Author Topic: Break leaking from pistons  (Read 1675 times)

Offline yozzer74

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Break leaking from pistons
« on: September 24, 2016, 04:41:22 PM »
Well I've fitted new seals in my calipers pistons were in good order just been in garage and all 3 are leaking why .I bought these calipers from eBay .

Offline hairygit

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Re: Break leaking from pistons
« Reply #1 on: September 24, 2016, 05:10:18 PM »
Did you thoroughly clean the grooves which the seals sit in? If they have the tiniest bit of crud in them they can leak. You say you bought the calipers from e bay, where did you get the seals? Reason I ask I've had a few from e bay over the years and they were rubbish. Only use genuine seals, brakes are safety critical, pattern parts are not worth the risk!
If it's got tits or wheels, it's hassle, if it's got both, RUN!!!

Offline yozzer74

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Re: Break leaking from pistons
« Reply #2 on: September 24, 2016, 08:13:03 PM »
I've used Honda parts on them they were very clean could the calipers be no good

Offline hairygit

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Re: Break leaking from pistons
« Reply #3 on: September 24, 2016, 08:33:28 PM »
Possibly, but unlikely all 3 would be knackered together, unless a previous owner has been careless cleaning them, using something seriously abrasive on the alloy, but I would think that unlikely. More of a possibility is incorrect pattern pistons, possibly supplied incorrectly or cost cutting!
If it's got tits or wheels, it's hassle, if it's got both, RUN!!!

Offline yozzer74

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Re: Break leaking from pistons
« Reply #4 on: September 26, 2016, 03:42:30 PM »
DON'T know what's going on with my breaks the seals don't appear to be leaking now .when I fitted the seals the day after they had leaked .so I wiped them clean .been 2 days now and they are still dry .any thoughts.

Offline Johnwebley

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Re: Break leaking from pistons
« Reply #5 on: September 26, 2016, 05:16:50 PM »
DON'T know what's going on with my breaks the seals don't appear to be leaking now .when I fitted the seals the day after they had leaked .so I wiped them clean .been 2 days now and they are still dry .any thoughts.



  have you used them ?


  pump the brake leaver to move the pistons,then use a C clamp to push the pistons back,
  a soft seal makes for a good brake system,
lifelong motorcycle rider,and fan

Offline MarkCR750

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Re: Break leaking from pistons
« Reply #6 on: September 26, 2016, 06:00:49 PM »
DON'T know what's going on with my breaks the seals don't appear to be leaking now .when I fitted the seals the day after they had leaked .so I wiped them clean .been 2 days now and they are still dry .any thoughts.

I had the same thing, new pistons , meticulously cleaned all of the original components, day after fitting one leaked, that was over a year ago and no leaks since, I put it down to residual oil I'd maybe not cleaned off the calliper/piston post assembly, hopefully yours will be the same.


  have you used them ?


  pump the brake leaver to move the pistons,then use a C clamp to push the pistons back,
  a soft seal makes for a good brake system,
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Offline yozzer74

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Re: Break leaking from pistons
« Reply #7 on: September 26, 2016, 10:18:12 PM »
No I haven't used them yet just pushed bike and pulled breaks .that's it .

 

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