Mountain Bike Reviews Forum banner

Hayes bleeding trouble

585 Views 3 Replies 3 Participants Last post by  Ride On
HAPPY CHRISTMAS EVERYONE!

I'm having some problems bleeding my front Hayes Mag XC brake. I bleed them about every 3 months, and have done them heaps of times.

Now I've got a problem. I'm trying to bleed my front brake as it had some air in it and wasn't as powerful as in the past. I took out the bleed screw on the lever, rotated the lever so that it is up high, connected all the hoses and a syringe with brake fluid (dot 4) to the bleed nipple on the caliper, as per usual. There is heaps of resistance when I try to pump fluid through the line, to the extent that the syringe line blows off and sprays brake fluid everywhere. No fluid comes out of the bleed hole on the lever. I have bled the rear brake, and it is fine. Yet the front is impossible to bleed. When I open the bleed screw and the bleed nipple and then squeeze the lever, brake fluid comes out of the bleed nipple, so obviously the brake line is fine and not blocked at all.

Has anyone every had this issue before?

Any advice on how to solve it? I've consulted Zinns book and it doesn't offer any advice.

Thanks
1 - 4 of 4 Posts
rollsy98 said:
HAPPY CHRISTMAS EVERYONE!

I'm having some problems bleeding my front Hayes Mag XC brake. I bleed them about every 3 months, and have done them heaps of times.

Now I've got a problem. I'm trying to bleed my front brake as it had some air in it and wasn't as powerful as in the past. I took out the bleed screw on the lever, rotated the lever so that it is up high, connected all the hoses and a syringe with brake fluid (dot 4) to the bleed nipple on the caliper, as per usual. There is heaps of resistance when I try to pump fluid through the line, to the extent that the syringe line blows off and sprays brake fluid everywhere. No fluid comes out of the bleed hole on the lever. I have bled the rear brake, and it is fine. Yet the front is impossible to bleed. When I open the bleed screw and the bleed nipple and then squeeze the lever, brake fluid comes out of the bleed nipple, so obviously the brake line is fine and not blocked at all.

Has anyone every had this issue before?

Any advice on how to solve it? I've consulted Zinns book and it doesn't offer any advice.

Thanks
Hmmm... Try opening up the bleed nut on the caliper more?
Yeah, I've tried that one. Took the bleed nipple out completely and tried pumping brake fluid in from the master cylinder/ lever. Not a drop came through, which is why I'm a bit concerned. When I squeeze the lever with the bleed nipple out, old brake fluid sprays/ drops out, so obviously my brake line is ok.

I've also tried sorting it out problem by taking the brake off my bike and trying to bleed them horizontally on the bench to prime it and get some fluid into the line, but it won't go in!!!

I'm stumped, so any more advice would be great!
I had the same issue last season when I bled my rear brake. I could not get any fluid to move. I pumped so hard, the one piston ejected itself from the caliper and spewed fluid everywhere. Needless to say, I had to remove the caliper, and break it down, so i could properly install the piston again. Do yourself a favour and download the Hayes manual before you attemp a caliper rebuild, it comes in handy. Once I had it all back together, I had no issues with the bleed. so I'm assuming there must of been some crap in the system preventing flow. That said, I would suggest draining all your fluid first. Squeezing you lever lots to expell any old fluid, and making sure your pistons move freely in their bores, and are bottomed before the bleed procedure. Don't give up, eventually it'll go. Let us know what happens. ;)
1 - 4 of 4 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top