Bleeding brakes

[Jim-p]

Hi all, just changed out my two rear calipers (had another post here about the parts) and while they're working fine. I'm not happy with the firmness of my brake pedal, I feel I have to press it too far before  getting  a response. So I assume I didn't do enough bleeding. Is it just a case of going and bleeding both again and putting a decent bit of fluid through or will the air have travelled up and there is a better approach? Fluid flushed last May so I shouldn't need a full flush.

[Stivino]

What did you use to bleed the brakes and did you do it until you could see that there were no more air bubbles? 

[Jim-p]

1 hour ago, Stivino said:

What did you use to bleed the brakes and did you do it until you could see that there were no more air bubbles? 

A diy kit, a clear tube that fits on over the nipple and into a bottle that already has enough brake fluid into to cover the other end of the tube. We went a few rounds of pressing the pedal till the person with me couldn't see any more bubbles coming out. They, being significantly more mechanical than I said we were done. The pedal did feel firmer I thought before doing them, although with sticky calipers. What little reading I've done online suggests bleeding is a starting point.

[Stivino]

If you've got all the air out, they're bled.  You could do them again, just to convince yourself.

Did you fit new pads too or, just the calipers?

This is my set up for bleeding brakes, I don't have any help, it's a one man job.

[TonyHSD]

But when you bleed the rear because of callipers replacement, have you bleed the fronts too? 
Did you bleed with engine on or off? 

[Stivino]

7 minutes ago, TonyHSD said:

But when you bleed the rear because of callipers replacement, have you bleed the fronts too? 
Did you bleed with engine on or off? 

Totally irrelevant. 

[Jim-p]

12 hours ago, Stivino said:

If you've got all the air out, they're bled.  You could do them again, just to convince yourself.

Did you fit new pads too or, just the calipers?

This is my set up for bleeding brakes, I don't have any help, it's a one man job.

Yep, same set up as that. I replaced the pads as well, discs for that matter too. Do you use a stick or something to hold down the brake pedal while you tighten before letting it back up? I thought I was going to have to do it myself as well until my help showed up. My fear now is that if I had air, it would have travelled up the system. I will bleed it again but I may need to put a decent amount of fluid through it now.

Edit: love the blue caliper btw

[Stivino]

I don’t use anything to hold the pedal down.  The tube is tight enough on the nipple that air can’t get in and the end of the tube is in the fluid, so air can’t get in there either.

If you’ve changed the discs, pads and bled the brakes, I’d expect it to feel different.

[oldcodger]

Don't forget it will take a good few miles to bed in the new discs and pads  when the feel should steadily improve, though the rears will always take a bit longer than the fronts as they do not get the same force.

Always found using a £20 kit like the Gunson EasiBleed make bleeding the brakes and clutch an easy one man operation.

 

[TonyHSD]

16 hours ago, Jim-p said:

Yep, same set up as that. I replaced the pads as well, discs for that matter too. Do you use a stick or something to hold down the brake pedal while you tighten before letting it back up? I thought I was going to have to do it myself as well until my help showed up. My fear now is that if I had air, it would have travelled up the system. I will bleed it again but I may need to put a decent amount of fluid through it now.

Edit: love the blue caliper btw

Most likely air was locked into the abs module. You definitely need to bleed all 4 corners. You may want to check service manual for proper procedure and follow up the instructions. Some cars require engine ON, some need to be set into brake valet mode etc or run the abs pump to get air out.
Parking brake on or off it’s also important to check how should be set before you start bleeding. old school pump and hold the pedal works best.
After you finish and if you still have soft pedal you can do few harder brakes on slippery roads to activate the abs , this sometimes helps the air escape into the reservoir. Pad bed in is important no doubt but this won’t change pedal feel., just stopping power.
Pedal should be hard with quick response otherwise there is an air inside. 

[Stivino]

There is no reason for air to be in the ABS module and no way for it to get there by removing a rear caliper unless the system was drained, which didn't happen. 

No need to run the engine either, that only makes it easier to press the pedal.

[TonyHSD]

Any news on the brake job ? 
One bubble of air in the rear callipers will travel up the system straight into the abs module and it will cause exactly what the op has experienced. Proper full system flush is the only way to get it done correctly and have a nice and sharp brake pedal response. 👍

[Stivino]

11 minutes ago, TonyHSD said:

Any news on the brake job ? 
One bubble of air in the rear callipers will travel up the system straight into the abs module and it will cause exactly what the op has experienced. Proper full system flush is the only way to get it done correctly and have a nice and sharp brake pedal response. 👍

Utter tosh, again.