General braking problem

Currently reading:
General braking problem

bazNICHOLS

New member
Joined
Jul 26, 2006
Messages
4
Points
2
hi there

ive got a problem or two with my 94 uno 999 fire.

since it hit a large pothole a couple of weeks ago, theres been a bit of brake squeal and the brakes have been sticking on and off. the car will get to 30, struggle at that speed then shazam! the brakes release and i head towards the windscreen.

the squealing and sticking have been the same until today, the sqealing has got more consistent, with a hint of rattling. braking now sounds as if theres a traffic cone being dragged under the car, and they're undoubtely less effective (about 50%)

any ideas? btw, i have a notorious uno handbrake which i've tightened a while back (before pothole day) but is still loose

cheers
 
mad.....possibly
poor student....yes
mechanically minded....not really

i'm gonna take a look tomorrow and see what i see, any further suggestions appreciated
 
bazNICHOLS said:
mad.....possibly
poor student....yes
mechanically minded....not really

i'm gonna take a look tomorrow and see what i see, any further suggestions appreciated


Its possible you may have bent any number of things if you hit the pot hole real bad and buckled the wheel . You need to know which break is sticking And follow a process of elimination good luck
 
Last edited:
One possible answer is that the brake dust shield (the metal backing plate) has rusted through and the pothole has broken it off its mountings. This happend to my Uno a short while ago, and it left the the dust shield rattling around. I got all sorts of knocks and grinding noises, though it didn't affect the braking.

To solve it, I took the wheel off and pulled the remains of the backing plate off on both sides. End of problem!

What might be happening with your Uno is that the backing plate has intermintently got caught between the disk and the brake pad causing your problems.

As this is a safety issue I'd get it looked at IMMEDIATELY. Driving with dodgy brakes is a definite no no. Fingers crossed it will be something simple and you'll be motoring on your way again.

Let the forum know how you get on, and any other queries feel free to ask (y)

Chas
 
While Chas' explanation is a very good one, I also wonder if the hitting-a-pothole was a mere coincidence given that you have also had handbrake issues - I personally suspect that the rear shoes are completely worn out, 'grabbing' (self-locking-on), and giving metal-to-metal contact.

Because the shoe lining wears in a wedge shape, what sometimes happens is that the lining detaches from the shoe and jams itself between the other shoe and the drum - dramatic when it happened to me in an old 128, basically the brake locks on and doesn't come off again! Although this isn't quite what you have, I still wonder if yours could be some variation on this theme.

I agree with the others - DON'T drive the car until you have the brakes sorted - it's just not worth the risks (unpredictable failure giving damage to your car, you, and other people around you and their property, to say nothing of the inconvenience and COSTS...)

But having said all that, it's simple to investigate yourself. Check the front brakes and their dust shields, as Chas says. If using the car's own jack to remove the wheels, don't crawl under the car when raised - you should be able to see/do all you need to from beside the car, even changing the pads is not difficult.

Remove each rear wheel and use a 12mm spanner to remove the two bolts (one 'special' with a long pin sticking out) that secure the rear drum. With the handbrake off, the drum should pull off fairly easily (if not, try striking the flat part in the centre of the drum as though you were trying to knock it 'on', the vibration will loosen the rust, aided by a few squirts of WD40 around the centre hub.)

With the drum off, you are looking for the thickness of the brake shoe lining (the material attached to the steel backing) - needs to be at least 2mm thick in my opinion, as this thickness will last at least a year till the next check.

Perhaps consider referring to a Haynes manual - try http://www.unoturbo.za.net/ for a download - as Haynes does a good job of explaining jobs like working on the brakes. You don't need many tools and the parts (from a general clutch/brake shop) are good value considering their importance and lifespan. But you need to do a careful and thorough job, and if in doubt about any part, please seek a second opinion in person (or perhaps post pictures to the forum!)

Thanks,
-Alex

PS Nice description of the sound ("like a traffic cone being dragged under the car", raised a smile as I wonder how you know what this sounds like ;))
 
Last edited:
Sooo. off topic, but on the last stage rally i did i was cutting a corner a bit too much and dragged a cone about 1/2 a mile, so i know what that sounds like as well.


Back on topic, i would also say don't drive till its sorted, check out what Chas and Alex have said it can't be much else.
 
thanks for the advice, i'm off for a look now (its parked outside my girlfriends house at the mo)

i'll let you know how i get on

baz
 
alexGS said:
If using the car's own jack to remove the wheels, don't crawl under the car when raised - you should be able to see/do all you need to from beside the car, even changing the pads is not difficult.

One other helpful pieces of advice when jacking a car, whether it is with the supplied jack, trolley jack and even when using axle stands is to do the following:

With the wheel off, place it under the front suspension arm locating points or chassis rail on the side of the car you're working on. If the jack/ axle stand fails, you'll still have some means of stopping the car from crashing straight to the ground.

Whenever I work on a car with a wheel off, I always leave the car on axle stands, with the trolley jack just supporting some weight AND the removed wheel underneath a load bearing point. This gives three means of stopping the car from collapsing and squashing you in the process (y)
 
gt3man said:
I don't like Axel stands i use some good breeze blocks

Concrete breeze blocks????:eek:

Noooooooooooo! NEVER use bricks or concrete breeze blocks as they can crumble under the weight of a car. Axle stands are fine if used correctly, though as mentioned I always use back up support when working under a car.

You can't be too careful...
 
1986Uno45S said:
Concrete breeze blocks????:eek:

Noooooooooooo! NEVER use bricks or concrete breeze blocks as they can crumble under the weight of a car. Axle stands are fine if used correctly, though as mentioned I always use back up support when working under a car.

You can't be too careful...

did you not see i said "good":p
 
gt3man said:
did you not see i said "good":p

Good or not, I'd never use concrete to support a car! All the warning advice I've read over the years says 'no!'. However, as secondary means to support a car (i.e as a back up measure for axle stands failing) they're ok, but I'd always use substanial axle stands as the primary means. You can't be too careful when working underneath a car ;)
 
Sure Axel stands are what they are made for. Personally i have never used them so i cant comment on there stability. I'm sure there are a few variations of stand on the market, some better than others I would guess. However if I was working on a car using support other than ramps. I would stick to my blocks, as I can get more contact surface area out of these to the car, than any stand. So in theory more support and less chance of a failure

note..... (my car is lightweight and the position I have used them in, in the past has been flat to the car & low to the ground. It maybe dangerous or, otherwise for people to use this method of support. This is what i do myself for my own application)
 
Last edited:
Very good question thepottleflump!

There are two triangular reinforced areas in the extreme front corners of the floor - each has a round hole in it. These are good for the axle stands BUT that is also where you want the jack, of course...

The FIAT-recommended place for the jack is on the bottom edge of the gearbox bellhousing, in line with the sump. This is a problem for my Uno Turbo as I can't get the jack under there (50mm lowered suspension!) As I recall, it's fine with a standard Uno. But you need quite a bit of lift on your trolley jack to get it high enough so that axle stands can fit in the aforementioned places.

If your trolley jack is narrow, you may be able to place it under the saddle-clamp for the front control arm, and still fit the axle stand next to it.

Another way is to use a piece of wood, ideally with a notch cut in it, to spread the jack's force along the sill flange (a good test for rusty floors/watch carefully while raising!)

Or, you can do the reverse - place the jack under the reinforced-hole triangles, and place the axle stands under the sill flanges...

I reckon the one thing to avoid is placing the jack under any moving parts (e.g. don't jack the control arms...) and also avoid placing the axle stands under the floorpan itself - it buckles in an instant!

-Alex
 
thepottleflump said:
Where is the best place for stands on the front end. On the back end I've tended to jack from the axle and put the stands under the side members.

I always jack up and support a car from a load bearing point on the shell/ suspension. You have to be careful with some front wheel drive cars because jacking in the wrong place can cause the shell to distort :eek:

At the front I support my Uno on stands using the inner arm suspension/ roll bar mounting points, and tend to jack up using the gearbox mounting point on the passenger side and something similar on the drivers side (I forgot what it is, and can't check because my Uno is 7000 miles away :eek: ).

The owners/ Haynes/ Porter manuals will show you the jacking point locations on the Uno (y)
 
Back
Top