locked brakes

sixteenacrewood · Post by **sixteenacrewood** » 10 Oct 2011, 09:13

Hi Everyone, I have a 2001 v40
The left front and the right rear brake callipers are locked up.
I tried to bleed the lines but no fluid will come out of these two callipers.

the other two wheels will bleed normally.

Does the left front and right rear callipers share anything mechanically in common?

also.. when I was refilling the master cylinder the rubber boot came out of the cap and now will not go back in, it is as if the rubber swelled to a larger diamiter and is now to large to go back into the cap!

When it rains it pours.

any advise will be a big help

Thanks
Stephen

Post by **Choguy03** » 10 Oct 2011, 09:22

The rubber will go back in, you just have to fidget with it. By locked up, you mean not moving on the caliper pins? If that is the case, remove the 2 caliper bolts and pull the two caliper pins out. They should be nice and lubed and slide freely. If not grease them up and see. Also you may need to replace the two rubber boots. If these are cracked that would be causing your calipers to freeze up.

As for you not being able to bleed the brakes that is strange. Are you getting any air or anything out of the bleeder screw? If you had a leak in your system you would know. You may just have plugged up bleeder screws. You can replace them too, but be ready when you remove them, brake fluid will come out and you will need to give a good bleed.

sixteenacrewood · Post by **sixteenacrewood** » 10 Oct 2011, 09:29

Thanks for the reply!
Locked up..I should have gone into more detail.
the brakes on these two wheels are not releasing. once the brakes are applied the calipers will not release their grip on the rotors. when I open the bleed valve a jet of fluid will shoot out under pressure. I had my wife pump up the brakes and hold down on the peddal, I opened the bleeder valve and nothing comes out, no fluid or air.

I am thinking I have bad flexable brake lines on these two wheels.

Post by **Choguy03** » 10 Oct 2011, 10:17

That is possible. Try taking the bleeder screw out completely and that will determine if you have a clogged bleeder or a clogged line. Although, since you are getting the brakes to clamp down on the line there is a good chance you are going to need to grease up those brake caliper pins. You could have an issue in the line/bleeder but check those pins. One thing at a time and we will get this worked out for you. Any pictures you can take/have would be great too!

sixteenacrewood · Post by **sixteenacrewood** » 10 Oct 2011, 12:54

Ok, the caliper pins were clean and I greased them, I do not think they were binding.

the bleeder on the right rear was rusted and had grit in it, I cleaned it and it is bleeding properly, I will replace it soon but I live 20 miles out in the country.

the left front is now bleeding properly, there was no corrosion on it.

I kept bleeding the left front and the right rear until I used a whole small bottle of brake fluid, so I have new fluid in the system now.

I will test drive it in a bit.

I am now thinking the master cylinder is the problem.

Post by **Choguy03** » 10 Oct 2011, 13:55

That wouldn't cause the the brakes to lock up though. You would have a 'mushy' feel to the pedal. When you brake, the pedal may go down to the floor and not feel hard. Keep us posted.