Help needed! Need 2 pumps before brakes work

[OleVix]

The brake system doesnt have any leaks and has been aired properly. But I still need 2 full pumps on the pedal before theres are braking, and then they work great.... Ive just had the rear calipers off for a refurb, do I need to screw the piston further out??

[ch427]

Sounds like you still have air in the system, did you use an eezi bleed tool or just the pedal?

[TJC46]

OleVix said:

The brake system doesnt have any leaks and has been aired properly. But I still need 2 full pumps on the pedal before theres are braking, and then they work great.... Ive just had the rear calipers off for a refurb, do I need to screw the piston further out??

First question....did you have this problem before you had the calipers refurbed?

If not then obviously somethings gone wrong when you refitted the calipers or you have air in the system.

Someone else will be along with more knowledge than me, but you screw the piston back to remove/change pads but im sure the piston finds its own position first time you press the brake pedal.

[blitzracing]

The piston will now be in its correct position as even with two pumps you have brake pressure. This is definitely air in the system. If you use a brake bleed tube with a valve in it, air can get drawn back up the thread of the bleed nipple when you release the brake pedal- so it will never bleed. You are better off getting someone with a spanner to open and close the bleed valve as you depress and release the pedal.

[pb450]

You said they're aired but that still sounds like there's air in the system somewhere. Sometimes it can be a devil of a job to truly purge all air. I'd advise another bleed or two.

[OleVix]

ch427 said:

Sounds like you still have air in the system, did you use an eezi bleed tool or just the pedal?

I used just the pedal, but the system was completely empty because of the full body off refurb, new front 887 calipers and refurbed rears...

It wasnt like this before no

[OleVix]

blitzracing said:

The piston will now be in its correct position as even with two pumps you have brake pressure. This is definitely air in the system. If you use a brake bleed tube with a valve in it, air can get drawn back up the thread of the bleed nipple when you release the brake pedal- so it will never bleed. You are better off getting someone with a spanner to open and close the bleed valve as you depress and release the pedal.

we did this two people, one pumps and holds the pedal, second guy opens and closes

[ch427]

Get yourself a gunson eezi bleed, a very handy tool for £20. Just remember to drop the tyre pressure before using it.

[AceOfHearts]

Mine was like this after I replaced the front brakes. Make sure you remove the black cover from the engine bay and bleed the master cylinder

[AceOfHearts]

Heres my old thread

http://www.pistonheads.com/gassing/topic.asp?t=793...

[phazed]

Ole.

Don't forget the bleed nipple on the master cylinder!

[OleVix]

Yep that nipple on the master broke clean off. Putting 0.5 bar of pressure on the fluid reservior while a friend is pumping the pedal and right rear wheel nipple is open helped a bit, now I only need one push on the pedal and the brakes work at the bottom... will air out more tomorrow....really dont want to remove the master cyl, looks a pig job

[OleVix]

Managed to get 99% of the air out with a vacuum device connected to the caliper nipples! Thank god/allah/jeebus or whoever is up there