Topic: Bleeding the Brakes???

[Emodog04]

Ok here is my problem.  The piston wouldn't back off, full of dirt and grime. I cleaned that out.  everything is back together, but I can't bleed the brakes.  I think my bleeder valve has been rounded off or broken.  This is what it looks like, tell me if this is what it's suppose to look like.  It is almost fluch with the caliper and has a small hole in it.  Looks like to me someone has replaced the orignial with this.  There is no way to get it out without drilling it I dont think.  Any suggestions on how I could bleed the brakes without the bleeder valve?

[Bob Wessner]

I think my bleeder valve has been rounded off or broken.

I think you are right. It should protrude above the caliper body, quite a bit actually. You can still get new bleeder valves, I did recently for my 750. There is a cap for it that you can get also, or fashion one, it will keep water and debris out of the bleeder opening.

[Jim Shea]

At least you found a bleed nipple! I have searched on my front caliper on a 76 CB750 F1, and I am bug***ed if I can find it?

[Emodog04]

So does anyone have a suggestion on how to bleed without using the bleed valve?  I don't really have the tools at had to drill and tap the plug that has been placed there.

[Kixx007]

You are probably better off finding a new caliper.  Once you break off a bleeder screw in there its pretty much junked.  If it IS broken off, its likely because the prevous person to work on it, couldnt back the bleeder out.  Mine was stuck in pretty good, I heated it, soaked it in PB blaster, wrenched on it. Eventually after a few weeks of sitting I put the caliper in the vise, put the wrench on it, said a prayer, and told myself if it broke, I'll find a new caliper. It came out, but mine was not broke off.  Good luck.

[Emodog04]

I was riding the bike just 2 days ago and the brakes worked fine except for a squeek.  I should have left well enought alone.  But the bike has new pads that were installed just before I bought it so who ever installed these pads found away to bleed the brakes.  I am thinking about taking the line loose at the caliper and pumping untill I get fluid flowing and the using the actual line to release the air.  This could serve to just let more air in also.

[Jim Shea]

I was told that you don't necessarily have to bleed the brakes when you change the pads? Just that you may need a g clamp to push the pistons back to install the new pads?

[Emodog04]

Well I had to take the line loose to relase the pressure in order to push the piston back, thus air in the lines.  I don't know what else to do,  I may try finding a new caliper

[eldar]

Well if done carefully, you would not need to bleed. Open the cap on the master and push the piston in slowly. The fluid will go back up into the cup. Since you are not actually exposing the system to air, if you are careful, you should not have to bleed but you may need to remove excess fluid.

[Emodog04]

The problem I'm having there is that the piston is all the way in at this point, and I have no way of pushing it back out.  I think the fluid isn't actually going in to the caliper due to air.  I may try taking the line loose and pooring fluid directly into the caliper.

[Lee]

There really isn't any good way, that I know of, to properly bleed the brakes without a working bleeder valve. You've got air in the system now, so either you will have to repair the broken bleeder valve or replace the caliper.
Try an "Easy out" before you go shopping for another caliper. Any auto parts store should have them. Be careful of the cheap ones, the tip will snap off if your not careful. Get a good set if you can. They will pay for themselves after a couple of uses. If you can find one small enough to fit the existing hole. If you can, remove the caliper, disassemble and put in a bench vise. If no bench vise, you may have to do the operation while it’s attached to the bike. Either way, lightly tap in the "easy out", and give it a twist with the appropriate wrench. "PB Blaster" or "Liquid Wrench" may help.

If that doesn't work...the only reasonable course is to replace the caliper.

As far as pushing out the piston, reattach the line and try again. Even with air in the system, it should be enough to push out the pision.

[Emodog04]

Thanks alot Lee, those pictures where very helpful.

[hymodyne]

I've had good experiences with the squared-style extractors. they're usually sold right next to the type that were pictured in Lee' s post. my set of extractors paid for themselves in theri first use.

hym