Can the rear brakes be bled on their own with satisfactory results or is it best to do the whole system?

When I changed all my brake callipers couple of years back the rear flexi pipes obviously weren't coming undone so i kicked the can down the road and left them as still being functional.
The metal extension on one rear caliper pipe let go last Monday so I've been dodging the rain for the past couple of weeks of spare time getting things changed. Which included making new sheet metal brackets ANR 5918, ANR 5919 and the "flat with a slight bend one at the bottom" which, apparently has no part number. Searching the usual supplier suspects indicated that availability of ANR 5918 & 5019 appeared to be spotty with daydream prices on some suppliers.

So I drew them out and made a set of four. Drawings can be sent as a pdf if anyone wants them. Not intrinsically hard to make but something of a PIA to mark out and cut to size making for a slow job. I officially have too many toys, including a 41/64 th drill for the hose hole, so getting it done merely took longer. Cutting the blanks would have been an ideal job for the baby CNC mill I've never worked up enough enthusiasm to get going.

Further searches after the event suggests you can get ANR 5918 & 5019 for £5 - £10 each if you choose suppliers wisely but no one seems to have both.

Clive

The Vogue that me and a mate are resurrecting had had one of the rear callipers changed before we got it and a new replacement (along with a disc and pads) for the other side was in the boot. I picked it up and drove it over to my mates place and the brakes were pretty iffy. Lots of pedal travel, not much stopping power and the ABS and Traction Failure warning came up on the dash the first time the brakes were used. I fitted the other disc and calliper and bled both rears. Brakes were no better. So we bled the whole system from start to finish and the brakes are now as they should be. So I think I can safely say the answer to your question, is no they can't be.

I bled just the rears on mine when i replaced both calipers/discs/pads.

I removed the bleed nipple from the new callipers and fitted them to the car, I swapped the line from the old calipers to the new and the fluid started to pour out, once the bubbles cleared i screwed the nipple in and job's a good un..

Make sure the reservoir has enough fluid in it.

Front goes up tomorrow then and they all get done. 3 litres of DoT 4 in stock so I may as well change the fluid whilst I'm at it.

But I shall pre-bleed the rears the StrangeRover way first. Don't like working on partially filled hydraulic systems.

Clive

Might be a good idea. When we did the Vogue there was lots of air in the rear circuit at the bleed nipple at the modulator. That may have been because it was left dribbling out when the other rear calliper and hose was changed so when it was bled at the calliper it only got rid of the air at the rear end. If you don't allow it to drain out, it may be OK.

https://www.johncraddockltd.co.uk/anr5918-bracket-brake.html

https://www.johncraddockltd.co.uk/anr5919-bracket-brake.html

dave3D
Yep, found the Craddock listing after I'd made mine. But I've not had much joy in trying to get stuff out of them in the past so not on my preferred suppliers list.

Two hours and a litre of DoT4 this morning got the whole system bled with excellent results. Usual hour to do the job, hour to scare up all the bits and bobs of "tools", find the cheat sheet and revise the method. Looking at my checklist sheet last time (first time actually) I did this was on 12 th October 2018. No wonder I couldn't remember how to do the job.

Brakes are better than before, and they were pretty darn good but I had done an accumulator change without bleeding afterwards. Clearly not necessary but I suspect you do loose a bit of ultimate braking oomph.

Couldn't get any flow through the pipes when I uncapped them so the StrangeRover method wasn't gonna fly.

Clive

I also fitted a new accumulator during the lockdown when my car was sorn'ed for 5 months. No real problems with it but it was 20 years old and it seemed like a good idea to change it.
Just unscrewed the old one after depressurising and screwed in the new one. The old one was bloody tight. I had to use an oil filter chain wrench to unscrew it. I feared there was pressure still behind it. It has a fine thread.
However, brakes were soft after I did it and I ended up bleeding the whole system. It needed a fluid change anyway. New bleed nipples on the back as well. I like a few new shiny bits underneath. Impresses MOT guys as well.

A few years ago A BMW mechanic demo'd brake fade for a few of us with a 4 year old 5 series, then changed the fluid and did it all again. Ever since then I try and change the fluid pretty regularly every 3 or 4 years, and I find the regular attention helps keep bleed nipples and such moving freely.