing fluid throughand continue as for a bleed.
    "Do not follow where the path may lead, Go instead where there is no path, and Leave a Trail."
    Parktools :?:SheldonBrown
  • Yes I was going to do it whilst on the bike. I'm not sure I follow "push the fluid through till visible" ? Surely any pushing of the fluid into the caliper bleed port should be whilst a syringe is connected at the lever port as well, so the fluid can come out when it is all the way through?
  • Exactly, syringe with fluid on caliper, empty syringe attached to lever, push caliper syringe to purge fluid into system until it reaches lever syringe and starts to fill it up (make sure you have enough fluid in tr caliper syringe to push it through in one go)
  • ilovedirtilovedirt Posts: 5,798
    Exactly, syringe with fluid on caliper, empty syringe attached to lever, push caliper syringe to purge fluid into system until it reaches lever syringe and starts to fill it up (make sure you have enough fluid in tr caliper syringe to push it through in one go)
    You don't attach the syringe at the lever until the fluid is visible in the lever bleed port, otherwise there will be air in the system.
    Production Privee Shan

    B'Twin Triban 5
  • ilovedirt wrote:
    Exactly, syringe with fluid on caliper, empty syringe attached to lever, push caliper syringe to purge fluid into system until it reaches lever syringe and starts to fill it up (make sure you have enough fluid in tr caliper syringe to push it through in one go)
    You don't attach the syringe at the lever until the fluid is visible in the lever bleed port, otherwise there will be air in the system.


    I call BS :lol: There is no air into the system if you make sure the plunger is completely pushed in, any other air then is pushed upwards into the syring and bubble up to the top when the fluid starts to fill the top one, you do need to make sure you hold the syringe upright though. I bled my avids this way (iirc it's on the official avid vids too but i could be wrong) and had 0 issues
  • ilovedirtilovedirt Posts: 5,798
    The less air in the syringe when you do it the better - think about it, why would you bother attaching the syringe before the system is full of fluid anyway? All you're going to do is fill the syringe with air and make life harder for yourself.
    Production Privee Shan

    B'Twin Triban 5
  • nicklousenicklouse Posts: 50,675 Lives Here
    ilovedirt wrote:
    Exactly, syringe with fluid on caliper, empty syringe attached to lever, push caliper syringe to purge fluid into system until it reaches lever syringe and starts to fill it up (make sure you have enough fluid in tr caliper syringe to push it through in one go)
    You don't attach the syringe at the lever until the fluid is visible in the lever bleed port, otherwise there will be air in the system.


    I call BS :lol: There is no air into the system if you make sure the plunger is completely pushed in, any other air then is pushed upwards into the syring and bubble up to the top when the fluid starts to fill the top one, you do need to make sure you hold the syringe upright though. I bled my avids this way (iirc it's on the official avid vids too but i could be wrong) and had 0 issues
    The system is full of air. Dont attach the second syringe untill all the air is out or you will have too much in the top syringe causing issues. Just the same as bleeding them.
    "Do not follow where the path may lead, Go instead where there is no path, and Leave a Trail."
    Parktools :?:SheldonBrown
  • because it eliminates the chance of pissing fluid all over your bike. Additionally it stops you trying to mess around attaching a syringe afterward when you're trying to hold the first syringe upright to make sure the air bubbles at the top of that one don't get in the system. horse for courses I suppose. If the worse comes to the worst and the syringe fills with too much air, it will just pop the plunger out, this isn't so much of an issue as when you re-fit the plunger, you'll be pushing fluid from one to the other and the air won't get chance to put air into the system anyway.

    The way I do it may be 'wrong' according to how some do it. But it does work :) . Either way will end up with the same result
  • ilovedirtilovedirt Posts: 5,798
    What on earth do you do when you're bleeding your brakes? You have to attach both syringes somehow, it's not exactly difficult to do. And if you can't push a bit of fluid through your brakes without "pissing fluid all over your bike", then you probably shouldn't be touching them in the first place. Nick is right.
    Production Privee Shan

    B'Twin Triban 5
  • Like I say, you can do it either way. When i said 'pissing fluid' I may have been exaggerating and meaning 'spill a little'. When i'm bleeding my brakes these days, I use one syringe as i run Shimano on both my bikes. With regards to servicing of bikes, I am more than capable of everything service related that is a bit more than indexing gears (forks, shocks, brakes, etc). So thanks for your concern, but there won't be any 'i censored it up' threads coming from me :lol: (ok maybe if I start trying to build/true wheels as I have no skill in that department).
  • ilovedirtilovedirt Posts: 5,798
    Truing wheels is easier than bleeding brakes, take it from me!
    Production Privee Shan

    B'Twin Triban 5
  • ilovedirt wrote:
    Truing wheels is easier than bleeding brakes, take it from me!
    Wow it must be easy then since bleeding brakes (even avid) is the easiest thing i've ever done.
  • ilovedirtilovedirt Posts: 5,798
    I'm not great with brakes, but truing wheels is a doddle.
    Production Privee Shan

    B'Twin Triban 5
  • So if I am reading the above correctly you do it like:

    (With it all mounted on bike as normal)
    1: Fill syringe 1 with fluid. Degas it.
    2: Attach syringe 1 to caliper.
    3: Open fill/bleed port at lever.
    4: Push plunger of syringe 1 and hence the fluid up to lever.
    5: Wait for fluid to come out of lever port and wipe clean.
    6: Attach syringe 2 (empty) to lever port.
    7: Continue pushing fluid through into syringe?
    8: Now follow normal bleed procedure from this point onwards? i.e. from now onwards do a full bleed procedure as well?
  • nicklousenicklouse Posts: 50,675 Lives Here
    6 nope it needs some fluid in it. how much depends on what is in syringe 1.
    "Do not follow where the path may lead, Go instead where there is no path, and Leave a Trail."
    Parktools :?:SheldonBrown
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