Brake problems

[IcutMetl]

I can't seem to get the rear brakes on my R to work at all. They were toast when I bought it, but I put new rotor and pads on, plus cleaned up the rear caliper good. Even then, I couldn't get fluid to pump from the reservoir.

I just took apart the master cylinder today, de-gunked and cleaned it out well, and put a rebuild kit in it. Still have the same problem. Filled the brake reservoir, no matter how many times I've pumped the pedal, I can't get anything to happen but a few bubbles coming up.

I've bled a lot of braked in the past with no issue, but this is the longest it's ever taken to get fluid to flow. I've got a rear caliper rebuild kit, but I don't think that's the issue- I disconnected the rear of the line and still couldn't get fluid to flow. Any ideas?

Thanks!

[hartwill]

Go to the autoparts store and buy a hand bleeder. It is a good investment. Ive had a few brakes that did that and worked fine after I used the hand bleeder.

[DnB_racing]

disconnect the line from the rear caliper and see if you can get fluid out of the line, this will tell you if its a caliper or a master problem... did you make sure the bleeder itself was not plugged?

edit: sorry I just saw you did this... it must be the master or the line itself, take the line of the master and see if you can blow through it

[IcutMetl]

I disconnected the line from the rear caliper and pumped the brake pedal; I could hear sound coming from the banjo fitting, but no fluid came out.

I bought a Mighty Vac pump from the auto parts store and followed the directions, but couldn't get it to pump fluid either...and I tried multiple times.

Since my front brakes are real spongy, I decided to use the vac pump to bleed the front calipers and see if that would make it any better. I pumped plenty of fluid thru each caliper, but the lever is still super soft and will go right to the bar without too much grip force.

It's allllllmost getting to the point where it's irritating me!

[bigmatt61]

Do you have the stock lines on the front? If so the rubber is expanding and allowing the lever to go all the way to the bars.
Steel braided lines and a can of BRAND NEW dot4 or 5 fluid will fix the spongy fronts. Use that mighty vac to get that old fluid out!
As far as the rear, could you have something clogging the line?

Matt

[Rich250RRacer]

Originally posted by IcutMetl
I disconnected the line from the rear caliper and pumped the brake pedal; I could hear sound coming from the banjo fitting, but no fluid came out.

I bought a Mighty Vac pump from the auto parts store and followed the directions, but couldn't get it to pump fluid either...and I tried multiple times.

Since my front brakes are real spongy, I decided to use the vac pump to bleed the front calipers and see if that would make it any better. I pumped plenty of fluid thru each caliper, but the lever is still super soft and will go right to the bar without too much grip force.

It's allllllmost getting to the point where it's irritating me!

On the front, try taking out the top caliper bolt and loosening the bottom bolt. Tilt the caliper out so the bleeder is straight up and try bleeding it again. This worked great on my 450 that had a spongey brake. I couldn't believe the amount of air that was hiding in there, and this was after I had spent two hours bleeding it with the calipers bolted in place.

[hartwill]

make sure you pump it to build up pressure before you loosen the bleeder, and do them one side at a time. or you can gravity bleed them.

[danhung11]

On my most recent brake bleed, I was having similar problems with the fronts. troybilt thought there was a problem with the bleeder valves, so he wrapped the threads in some plumbers tape, and threaded them back in. It solved the problem, apparently the valves were letting air in and couldn't let the vacuum bleader fully "seal".

There are a lot of remedies here, so try one at a time and see what the deal is.

Good luck!
Dan