hi all hope u guys and girls can help ive just fitted 4 potts and twin to the back but we have put 5 ltrs of brake fluid thru now and still got a flat to the floor pedal sometimes hard then leave for a min then flat to floor ive fitted a new master cylinder today we done it all again and still the same what are we doing wrong or what is the problem please help it driving me nuts cheer richie

 

Are you sure it has been completely bled correctly ?

Sounds like there is still air in the system somewhere?

ps. i thinnk this will be moved to general technical, but you wont find it as the search function has now been disabled lol

 

Have you checked the seals on the calipers? I intend to overhaul the 4 pots when I get some for my car and repaint them.

Just check all of the seals, hoses and bleed nipples. It maybe you could still have air in the system too.

 

Have you got the bleed nipples at the top of the caliper ?
if you have put them on upside down you will never get the air out
Gary

 

5 litres! Thought it was much less in the break system, but stand to be corrected.

 

yes there less in the system but ive still got a flat to the floor problem

ive got the claipers the right way up the the hoses are attached straight down do the have to be attthed so they loop from the bottom if you know what i mean

 

Try attaching a syringe with a tube onto the caliper nipple,fill the syringe with brake fluid and back bleed the system by forcing the fluid through the caliper and up to the master cylinder/resevouir...

 

I know you said you have them the right way up, but is the bleed nipple at the top????? thats what most people get wrong!!!!

 

As said already all bleed nipples at the top and bleed from the furthest caliper from the master cylinder. What are you using to bleed the system?

 

pumping the pedal up and down then releaseing the nipple on the last pump and closing clear fluid come thru

 

Try this technique,

Start furthest away from m/cylinder, i.e rears first. open bleed nipple push pedal down then close nipple let pedal up repeat until all air out on all calipers.

If that dont work you could have flipped the seal in the master cylinders.

 

Any Autofactor will sell bleeding kits. Note that the 'Eazibleed' is difficult to use on the Subaru master cylinder. The kit should cost no more then a fiver, it'll come with a tube and a bottle. It'll help make the bleeding process loads easier. And as said rear passenger side first, rear drivers, and so on. Keep an eye on the reservoir, make sure it doesn't get low or you will just suck in more air.

After the air is gone if the pedel still goes all the way to the floor you either have got a huge leak somewhere or the M.Cylinder seals have deteriorated.

 

Are these brakes the WRX 4 pots, STi brembos or some other make?
Nick

 

start furthest away from master cylinder pump pedal hard about 6 times quite fast on the last pump hold pedal down relise nipple aload of air should come out keep doing on same nipple untill just fluid comes out then start on next and so on

ive never had a problem yet

 

You forgot about overcoming the load sensing at the rear. I usually use a small trolley jack on each rear tie bar just take the weight a little, but not enough to lift it off the axle stands.

 

I did my my00 only last week, and i didn't have any ill effect from any load thingy on the rears.....
And the suspension was at full droop!!

 

*cough* AS Performance - Rally Motorsport Specialists *cough*

 

I use the EZ-bleed systems on my car and it works very well. I have an AP racing brake system and its a PITA to clear out.

 

It is m ore difficult on your own but the kits do work well, just a oneway valve on a rubber tube. I did one recently which was fine.

try not to press the pedal all the way to the floor as it can damage the MS seals.

Dave

 

Just a quick addition to this statement: The eazibleed kit I purchased did not fit the master cylinder on a 93 WRX, I had to fashion my own adapter. Once working it did the job very well but it was a pain getting it there, I should have bought the cheapo kit which I have since done; loads easier and the end result was exactly the same.

 

Any joy yet???

 

dont no if this helps but the correct order is front right ,rear left ,front left, rear right. done with a bleed kit when changed hoses and no problems. and the lines can hold more air than you think

 

This is definately the wrong way to bleed brakes.

The quote below your post is correct.

I take it that 5 litres has gone through the system and not onto the floor via a leak?