Spongy brakes?!

[WallaceGlanza]

My brakes are crap. :homer:

I drove the girlfriend's bubble shaped clio the other night and was performing emergency stops every time I tried to slow down, then back in my car today I almost didn't stop at the first junction I came to.

I fitted new 3G discs, mintex pads, braided lines and bleed them with dot 5.1 fluid a few months ago, they felt better then but still not brilliant. I didn't change the rear discs or pads and I know the pads are low but the rears don't do much anyway.

The brake pedal has no feel at the top and takes a lot of pressure to start any considerable braking force. When the pedal is pumped with the engine off the pedal stiffens up and is much stronger - how I would like it to be all the time, is this because there is still air in the system after being bled?

Is this just normal with all starlets and older cars, I would really like the brake feel that my gf's clio has.

 

[GTti]

Air or contaminated with moisture, have a go at bleeding them again.

 

[starbogt]

I'd try bleeding the brakes again and also check the master cylinder for leaks and movement. Thay make a master cylinder stopper so there must be some fault that can occur during heavy braking!. I'm sure someone who's experinced the same problems will come along soon. What mintex pads are you using also?

 

[simon-GT]

i had a go in 1 of the new astras the other day, the braking was so dam good, only required u to touch the brakes n would stop. afterwards, go back into my gt n felt like my brakes were not working, lol.

 

[WallaceGlanza]

I've already re-bleed them once and they improved then lost feeling again, the fluid level hasn't gone down so there's no leaks but could there still be air getting in?

I'm using mintex 1144 pads, they were bedded in properly too.

Would the abs not working have anything to do with it?

 

[WallaceGlanza]

i had a go in 1 of the new astras the other day, the braking was so dam good, only required u to touch the brakes n would stop. afterwards, go back into my gt n felt like my brakes were not working, lol.

Yeah thats what I was like today but I still think my brakes should be better than they are.

 

[Rory]

Start re-bleeding the brakes, from the furthest away nipple to the closest (from the master cylinder) Front and back.

Took a couple of times to fully have the air out of my brakes when i put them on.

 

[goldenvtr]

just after fitting my 2pots the pddle had no feeling, it took a few times bleeding to get it right.

remember some pads have a break-in layer too before they work fully.

 

[Adam_Glanza]

to be fair i think 3g discs and mintex pads are just shite imo.

ok starlet brakes have never been amazing but there not really great.

just shows how far new cars have come in braking!

 

[WallaceGlanza]

Guess a good bleed is in order again then. Should I have a nice constant firm pedal, like it is after its been pumped a few times with the engine off?

Just to check I'm bleeding it correct too, this is what I do:

-Get an able assistant to pump the brake pedal 10 times then hold the pedal down.

-Unscrew the nipple furthest from master cylinder (rear passenger side) and let the fluid drain out.

-Close bleed nipple then pump again as necessary until no air bubbles are seen in the fluid.

-Bleed remaining brakes starting furthest away from master cylinder and working towards it.

Correct?

 

[WallaceGlanza]

Just want to check that the above sequence is correct and you do it with the engine off, as I'm about to bleed them again?

Also does the abs effect the brakes at all except for the obvious of stopping them locking?

One last thing, when the pedal is pumped with the engine of and the then held, when the engine is started the pedal goes down instantly and loses its feel, is that normal?

 

[Dan3SGTE]

yes bleed the brakes with the engine off mate.... you want have to pump out 10 times worth of fluid mate, i only did about 4 pumps, more then enough, hold down last pump tighten nipple......

If everything is ok it could be the master cylinder as that could not be pushing the pressure through the system..... If they are all bled properly that is with no leaks etc i would say master cylinder.....

 

[Dan3SGTE]

oh and by the way, you have to pump the pedal with the nipple open, the fluid should be squirting out especially up front closest to the cylinder, that would ensure your cylinder is doing its job too.....

 

[Dan3SGTE]

One last thing, when the pedal is pumped with the engine of and the then held, when the engine is started the pedal goes down instantly and loses its feel, is that normal?

perfectly normal mate.. servo assisted brakes do that.

 

[WallaceGlanza]

I thought you pumped it with the nipple closed then opened it, as otherwise it will be pulling air back in each time the pedal comes up?

 

[Phil]

Cusco sell a 'Brake Master Cylinder Stopper' think Ryan-v has one for sale in the Parts for sale section.

ive heard they eliminate alot of the spongey feeling.

Phil

 

[Dan3SGTE]

I thought you pumped it with the nipple closed then opened it, as otherwise it will be pulling air back in each time the pedal comes up?

With the engine off pumping the brakes with the nipple closed will get so stiff you wont literally be able to pump...

pumping when nipple is open will be letting out old fluid and pushing air out and on the last pump you push it hard and leave your foot down, close nipple, pump brakes a few times and you should regain all pressure back in your pedal....

 

[GTti]

What you want to use is a tube on the end of the nipple, pump a few times and look at the fluid thats in the clear tube. It needs to be clear and free of bubbles, when it is then you tighten the nipple with the foot still depressed on the brake pedal.

It's a two man job, you can get a little brake bleeding kit from motoserv which has the tube I speak of.

 

[Rory]

oh and by the way, you have to pump the pedal with the nipple open, the fluid should be squirting out especially up front closest to the cylinder, that would ensure your cylinder is doing its job too.....

This also draws air into the system....

Do as your doing, but close the nipple mid-flow, dont let the pedal reach the floor.
As GTti said, a clear tube off the nipple lets you see if there is still air in the sytem, ie bubbles.

 

[Dan3SGTE]

Rory,
so your saying pump the brakes with the nipple tightened?

this is how i bled my system, remember my problems i had? and now my brakes work absolutley mint....