Juicy 5 lever leak

MountainPete

I've had my Avid Juicy 5's for about two and a half years now. They've been good reliable brakes and I've only bled them a couple of times.

A couple of months ago I noticed that there was a dribble of brake fluid coming from a small hole in the black back plate of the lever assembly (I can only assume its main use is for air to escape the system via a diaphragm). I decided to bleed both brakes and see if there was loads of air in either - there wasn't.

Now I have noticed that there is some fluid (it's noticable from a 'damp' patch on the black) seeping from the join of this black back plate to the lever assy (the red line in the picture at the bottom shows exactly where). I've just had to push the pistons in and there was a much more noticable dribble of fluid coming from here.

I have not noticed any reduction in braking power.

Are these leaks a result of me putting too much fluid into the brakes when I've bled them? Or are the seals gone?

And do I now:

a) Forget the leaks
b) Replace the seals
c) Get new brakes

Bit of a long one, but thanks for reading if you've got this far!

nicklouse

tighten up the cap bolts.

MountainPete

Sorry Nick, forgot to mention - I've done that too.

MountainPete

Just tried tightening them again and they definitely won't go any further! Still a bit of a leak though. Any more suggestions?

nicklouse

leave it for some time.

all there is there is the diaphragm and if there has been some fluid on the wrongs side it will take some time for it to evaporate or "leak" out of the breather hole. it can then track down the seal joint.

if the brakes feel fine and there are no drips dont worry.

MountainPete

Thanks Nick!

nicklouse wrote:

...and there are no drips dont worry.

There are drips coming from the hole on the back though. Not very frequently (if I leave the bike alone for a few days there will be a drip that's slid down onto my gear shifter) but after a ride there is also usually one that's worked its way out...

nicklouse

if you are worried remove the lever and pop the top off and look. when put back together you may have some air under the seal so a quick bit of syringe action on the lever end can help remove that air.

MountainPete

OK thanks again Nick - I'll see what happens!

MountainPete

Sorry to drag this thread up again!

My forks have been off for a service this past week so my bike has been out of use on a workstand for the duration. The forks are back in but I noticed more leaked fluid from the front lever and a certain loss of power. They still stop me, but the rear is definitely more assertive.

What's the next step?

nicklouse

how far did you get?

i would order a new diaphragm and then have a look.

but you say

There are drips coming from the hole on the back though

pics of this hole?

is it the other bleed port? tighten it.

so far all the leaks seem to be reservoir side so nothing to do with braking performance. the fact you have re fitted them will be the need to bed in again reducing the power.

MountainPete

I'll do a few more full stops too and make sure everything is tight again (although I'm sure that all the bolts are as tight as they can get!)

The small hole is on both backing plates, close to the centre. Pictures will be a while I'm afraid as I'm not with both bike and camera for over a week now!

nicklouse

right that sounds like the breather hole

MountainPete

That's what I guessed it was, although it's now got a dribble!

nicklouse

it has been on the work bench the other way up and it is just moving again?

like i said if you are worried get a new diaphragm just in case and have a look.

MountainPete

It hasn't been upside down, but it hasn't been in its normal position as the handlebars have been off - perhaps that's the reason.