Trying to Bleed Front Brake

[Anonymous]

Hi Guys,
I figured I would change the front brake fluid on my bike but now I can't get the new stuff to flow into the system I've tried pouring it into the caliper and filling the reservoir with no luck. Today I tried to push the stuff through the system with a syringe but that isn't working either. I am not getting any pressure at all when I pull the lever and I only get a drip come out the other end! What the heck should I do about this?

Thanks, Steve

[redliner1973]

Did you completely drain the system then put fluid into it, or did you 'bleed' the brakes whilst continuing to replentish the fluid until it came out clear? If you completely drained it first, it sounds like you have either a blockage in the system, or your master cylinder is not bleeding itself. i would first disconnect all the brake likes, and blow through them to assure they are not blocked. 2nd, crap in the lines often settles down right at the bleeder screw, this has happened to me on more than one brake job. you may have to remove the bleeder screw, make sure it is clear, and if all that doesn't work, post back and well see where to go from there..hope that helps.

[Anonymous]

I AGREE WITH TIM, YOU MIGHT ALSO WANT TO TRY THIS, FILL THE RESOVOIR WITH BRAKE FLUID AND PUT THE COVER BACK ON, PUT PRESSURE ON THE SYSTEM BY PULLING THE BRAKE LEVER UNTIL IT STARTS TO HARDEN UP, PROPABLY, THREE OR FOUR TIMES, WHILE HOLDING THE BRAKE LEVER IN LOOSEN THE BLEEDER SCREWS, BUT DONT' LET GO OF THE LEVER UNTIL YOU TIGHTEN THE BLEEDER SCREWS AFTER THE LEVER HAS GONE IN AS FAR AS IT WILL GO. TRY THIS A COUPLE OF TIMES UNTIL ALL THE AIR IS OUT, MAKE SURE THAT YOU HAVE A HOSE ON THE BLEEDER SCREWS BECAUSE BRAKE FLUID WILL MAKE A BIG MESS OF PAINTED CALIPURS, TRUST ME I KNOW.

[Anonymous]

I've got the method of bleeding brakes down but it just isn't working in this case. It must be the master cylinder being full of air because I did drain the system before trying to fill it again. I did remove the hose at the caliper and clean out the screw too.

Steve

[Anonymous]

try this

Hi, I had this same problem. There may be a big pocket of air up by the master cylinder. After determining that the lines are not blocked. close the bleader valve. loosen the banjo bolt up at the master, and re-tighten just enough so it dosen't leak. keeping the wench on the banjo bolt, with a rag around it, pump the break, hold it in & "crack" the banjo bolt re tighting right away. you should get a splat of air & fluid. repeat this a few times till you get only fluid. you should now get pressure and will be able to blead the system as usual.

[Billy Ricks]

I agree with Karl. You may need to get the master cylinder primed again.

[Anonymous]

bleeding brakes

My answer is pretty much the same., but you can apply this method all the way down the brake line. So.

1. Fill the resevoir and make sure fluid comes out of the banjo, then tighten it.

2. Remove the banjo on the brake caliper and pump the brake lever until fluid comes out, keeping the fluid topped up at all times. When you release the brake lever slowly, cover the end of the hose with your thumb. It won't stop all the air getting back in, but its enough.

3. Attach the hose back onto the brake caliper and blead each nipple one at a time until flui comes out of each.

4. When you have got some pressure in the system, tie your brake lever back as far as it will go and leave it over night. Any trapped air WILL eventually rise to the top.

5. Next day, slowly release the brake lever and pump it a few times. See if the system has developed more pressure. If so (and it should have), tie the handle back again and leave over night.

This method took me a whole week but it was the only way I managed to bleed the system succesfully. If you can't bleed it in the usual manner then try my why.

Good luck

[Anonymous]

I missed out one point in my previous answer. If you do tie the brake lever back over night, leave the cover off the resevoir.

Good luck

[Anonymous]

Ugh, no luck so far with my brakes. If I disconnect the line from the master cylinder I can prime it but by the time I reconnect the hose I lose the prime. I guess I'll let it sit around all weekend with the lever held in but I'm going to leave the reservoir covered up since the bike is outside. Any more ideas guys? I can't believe I'm having a problem with such a stupid thing as this. It should work, how does the factory do it?

Thanks again, Steve

[Billy Ricks]

There is a pressure relief hole in the master cylinder that may be causing your grief. If it is clogged it may not be allowing fluid to go through the system. It shouldn't have any effect, but who knows. It is there to relieve pressure after the brakes have been released so the pads pull back.

[Anonymous]

OK. If there is no pressure in the system, leaving the brake lever pulled back will have no effect, you must build up pressure first. So, don't disconnect the hose from the resevior, just disconnect it from the caliper. Pump the lever and observe fluid coming out the bottom of the hose. Next, reconnect it to the caliper, then remove one bleed nipple. Pump until fluid appears with no air bubbles. Repeat for the other bleed nipple. Then repeat for the other caliper. REMEMBER. Pump the handle - release the bleed nipple - close the bleed nipple - slowly release the lever - repeat. This can be very time consuming so be patient.

[Anonymous]

The Solution, Finally!!!!
My bike wont bleed out the brakes unless I have the handlebars cranked to the left. Why? There are two holes in the bottom of the reservoir but one is covered by a piece of plastic. This plastic part won't allow air bubbles to float up the the top and as a result there is a pocket of air covering the hole. The bubble won't allow fluid to drop into the hole.

Thanks for all of the help guys, Steve