Brake "spongy" feeling

[Yeobh]

Frankly the percentage of users among the 800+ HDB vehicles workshops is very very small.

Off hand I can list three workshops

 

a) Poh Loon Auto Service ( Caltex S/stn)

71 Fankel Ave , Tel: 62453403

Boss: Mr Richard Choy

 

b) LKW Motor

Blk 17 Sin Ming Ind Est, Sect A #01-55

Tel: 64524906 Boss : Mr C L Fong

 

c) AutoPLus

27 New Industrial Rd Tel : 64872727

Foreman: Mr Sng Hock Chuan

[Kopikao]

I have already done bleeding.. it improves.. but after 1month +.. it starts to be "spongy" again...

[Kopikao]

I had my done at CK motor, AMK autopoint 01-02...

[Discoburg]

If thats the case then it is time for you to change your brake hose.

[EventH]

How much for bleeding the brake oil?

[Gearoil]

The spongy feel in your brake system could be due to many causes but namely it is air that remains trapped or is getting into your purged system.

 

Firstly it is due to the brake hoses but changing to steel braided ones sometimes do not completely eliminate the problem.

 

Then you will need to look closely if air is indeed getting in thru' the seals.

 

There are a few seals found in a hyraulic brake system ( of course some seals are found in the Artic ice region but these seals do not usually give you a spongy feel... )

 

Namely those in the brake pump and those in the brake calipers. Although these seals do not usually fail but it would leak if wear and tear has occurred. Check also the banjo joints that connect your hoses together as they also do leak.

 

In short, any parts that are subjected to movement, or high pressure actuation need to ensure that they are sealed tight.

[Jamesgetz]

is there any good and reliable workshop which u would recommend to do the checks and vacuum bleed??? needless to say, brakes are damn impt and would want someone which i can rely on to solve my spongy brake problem

[Sotong_kia]

I think hor, this is the design of the Optra one leh.. Dunno why.

 

I remember the test drive vehicle is like that. My own car also light that.

 

And it is not that the brakes are ineffective. I did a few high speed braking and they are effective, but the feel is just very different from many cars.

 

For the Optra, the brake power comes when the padel is depress mored. And on few occassions, even at low speed, I did E-brake, and it stopped on time, even the ABS was activated (tyres are still quite new, stock). So that means the brakes were effective. Just that the brake pressure graph is different from many other vehicles.

[Gearoil]

This should be basic mechanical skill for almost all car workshop to do...those at AMK Pt should be well and able to do such things.

 

But to really find the 'sponge' in your brakes is a totally different matter...becos one driver might not feel the 'sponge' while the other driver will not get the 'feeling' or feedback he wants...so really subjective, leh!

 

The latter is usually the 'racer boy' type of driver!

[EventH]

Here is how my brakes "feel" like.

 

When car is off.

When I repeatedly step on the brakes, they get harder and harder, eventually it will be impossible to push the brake paddle down.

The paddle will only slowly go down when the engine is turned on.

(This is said to be normal brake behaviour by my mech)

 

However, I still feel that my brake paddle travel is too long b4 heavy braking take place.

 

During emergency braking(touch wood), the paddle will go almost all the way down, ABS comes in, and I still can still feel the paddle travel a little bit more (half a inch??) before it hits metal.

 

Am I expecting too much or is this a sign of problems with my brakes. thanks.

[Jamesgetz]

the part abt turning off your engine and then stepping on the brake pedal a few times and the pedal 'locks' or become stiff is normal.

 

i also have this problem with spongy brakes. drove my friend's car which is the same model and his does not have the spongy feeling... quite tempted to do the vacuum bleed but it's quite exp. called up one of the workshops recommended by yeobh. it costs almost $70+ even if you bring your own brake fluid. thinking v hard whether to give it a try...

 

at stamford tires, the brake fluid flush (no vacuum bleed) is only $30 with mintex brake fluid

[EventH]

what is flushing?

 

drain everything and replace with new fluid?

[King]

If your mechanics is still using the "1950s leg-power" way of bleeding your hydraulic brake sytem, the chances of getting rid of all the air bubbles in the system is very slim for this generation of cars.

The best way is to use pressure bleeding and the next alternative is to use vacuum bleeding.

 

Ps attached is a vaccum bleeder with a automatic brake fluid refiller.

but yeo, not a lot of workshops use this equipment

[Yeobh]

To most of the mechanics in the states, vacuum brake bleeder is a stardard personal tool nothing speciall about item . Over here our shop operators just don't know how to put in small investments to increase thier mechanics productivity and improve thier image.Maybe they reckon it is cheaper to use thier born-with senses and muscles.

 

PS I always believe there is always a simple and cheaper solution to a complex problem.If you spend time to search for it, you will get it.

[Yeobh]

To do a complete flushing, follow these simple steps

 

a) vacuum out as much as possible the used fluid from the brake reserviour.

b) pour in new fluid

c) Release brake bleeding screw one at a time - starting from rear left.

d) vacuum out the fluid from the bleed screw as much as possible.

e) Replenish the fluid in the reserviour

f) Keep on vacumming until you see new fluid flowing out without bubbles.Stop and tighten bleede screw.

g) Repeat process d,e & f,

h) Go for brake test.

[Tann]

Alo you all forget the magic => is like that 1

 

Hi Spongy feeling brake can be rectify once and for all without much cost and is very effective.

 

Cos I ve done my OPTRA 1.6A and the SA asked how come my brake is so good and what did i do to improve it.

 

My answer to them was, MY MAGIC => i cannot tell or say it. (hahaha)

 

Call me : 91052248

[Yeobh]

All trained mechanics use avaliable information & simple logic to narrow down the problem to the source. No magic skill is required.

[Kohks]

i think just use leg power is sufficient.

 

just make sure brake fluid reservoir is always full or at least above minimum level. so a rough procedure would be :

 

1. brake fluid reservoir always above minimum level.

2. at the brake piston, attach a tube (those for fishtank use is ok, just buy the correct size) at the outlet nipple to receive the brake fluid. must attach a tube to ensure brake fluid is continuously pump out and no air is able to get in. during this time if there is air, should be able to see it coming out. btw use a sufficiently big container to receive the brake fluid.

3. pump the brake until you see fresh brake fluid oozing out from the outlet nipple. always make sure Step 1 is ok.

4. repeat with the other brake piston.

 

btw not advisable to totally drain out brake fluid before doing the above procedure as you might need more brake fluid to totally bleed out all air.

 

if still spongy after a month, better check brake fluid resevior is ok ie no water can get in, brake hose ok, hydraulic connections not leaking.

 

the best thing is you can do this by yourself cheaply as often as you like. just don't dirty the floor with brake fluid.