Sticking caliper

EmilysDad

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It's annoying when you get pads fitted & within a few months they're like this o_O especially when you paid through the nose & supplied OE pads.



Cleaned up the calipers & fitted Mintex this morning between showers..... we'll see what happens.
 

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my front pads (with merc logo) were stuck in ways that is hard to believe possible.
no joking it took me 2 hours on one caliper to get the pad to move a few thou

in the end 6 hours of fighting to get the pads out on one side.... only to find one of the eight ( 4 piston calipers) was not going to go back for anyone... with two dust seals gone on other pistons shortly later I was £600 poorer

and that bargain price was thanks to the great guys at Grangemouth, if it was drive in, drive out at main dealer I think we'd be the wrong side of 2k
 
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EmilysDad

EmilysDad

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Fortunately there are only 2 pistons on my front calipers & just one on the rears. I easily pushed the piston fully home on the offending caliper using just a screw driver against the caliper while it was still built up. I cleaned up the contact areas a week or so ago while the pads were on their way

I could still do to look at a front caliper as the wheel is still dragging slightly
 

Westheath

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Change the caliper.

You will just burn out the pads and disc again.
 
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Change the caliper.

You will just burn out the pads and disc again.

Would you (on your own car) even after cleaning up the contact faces of pad/caliper? Are you thinking sticking piston or sticking pads?

The discs are actually on their last legs anyway ....
 

Mark A

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More likely to be a sticking piston. You can get replacement callipers for reasonable money from brakeparts.co.uk or even bigred.co.uk.

Both will also supply replacement pistons and seal kits if you are that way inclined.
 

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I used Bigg Red last year to refurb a sticking rear caliper...£50.
 

DREAMER NO2

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Emilysdad Change caliper never .. I would be back to the place that fitted them .Looks like they are more than 2 years old to me . The top 2 are over two years old .Mine have been in 4 years and are in better condition than those.
 
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Emilysdad Change caliper never .. I would be back to the place that fitted them .Looks like they are more than 2 years old to me . The top 2 are over two years old .Mine have been in 4 years and are in better condition than those.

They were fitted around Easter time during Beast from the East II. It was freezing, hence me getting someone else to do them. Once burnt .....
 

Westheath

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Emilysdad Change caliper never .. I would be back to the place that fitted them .Looks like they are more than 2 years old to me . The top 2 are over two years old .Mine have been in 4 years and are in better condition than those.

Errrmm .......................... the top pads in the picture are in that condition due to over heating @+250' constant.

imo
 

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brianbrian

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Emily's Dad,Those pads have done a big mileage, what were the disc like when the pads were fitted. I service ours every 5000 on a nice day, do you?
 
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Emily's Dad,Those pads have done a big mileage, what were the disc like when the pads were fitted. I service ours every 5000 on a nice day, do you?

Both sets have done the same mileage .... ;) they were from each side of the car. As above, they'll need changing sooner rather than later.
I have to admit that this car has seen the least attention from me than any other car I've owned ... I've never really gelled with it as I have other cars. Other's have serviced it when the the car has asked for it :oops:
 
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I would never let my pads wear that thin, should have been changed long ago.

Are you serious? I don't make a habit of it myself. As said, they were only changed a few months ago ... one side is as new & the other isn't. There hadn't been a problem with the set that came out so wtf would I have suspected there'd be a problem with the new pads? And they are only as worn as the sensor first 'sees' the disc
 

Submariner1

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Fortunately there are only 2 pistons on my front calipers & just one on the rears. I easily pushed the piston fully home on the offending caliper using just a screw driver against the caliper while it was still built up. I cleaned up the contact areas a week or so ago while the pads were on their way

I could still do to look at a front caliper as the wheel is still dragging slightly

If the piston moved back easily, and you cleaned the contact areas. I wonder whats causing the slight drag?

I have seen some non MB pads have problems in a caliper, even though they looked and roughly measured the same.
I luckily spotted a pin hole tear in one piston boot.
Fortunately the piston was still totally free, and lovely chrome shiny.
Never the less I still checked the pad thickness comparing inner and out against the corresponding other side ( if that makes sense ) after fitting new pads.
Thankfully no drag and they are still even after 3 checks and a year.

I would say do the same ... but if one side drags even post clean up, then to me thats an issue; as it could wear exponentially when it gets really hot.

Having spent hours cleaning and painting mine, in future I would go the refurbish route like big red etc.
Great job for not a lot.

Despite being totally free, hardly any wear, I still have the tinyest bit of brake squeal when you just touch the brakes when very hot. The weight of your foot dispels it!
I suspect its the oldish disks.
 

Westheath

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Its not just the caliper piston that causes the problem, the caliper pins seize as well.

They should be replaced/serviced at the time of the pad change.
 
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EmilysDad

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If the piston moved back easily, and you cleaned the contact areas. I wonder whats causing the slight drag? ...

They do now after I cleaned up the contact faces of the caliper ... but I'm not sure the bloke thatoriginally changed my pads did so though.
 
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EmilysDad

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Its not just the caliper piston that causes the problem, the caliper pins seize as well.

They should be replaced/serviced at the time of the pad change.

Which is what I did ... all nice & shiny & greased up
 

Submariner1

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They do now after I cleaned up the contact faces of the caliper ... but I'm not sure the bloke thatoriginally changed my pads did so though.

My friend had his Audi’s front brakes discs and pads changed at his main dealer.
The calipers looked filthy, I noticed the flat parts on the caliper, what I call the sliding surfaces were caked in crap. Based on how clean the metal backing plates of the new pads were, I am positive they werent even wiped off.
Assuming brakes on a “fast” Audi ‘RS thingy’ with big exhausts, uses the same concept as MB and Porsche; I just thought wow ... your mechanic must have taken the calipers off to remove those discs?, and couldn't even be bothered to clean up the calipers, let alone the sliding surfaces or the silver pins.
So maybe you are right and some mechanics dont bother!

Being a novice I meticulously cleaned all those surfaces and the silver pins with brake cleaner, and regreased with that silver MB brake paste, being a tad OCD, I even bought new spring clips as they were a tad rusty.
 
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EmilysDad

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... I noticed the flat parts on the caliper, what I call the sliding surfaces were caked in crap. . ....

I've just replaced the front pads on EmilysMum's Citroen C3. The 'sliding surfaces' all had a stainless steel liner clipped to the caliper ... I thought it was a good idea
 

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