Front brake disc getting red hot and smoking :O

Mark A

Mark A

Mark A

Soldato
Joined
19 May 2005
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Lancashire
Hi guys,

Yet more trouble with my Focus :mad:.

I recently had the front brake discs and pads replaced with Mintex ones as mine were shot at. They have been great and even seem to have more stopping power than the old ones. But recently Ive been smelling a burning smell that i couldn't quite place where it was coming from. Today i smelt it much worse than usual and then when i pulled up at my house i could see some wisps of smoke coming out from the brake :eek:. The disc was red hot and black in colour but i haven't been hooning around, i just drove to the shop and back. The other disc was just warm as it should be.

Strange thing is i haven't felt it pulling to one side which i would have thought it would do. The car also rolls freely so the brake isn't jammed on.

Any ideas? I'm obviously going to get it looked at but I'd like to get an idea of what it could be before i take it in.
 
Could be either a seizing piston or corroded slider pins.

My CTR had to be recovered a few weeks back with a seized piston, exhibiting the same symptoms as yours. It was utterly jammed solid. I bought some reconditioned calipers (EBC) from eBay, and they've been fine since. Luckily I noticed it before the pad and disc were knackered.
 
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Janesy B said:
Brakes are binding, you'll need to get them readjusted. You'll probably need new pads too now.
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How come they seemed fine for a good few months and then suddenly started binding? Is it normal for this to happen?

Is it a specialist job or something i could have a go at myself? Any idea of cost if i do have to take it in?
 
danza said:
Could be either a seizing piston or corroded slider pins.

My CTR had to be recovered a few weeks back with a seized piston, exhibiting the same symptoms as yours. It was utterly jammed solid. I bought some reconditioned calipers (EBC) from eBay, and they've been fine since. Luckily I noticed it before the pad and disc were knackered.
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The thing is it rolls freely, so i don't think the brakes are jammed on. Its also driving fine and doesn't seem to have lost any power.

If it was binding wouldn't i feel like a scraping sound while rolling along?

EDIT: Just been out to look at the disc again and its still a dark blue/black colour instead of silver. I guess this means the disc is knackered as well as the pads? Thats £40 down the drain and the £50 it cost to get them fitted :(. getting really sick of this car now.
 
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Mark A said:
The thing is it rolls freely, so i don't think the brakes are jammed on. Its also driving fine and doesn't seem to have lost any power.
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The brakes must be binding, there is simply no other possible explanation for them getting so hot. Problem is more likely a seized caliper piston than sliders, the later won't usually cause enough binding to get the pads smoking.
 
Dogbreath said:
The brakes must be binding, there is simply no other possible explanation for them getting so hot. Problem is more likely a seized caliper piston than sliders, the later won't usually cause enough binding to get the pads smoking.
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I aggree.

The first time one of my caliper pistons seized (yes, it happened twice!), there was nothing untoward about driving the car, well according to my wife there wasn't. I did notice a couple of days before that there was a funny smell coming from the front of the car, but ignored it. This was the pad in prlonged contact with the disc.

On the first occasion (when my wife was driving), smoke started pouring from the effected brake/disc/wheel.

On the second occasion, I noticed it due to since having grooved discs fitted, which make a faint whirring sound under braking. When the caliper had begun to seize, I noticed the whirring sound was constant - i.e. without braking. I pulled over and the disc was very, very hot and smoking slightly, and also slightly yellowed.

The car still drove without issue though. I'd suggest you don't drive the car all the time there is a problem with the brakes, unless you can get it to a local and trustworthy garage that is close to home. I was fortunate on both occasions when mine failed, because my neighbour is a mechanic and sorted it for me by fitting the new calipers that I'd bought.

It's usually good practice to replace both calipers if one fails, and the same goes for pads and discs needing replacement on both sides aswell. I've spent about £500 on my cars brakes in the 2 years I've owned it (2 sets of knackered calipers and a set of knackered pads). :(
 
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Dogbreath said:
The brakes must be binding, there is simply no other possible explanation for them getting so hot. Problem is more likely a seized caliper piston than sliders, the later won't usually cause enough binding to get the pads smoking.
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Would this still allow the car to roll freely? The car rolls fine and i don't hear any grinding etc, but then again the engine would probably block the sound out. Also the car doesn't pull to one side or anything, which i would have thought it would with it being just the one disc.

Is there any way to sort this out or will i have to take it into a garage? I'm pretty annoyed about this as i paid over the odds to get them fitted. Think i paid about £57 plus £40 for the discs and pads (Mintex). Now I'm going to have to pay the same again no doubt and this could happen again as i have no idea why its happened. Ive only done 1000 miles or so since i had them done as well.

Thanks for the help :), I think ill get the wheel off tomorrow and see if i can see anything untoward. I'll try and free the piston (if its stuck) with a g-clap and see if that sorts it.

danza, Thanks, that does actually sound spot on. Just started to notice the smell, but it was faint and there was a small amount of smoke. So hopefully there dics aren't ruined. I think I'll take it to a different mechanic this time and see what they say.
 
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Surely if it was binding you'd have a massive amount of brake dust on the wheels? Get it jacked up and spin a wheel to see whether it encounters any resistance.
 
Leeum said:
Surely if it was binding you'd have a massive amount of brake dust on the wheels? Get it jacked up and spin a wheel to see whether it encounters any resistance.
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Yeah, Ive not noticed any extra brake dust. thats a good point actually, I'll have a proper look tomorrow and get the car jacked up.

Is it possible for it to bind intermittently? Because it does sound like the symptoms of a binding pad.
 
If the piston is seizing/seized, there's not much hope for the caliper TBH. Freeing it off temporarily won't do much good at all. On both occasions when mine gave up, I was unable to move the piston with a hammer and a lump of aluminium anyway, so if the same has happened to yours, it'll probably be similarly banjaxed.
 
:( Ive seen some on ebay for £30 each from a scrap vehicle, but there is no guarantee they will be in better condition than mine are. How much would i be looking at for a new callipers fitted from a garage roughly?

I'll have a look tomorrow anyway and see what condition the callipers are in.

I'm just glad the burning smell wasn't coming from the engine bay :D.
 
Well when I asked Honda for a quote for new calipers, they wanted £315 per caliper + VAT and that was without fitting. Your calipers should be an awful lot cheaper than that from Ford though, so I can't comment on price (my local Honda garage always quoted higher than almost any other I've heard of for parts).

You're right about the used calipers from a scrapped car. I bought my first replacement pair from a scrapped CTR due to not being able to find a refurbed or new pair in a hurry. One of them failed just over a year later. They looked like they'd seen better days when I received them. Refurbed calipers are probably the best way to go for price (if you can find some), and they're as good as new.
 
Janesy B said:
Brakes are binding, you'll need to get them readjusted. You'll probably need new pads too now.
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You can't adjust binding out of brakes, it's caused by a mechanical fault. If brake shoes are dragging you can adjust that out, and if the handbrake mechanism is set incorrectly you can adjust that too.

If you are going for "new" calipers I'd look at somebody like Big Red or EBC who do reconditioned units (they literally are as good as new) at reasonable rates.
 
Mark A said:
Would this still allow the car to roll freely?
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What can happen is that the brakes are only binding a little when cold, allowing the car is roll quite freely and with no obvious problems. As the brakes heat up the disc expands and binding gets worse, leading to more heat, more binding etc. Basically a thermal runaway condition. I've had the front brake on a bike suddenly lock due to this.

There are other possibilities:

1) The new pads may be a little oversize, or more likely the fitter didn't clean up the carrier which holds the pads. These often get rusty, so it can cause the pad to jam within the carrier, giving the same effect as a sticking caliper. This should be obvious if you disassemble the brakes as the pads should be quite free to move within the carrier.

2) Flexible brake hoses can collapse internally, preventing fluid flow in one direction which would give the same symptoms. This is extremely uncommon, but it can happen.
 
Thanks for all the replies :).

Just been out and jacked the car up and the wheel doesn't spin (not sure if its supposed to?). I can turn the wheel easily by hand but there is definite resistance there and a scraping sound can be heard. The brakes are cold as i haven't driven the car today (bar turning it round quickly so i could get the jack on a flat surface) and as someone mentioned they will get worse when they heat up.

Looking at the carriers they do look a bit rusty and not very smooth. So i could try and clean them up and put a bit of copper grease on? I have a feeling I'll be needing new callipers though :(. I'll check out the reconditioned ones people have mentioned. Going to let my dads new mechanic have a look at it as i don't trust the last garage, plus they ripped me off £57 just for fitting the pads and discs i supplied so god knows how much they would charge to sort this out.

Regarding the wheel bearing, wouldn't this make a strange noise while the car was driving? I don't remember the wheel its self feeling hot, it seemed to be just the disc.
 
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Just had a proper look and took the wheel off. The carriers look pretty corroded so i took a wire brush to it to clean it up a bit and put some copperslip grease on. The wheel is now turning but this is probably due to me trying to remove the calliper. Its deffo the pads binding as i couldn't even get the calliper off.

Could it possibly be that there is too much brake fluid in the system? The garage must have topped the brake fluid up and its spot on the max level line. I was thinking that this coupled with the brand new pads and discs could be making it touch the disc slightly? Or would that be far to easy :D.

If it was the carriers that are knackered, would that be cheaper to sort than if its the calliper? They dont look in great condition tbh.

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