Poor braking after upgrading to UK-spec brakes.

Hi guys,

I recently upgraded my jap-spec brakes to uk-spec brakes.

I replaced the following:

* Calipers

* Disks

* Pads

* brake fluid

* brake lines

After the upgrade i have bleed the system a couple of times.

For some reason i need to floors the brake-pedal before anything happends.

It's really bad.

Did i miss something for this upgrade?

Are the calipers on the correct sides? All the bleed nipples should be at the top, if not they wont bleed properly and still be full of air. Id say have a look at that first.

Yeah the calipers are installed correctly with the bleed nipples on the top.

How much fluid have you bled through ?

Is the master cylinder okay ?

Sounds like there is still air in there to me.

Is the warning triangle on?

H.

I guess i've bled somewhere around ½ liter. I have bled 4 times. I have of couse filled up meanwhile.

I don't know if the master cylinder is ok. I assume that it is working as intended. The car did not have any problems braking prior to the upgrade.

I don't know if my assumption is correct?

No warning triangle.

Sounds like there is still air in there to me.

 

Is the warning triangle on?

 

H.

agreed. happened to me when i upgraded, hand to spend ages bleeding it and lots of brake fluid was used to get it right

Did you bleed the ABS unit??

agreed. happened to me when i upgraded, hand to spend ages bleeding it and lots of brake fluid was used to get it right

You shouldnt have to spend ages, we did my car after fitting new hoses and calipers and it took under 1 hr and

approx 1 litre of brake fluid, we bled through all the old fluid and replaced with new.

We did use a vaccum bleeder though and the brakes were 100% spot on first time and still are a couple of years

later

Tricky-Ricky: I only bleeded the 4 calipers - should i bleed the ABS-unit seperately?

DnK: I used a vacuum bleeder as well. I think i bled it 4 times so far

Have a look in the WSM in the brakes system section BR66 covers the abs unit

I didn't have to bleed my abs and just bled the whole system via each caliper

and the brakes were spot on.

Worth doing the checks though incase thats the problem but i'd be inclined

to bleed it once more.

http://www.turbosupras.com/pages/en/pages/technical/a80tsrm.htm

I will try that out tomorrow

thanks.

No problem

Good luck

Tricky-Ricky: I only bleeded the 4 calipers - should i bleed the ABS-unit seperately?

 

DnK: I used a vacuum bleeder as well. I think i bled it 4 times so far

When i changed my brake lines, i had a very spongy peddle until i bled the ABS unit.

When i changed my brake lines, i had a very spongy peddle until i bled the ABS unit.

same here and it was a pain to bleed to!!

Push all the caliper pistons fully back home into all the calipers with the bleed nipples open, then bleed the syatem again. How are you bleeding it? I have seen some very "odd" methods used that plain just do not work.

To make sure you are getting new fluids into the calipers add 3 drops of food dye to your new fluid ( I used red) then when the fluid comes out the calipers pinky then your sure you have new fluid in all the pipes and calipers, in all the supra's ive had i have never bled the ABS unit and have always had megga brakes using UK calipers - stock disc's - porterfield R4 race pads.

And i always use an easy bleed kit, push's the fluid into the system using your car tyre valve to pressure the system up.

Chris: I will try to push back the pistons.

The way i bleed: I start with the brake furthest away from the master brake cylinder and then work my way to the closest brake (Left rear -> Right rear -> Left front - Right front).

I have tried the other way around as well - starting with the closest wheel.

Little num: i will try with the food dye

If you still have the stock type rubber brake hoses clamp them off one at a time, or both fronts and both rears, if you have two hose clamps, and you can narrow down where the air might be in the system. Be careful using anything other than proper brake hose clamps as you can easily damage the hose and leave it liable to a burst if you are brutal with things like Mole grips.