Bleeding Hayes Brakes

[project_d]

O.K., so I'm not new at this; I've bled Hayes brakes a dozen times or so. However, I'm having a problem this time. I had a kink in the line, so I cut the line (clean cut), put on new fittings, re-attach the line to the master cylinder, get it all nice and tight, give it fluid, tap the frame and lines to get air out, do the draw back, tighten everything up, blah, blah, blah.

So here's the thing: After I tighten everything down and seal the system, I give it a couple pumps, and it's not really engaging (it does ever so slightly, but not really). So I flip the master cylinder (brake lever) back up, take out the screw, and it looks like there's not enough fluid in there. So, I pump more fluid in from the caliper until, again, fluid starts coming out the top. I seal everything off again, give the lever a few pumps...it's not really engaging...I flip the lever back up...the whoe cycles goes like this again, again, again. I don't get it?

Anyways, I thought it was the master cylinder itself, so I grabbed a complete rear brake that I knew worked (at least it did last time I used it), cut down the line (cuz I need it for the front), and the same thing is happenning. So this would be VERY coincidental if there was a mechanical problem with these two brakes, but somehow, I don't think that's the problem. I can take an allen wrench to the adjuster screw and get it to where it finally engages, but the lever is waaay out there, and if I look in the master cylinder, it still looks like there's not enough fluid?!?!?

So my question is, can anybody read this and tell me what the problem is? Maybe I'm just pulling some bonehead move and forgetting to do "X", and although it's just a little thing, it's the reason for my problem. Any help is GREATLY appreciated.

Oh, the brakes were Comps and Mags...same problem.

Cheers

[thephat]

The lever should be slowly and evenly pulled a few times before the last push pull of fluid.

[project_d]

Originally Posted by thephat

The lever should be slowly and evenly pulled a few times before the last push pull of fluid.

Hey, how you healing up? I'm giving the lever a couple of short & quick taps to get the air out, then, leaving the lever alone and having no pressure on it, I pull the hose with the adapter out of the lever, then put the screw back in. This is how this part of the bleed was taught to me.

Should I not give it quick taps, but more even, slow, gentle pushes?

[uzziboy]

yes that is the trick pull slowly and let go slowly and give one more squeeze of the bottle make sure no air in fluid coming out of master and and tighten the bleed valve and then put screw back in master

[project_d]

Give one more squeeze after I let go of the lever, right? After having no problems for such a long time, I feel like I'm starting all over. Sorry about this guys (and gals).

[uzziboy]

yeah reaaaalllll eeasy i know how u feel i have new goodridge lines and have been putting off because of this very problem

[skate]

Maybe I can help.

It's kind of hard to follow what is happening from your description.

Lets see:
From what I read is that when you pull the lever it basically goes down all the way to the handlebar, unless you adjust the screw.


Are you using a bleed kit of some type or are you just doing the lever pull thing only?

[project_d]

Originally Posted by skate

Maybe I can help.

It's kind of hard to follow what is happening from your description.

Lets see:
From what I read is that when you pull the lever it basically goes down all the way to the handlebar, unless you adjust the screw.


Are you using a bleed kit of some type or are you just doing the lever pull thing only?

I'm using a bleed kit. After I do the bleed, and I've made sure that air is no longer coming out of the master cylinder, and the bleed screw located at the caliper is closed, and the screw in the master cylinder is tightened, I go to engage the brake, it's extremely squishy...pretty much comes all the way to the handlebar. Then, when I take out the screw from the master cylinder, it looks like there's a bunch of air in it. So, I pump more fluid in from the caliper.

This whole process repeats itself over and over. It's almost like air is coming into the line somehow, or I'm not getting all the air out, but I don't see how. I've looked all over the line and fittings, and it does not appear that fluid is leaking from any place.

[skate]

Originally Posted by project_d

I'm using a bleed kit. After I do the bleed, and I've made sure that air is no longer coming out of the master cylinder, and the bleed screw located at the caliper is closed, and the screw in the master cylinder is tightened, I go to engage the brake, it's extremely squishy...pretty much comes all the way to the handlebar. Then, when I take out the screw from the master cylinder, it looks like there's a bunch of air in it. So, I pump more fluid in from the caliper.

This whole process repeats itself over and over. It's almost like air is coming into the line somehow, or I'm not getting all the air out, but I don't see how. I've looked all over the line and fittings, and it does not appear that fluid is leaking from any place.

Here's what you can do.

I'm glad you have a bleed kit. for a minute there I thought you were just doing some type of gravity bleed.

Anyways. The reason you're getting the air in the system feel is because of your brake lines. When you compress your lever your lines basically expand. Giving it the extra pull. This is why braided line are are popular because when you pull the lever it doesn't expand; therefore, stops exacty at a certain point instead of getting the little extra pull.

Now to fix your problem.

1. bleed your brake as normal.
2. once you know there isn't anymore air in the line. close the master cylinder.
3. Now make sure that the bottle or syringe is still placed on the caliper, when you close the screw on the master cylinder.
4. With the dot fluid still in the bottle and/or syringe and still placed on the caliper squeeze more fluid into the line.
5. at this point its like your bleeding the line, but with the top covered.
6. once you have added the extra fluid close the screw at the caliper and pull the bottle/syringe off.

once you do this you will have to play with it because it may be possible that it may be to stiff. or in a sense to much fluid.

if that is the case the best thing to do is repeat the steps and get a feel for how much extra to add.

Give this a shot. i do this trick with all my brakes hayes or not, and my friends brakes. so i'm hoping it will work for you also.

[jruiz]

the first thing i usually do is back off the screw that adjusts the reach , do a normal bleed, screw in the reach adjustment knob. WORKS ALL THE TIME FOR ME ON HFX9S

[project_d]

Originally Posted by skate

With the dot fluid still in the bottle and/or syringe and still placed on the caliper squeeze more fluid into the line....

I don't think this "fixed" the problem, but it worked anyways. Thanks!!!