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580K Slave Cylinders Leaking

Ed1 ยท 2019-08-12 12:51

Hey guys, I rebuilt both master cylinders awhile ago and was able to bleed the lines and they worked pretty good up till a week or so ago. The pedals got soft and eventually I completely lost all braking. I attempted to bleed the lines and was unable to. I even tried to vacuum pump the lines and wasn't able to get them hard again. I noticed oil on the outsides of the slave cylinders. It seems to be coming from under the dust cover. So I guess the seals are shot? Do they come out pretty easy? What's the process?

Replies10
  1. #1alrman2019-08-12 17:41

    You unbolt & remove the slave cylinders....... adjusting nut & locknut under the boot Hydraulic line at cylinder 2 x 9/16" bolts with small square plates that engage the large groove at the bottom of the slave cylinder clean the mating surface between the slave cylinder & brake housing & reseal with RTV when reinstalling.

  2. #2Ed12019-08-12 17:45

    10-4. When I do that am I going to get drenched in oil?

  3. #3alrman2019-08-12 18:03

    There will be some sitting in the cylinder & you should cap off the feed line or maybe clamp it off with some small vise grips - as long as the hose has not gone too hard, because you'll damage it.....

  4. #4Ed12019-08-12 18:09

    Awesome! I was just thinking, it's been almost a week since this money pit squirted oil all over me!

  5. #5Ed12019-08-13 09:39

    Hey Alrman, on the topic of seals, what's the process for replacing the backhoe control tower spool seals on top of the valve? I guess drop the spool out the bottom then pry them out?

  6. #6Coy Lancaster2019-08-13 16:25

    Not Alrman but yes you will have to drop spools out the bottom and replace seals and O-rings, top and bottom.

  7. #7Ed12019-08-13 16:36

    Haha, you'll do Coy! So do you just pry them out with a flat blade?

  8. #8Coy Lancaster2019-08-13 16:51

    The bottom ones will come out with the spool of course and you can use an O-ring pick for the upper ones. There is a dirt seal above the o-ring on each spool though.

  9. #9Ed12019-08-13 17:11

    That's what I meant, just pop out the dirt seal to get to the o-ring. I'm not worried about boogering them up, I ordered new ones.

  10. #10Coy Lancaster2019-08-13 17:27

    That's good