1. Attachments are working again! Check out this thread for more details and to report any other bugs.

which direction are the drum brake ratchets intended to turn?

Discussion in 'Gen 2 Prius Technical Discussion' started by prius_newb66, Feb 18, 2024.

  1. prius_newb66

    prius_newb66 Junior Member

    Joined:
    Mar 14, 2021
    60
    17
    0
    Location:
    Chicago
    Vehicle:
    2009 Prius
    Model:
    V
    I’m doing rear drum brakes and not sure if the previous owner may have swapped L and R hardware here — is it proper for rear driver side star ratchet thing to turn counter clockwise to tighten (if you are looking at front of the car from the rear)?

    That is, I have to push down the star ratchet thing from above for it to “click” and move the shoes outward — is this right?
     
  2. PriusCamper

    PriusCamper Senior Member

    Joined:
    Mar 3, 2012
    11,330
    4,614
    0
    Location:
    Pacific Northwest, USA
    Vehicle:
    2007 Prius
    Model:
    Two
    Maybe @ChapmanF or @SFO could offer assistance... I'd like to know myself because of some things I got planned...
     
  3. Mendel Leisk

    Mendel Leisk EGR Fanatic

    Joined:
    Oct 17, 2010
    56,671
    39,221
    80
    Location:
    Greater Vancouver, British Columbia, Canada
    Vehicle:
    2010 Prius
    Model:
    Touring
    Shows, last page in attached. Rotating star wheel with a downward motion unscrews it, increases the length of the adjuster bar, makes the brakes lock sooner.
     

    Attached Files:

    #3 Mendel Leisk, Feb 18, 2024
    Last edited: Feb 18, 2024
    Meg&Bear likes this.
  4. Tombukt2

    Tombukt2 Senior Member

    Joined:
    Nov 29, 2020
    10,372
    1,792
    0
    Location:
    Durham NC
    Vehicle:
    2009 Prius
    Model:
    Base
    From the back of the backing plate you lift up on the star wheel to widen the shoes to the drum I do believe that's correct been a long time since I've adjusted rear drums but I believe you use your brake spoon from the backing plate the little hole with the rubber plug which I've lost years ago You reaching with your spoon touch the star wheel and lift up with the spoon like your hoisting it to the sky You can't go back the other way without sticking a screwdriver in to move the locking mechanism to let you go down on the star wheel to loosen the shoes so the drum will come off please let me know if I'm wrong but I don't think so.
     
    Meg&Bear likes this.
  5. ChapmanF

    ChapmanF Senior Member

    Joined:
    Mar 30, 2008
    24,904
    16,213
    0
    Location:
    Indiana, USA
    Vehicle:
    2010 Prius
    Model:
    IV
    Each adjuster should get longer when you rotate its starwheel downward (at the point where the adjuster lever clicks over it).

    If one gets shorter when you do that, it's installed on the wrong side of the car.
     
    Meg&Bear and Mendel Leisk like this.
  6. prius_newb66

    prius_newb66 Junior Member

    Joined:
    Mar 14, 2021
    60
    17
    0
    Location:
    Chicago
    Vehicle:
    2009 Prius
    Model:
    V
    Sounds like the previous owner did fine and my new adjuster was mislabeled! It definitely said “Left Side” on the bag but the ratcheting machining is meant for the other side of the car — the adjuster from this bag, labelled Left Side, only makes the shoes wider when you “pull” it up (clockwise when looking towards the front of the car from the rear)
     
  7. mr_guy_mann

    mr_guy_mann Senior Member

    Joined:
    Sep 3, 2020
    3,668
    1,715
    0
    Location:
    NJ-USA
    Vehicle:
    2006 Prius
    Model:
    Four
  8. Tombukt2

    Tombukt2 Senior Member

    Joined:
    Nov 29, 2020
    10,372
    1,792
    0
    Location:
    Durham NC
    Vehicle:
    2009 Prius
    Model:
    Base
    Yeah me thanks from the back side of the wheel with the wheel on or off the rubber plug out you put the spoon in and lift up click click move the wheel here the drag click click a little more drag leave it alone other side same thing You get it too tight that's why you're only doing two clicks at a time like You get it too tight now you got to get a screwdriver in there to push the lock out of the way so you can back it up a couple clicks Don't be that guy.
     
  9. ChapmanF

    ChapmanF Senior Member

    Joined:
    Mar 30, 2008
    24,904
    16,213
    0
    Location:
    Indiana, USA
    Vehicle:
    2010 Prius
    Model:
    IV
    But before starting, you do have to make sure you have each adjuster on the side of the car it's made for.

    If not, instead of self-adjusting brakes, you have self-deadjusting brakes, and it doesn't matter what you do with the rubber plug or the spoon.
     
  10. prius_newb66

    prius_newb66 Junior Member

    Joined:
    Mar 14, 2021
    60
    17
    0
    Location:
    Chicago
    Vehicle:
    2009 Prius
    Model:
    V
    This is the entire point of my post. That's what I'm asking. The new brake hardware I got included a new adjuster for each side of the car, but the LH side was threaded in the opposite direction of the one that was currently ON the car so I wasn't sure which was correct. I thought, given the replies to this thread that what was on the car was correct but looking at this photo in the service manual I think now that maybe the previous owner put the wrong adjuster on the car.

    What I explained in my original post was that looking the the LH (driver's side in USA) drum from the tire side with the drum off (NOT from the adjusting port), I would have to push the adjuster ratchet DOWN (counter clockwise if you are standing behind the car) to get the shoes to EXPAND towards the drum surfaces. This seems to NOT be correct given the image I'm attaching from the service manual and it seems the brake hardware I got was correct and not mislabeled.

    The service manual image shows that the adjuster is turned DOWNWARD from the adjustment port behind the drum, which is clockwise if you are standing behind the car. I think people in the thread misunderstood me / I wasn't clear because this is not how the adjuster was setup when I took off the drum, but how it would have been setup if I put the new adjuster from the hardware kit labeled LH. I put the original adjuster back on but now I'm pretty sure that's not right so I wil have to open it again and replace with the adjuster from the hardware kit.
     

    Attached Files:

  11. ChapmanF

    ChapmanF Senior Member

    Joined:
    Mar 30, 2008
    24,904
    16,213
    0
    Location:
    Indiana, USA
    Vehicle:
    2010 Prius
    Model:
    IV
    It all comes to where the adjusting lever (the small spring-loaded steel lever attached to one shoe) contacts the star wheel. My memory was that the lever is on the outboard side (right in the open facing you when you've taken the drum off). The diagram you posted there does make it look as though the lever is on the inboard side (behind the adjuster, on the side toward the backing plate ... which is not the way I picture it, but I haven't been in there in a while).

    Anyway, that lever pushes the star wheel DOWN on whatever side it is. So if it's on the side I think, then your first description is correct, and if it's one the other side, your second description is correct. So just take a look at where that lever is.

    Edit: reviewing more diagrams for both Gen 2 and Gen 1, I'm convinced my memory was wrong and the lever is on the backing-plate side, so that's the side where you want a downward click to expand the adjuster.

    A diagram I had showing the lever on the outboard side was from a generic Toyota brake document, probably from some other model.
     
    #11 ChapmanF, Feb 20, 2024
    Last edited: Feb 20, 2024
    Mendel Leisk likes this.
  12. Tombukt2

    Tombukt2 Senior Member

    Joined:
    Nov 29, 2020
    10,372
    1,792
    0
    Location:
    Durham NC
    Vehicle:
    2009 Prius
    Model:
    Base
    Well I'll be adjusting the drums on my new '07 green car tomorrow afternoon I hope and I'll tell you right quick whether you lift up or push down with your brake spoon to tighten either side because today I changed the tires and I noticed that my shoes are not dragging in the drum properly probably never been adjusted so I will do that tomorrow which will change my braking drastically I'm sure this is the car that has all the lights on for the brakes It's not going to cure the problem by no stretch of the imagination but with this much shoe clearance in the back it certainly affecting breaking I know it does on my Corolla and I keep the shoes on the corolla's adjusted for a light drag and it makes a huge difference in breaking some of my Corollas are drum brakes not disc.
     
  13. prius_newb66

    prius_newb66 Junior Member

    Joined:
    Mar 14, 2021
    60
    17
    0
    Location:
    Chicago
    Vehicle:
    2009 Prius
    Model:
    V
    OK my brain is melting a little bit… right now I have a downward click for the LH (drivers side USA) adjuster when pushing on it from the access port side. Attaching photo of LH adjuster

    So, I guess this is correct? If so my brake hardware was mislabeled.

     

    Attached Files:

  14. ChapmanF

    ChapmanF Senior Member

    Joined:
    Mar 30, 2008
    24,904
    16,213
    0
    Location:
    Indiana, USA
    Vehicle:
    2010 Prius
    Model:
    IV
    Yup, that silvery lever in the middle is the adjusting lever, and there it is on the access-port side, so DOWN at that spot is what you want to mean "expand".
     
  15. Tombukt2

    Tombukt2 Senior Member

    Joined:
    Nov 29, 2020
    10,372
    1,792
    0
    Location:
    Durham NC
    Vehicle:
    2009 Prius
    Model:
    Base
    Yeah that's right so from the back side of that green spring you're lifting your brake spoon up if I'm not mistaking and the shoes are getting farther apart than hitting the drum if the drum is in place. Then to back that up you have to reach in and push that silver tab with a screwdriver so you can go the other way.
     
  16. mr_guy_mann

    mr_guy_mann Senior Member

    Joined:
    Sep 3, 2020
    3,668
    1,715
    0
    Location:
    NJ-USA
    Vehicle:
    2006 Prius
    Model:
    Four
    That image should be correct for the LH side.

    When there is "too much" slack in the shoe fit, the adjuster lever's "at rest" position is high enough to catch a tooth on the starwheel. The small vertical spring will pull the adjuster lever down as the wheel cylinder pushes the shoes away from each other. That lever will move the starwheel clockwise (from the rear) and make the adjuster longer.

    When the adjustment is correct, the lever can't move high enough to catch the next tooth on the starwheel so no further adjustment happens.

    Posted via the PriusChat mobile app.