Pinching brake lines?

[Luk3]

I'm about to replace a dragging rear caliper this morning. One of the steps suggests that I pinch off the brake line to stop the fluid from draining. The line is pretty hard and apears to be braided on the inside? I'm worried about damaging it if I pinch it with vice grips. Is it safe to pinch these lines?

 

[JoshMcMadMac]

I have never bothered to do that. Just bleed the caliper off, have some cardboard down, and a container to catch the brake fluid with. You should be bleeding/flushing the brake fluid at that time anyway.

 

[Luk3]

This may be a dumb question but wouldn't the entire reservoir drain once I disconnected it from the caliper? I've never done this before.

 

[oddball]

It can, but unlikely. There shouldn't be more than a few moments between disconnecting the old caliper and connecting the new one. Have the parts handy so those two steps are right next to each other.

 

[Luk3]

OK thanks

 

[Luk3]

It didn't poor out like i thought it would.

 

[2002_lincolnLS]

Well think of it this way, there is no pressure and it is an other wise seal system so there is a vacuum holding the fluid in, only some will leak out as it is not 100% fully sealed so there may be some air in there I mean like a tiny percentage of air in there to allow some to over come the vacuum with the force of the gravity pulling down on it.

 

[joegr]

Well think of it this way, there is no pressure and it is an other wise seal system so there is a vacuum holding the fluid in, only some will leak out as it is not 100% fully sealed so there may be some air in there I mean like a tiny percentage of air in there to allow some to over come the vacuum with the force of the gravity pulling down on it.

There's also the resistance of some valves that it has to go through. The rubber in the cap is actually designed to expand out into the reservoir a little bit to prevent vacuum as the fluid is pumped into the calipers. In practice, the cap seal leaks so much that it doesn't seem to matter.

I've tried to gravity bleed with the cap off the reservoir. There may have been some fluid movement, but it was so slow that it seemed like it would take days to do it that way.

 

[Kumba]

I've tried to gravity bleed with the cap off the reservoir. There may have been some fluid movement, but it was so slow that it seemed like it would take days to do it that way.

I've only ever had luck with that on the front calipers and mostly only on cars without ABS. Newer cars have too much between the master cyl and the calipers for it to work in a timely fahsion.