Brakes poor -- servo, disks?

[Colm]

Hi All,

The brakes on my 1.4sx are very poor, but particularly when the car is cold. It has done 48k, never had disks, but had pads only 10k ago.

When it's cold it sounds like the pads are grinding off the disks (checked pads, not overly worn) and even at slow speed and hard braking the car seems to just coast on way past where it should manage to stop.
When the car is warm it's not as bad, and the grinding is gone, but it's still WAY below par.

There isn't any shuddering from the wheel to indicate warped disks, however, could this still be a disk problem? or possibly a servo problem?

As it's off to the garage next week any comments would be appreciated, I'm afraid they'll just blindly change the disks and pads and ignore anything else that could be causing it.

Thanks in advance,
Colm.

 

[Nigel]

Poor Brakes

There are a number of factors that cause poor brakes. One of the most common that people tend to overlook is the brake fluid itself. If it gets contaminated by condensation, air or other substance then it seriously deteriorates the performance.

Next up are the seals. These are strategically placed to be the most awkward things to check and replace by ALL manufacturers, not just Fiat!

Then there are the brake pipes themselves. Any corrosion can cause seepage and loss of performance.

The servo may have a leak, pressure or fluid escape can cause brake loss.

One big culprit are the brake calipers and cylinders. If these have never been serviced they tend to get all sorts of corrosion and crap in them and they can be a bugger for poor braking. These can be freed up at home, simply by going through the brake pad replacement routine (you don't actualy have to replace the pads) and then pushing the piston back in and then gently pressing the brake pedal ONCE to extend the piston back out. Repeat that a few times on both sides and then put it al back together and test.

There may als be a brake balance valve on your car (I don't know on you model) which may need adjusting. Do you have drums on the rear? If too much pressure is going to the rear of the car you will get a poorer performance.

Pads and disc are the last things that really cause poor brake performance. Providing there is "pad" on the pad and the discs are within tolerance then they will work, it is the "push" behind them that is the cause.

There is always a possiblility that you have the carpet or floor mat rucked up behind the pedal.... don't laugh, I mended a young ladies Renault 5 clutch by adjusting the carpet!

Cheers

 

[Ian]

Rears

I had a similar lack of braking and traced it to a sticking cylinder on one of the back brakes. I know you get most of the effort from the fronts but I was supprised at the difference when the back drums were adjusted right. I still haven't managed to get the "automatic" adjustment working well yet though!

 

[Colm]

new brakes fitted

Nigel/Ian,
Thanks for your response. I had it to the main dealer yesterday. They fitted the following:

disks - 66
pads - 47
shoes - 85
drums - 142

labour - 140

vat - 60

(all prices in euro)


I'll give them 100 miles or so to bed in properly before i really try them out, but thankfully the grinding is gone, the car now stops when i brake! and i can't drive with the handbrake up anymore!


Colm.