Did I seat this caliper properly? Uneven disc wear? with new pads

Submariner1

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OK did the left front side Caliper and brake pad and drove 3 miles ... no squeaks, it braked straight all good? Or so I thought.
Then this morning, I noticed the wear was uneven ... it had failed to rub off the rust on most of the lower half.
IMG_4596.JPG
As there was a shinny band near the hub. I would normally assume it was just accomodating the uneven wear of the disc and possiblly wearing off some of the new brake pad on a higher section (near the lip by the hub). Note the lip was just within MBs tolerance.

I ask the question as in truth I did put too much thread locker on the 2 securing M14 bolts, and I just wondered when inserting the bolt; could some thread locker have got between the mating surface of the caliper and the steering knuckle, i.e. So the caliper didn't seat perfectly flat to the steering knuckle?

I assume it did seat properly, because of the shiny worn lower band by the hub. And at 180 Nm probably would have squidged out any threadlocker.

Here is a pic of the other RH side's disk, where I know didn't overdo the thread locker.
IMG_4595.JPG
But this right side had done 25 miles more. And even then there is also a slight band of unworn disk, in vaguely the same area.

OK, so as to compare like with like ... I drove 8 miles more, and the left (questionable side) now seems to have settled in/worn itself in.
IMG_4597.JPG

Is it safe to assume the caliper is seated properly, and it was just the uneven disc, or the pad aligning itself by wearing to the lipped disc?

Apologies for this basic question, but when money was plentiful .. I just had the dealer change pads and disks at the same time. So no experience of doing this stuff myself or using partially worn discs.

Does the Pad automatically align itself if the caliper is not seated perfectly squarely?

Or are there any tell take signs if its not seated squarely, like noises or steering abnormalities?
So far seems to be fault free. Brakes straight, albeit not done any vicious braking until the new Pads are worn in.
 

Wighty

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New pads on the rear can take a while to bed in , especially as drilled discs tend to create more grooves on the surface . Also rear brakes only come in to play when you brake harder , I think it's something like 70/30% front to rear . They will settle down in a few hundred miles , although my Clk too a year to fully contact the whole rear disc .
After a couple of days just jump on the anchors more :) ( see what I did with your username :geek:)
 
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Submariner1

Submariner1

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New pads on the rear can take a while to bed in , especially as drilled discs tend to create more grooves on the surface . Also rear brakes only come in to play when you brake harder , I think it's something like 70/30% front to rear . They will settle down in a few hundred miles , although my Clk too a year to fully contact the whole rear disc .
After a couple of days just jump on the anchors more :) ( see what I did with your username :geek:)

Thanks, it was actually the front left but same applies apart from the distribution.
And yes I did
Peter
 

LostKiwi

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You worry too much Sub! Give it more than 28 miles to sort itself out. If it was like that after 150 miles then its a matter for minor concern but no pad will settle into the contours of the disc after only 28 miles.
Incidentally when discs are rusty do not treat them harshly as the structure of the metal can change and create poor braking.
 

L John

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You worry too much Sub! Give it more than 28 miles to sort itself out. If it was like that after 150 miles then its a matter for minor concern but no pad will settle into the contours of the disc after only 28 miles.
Incidentally when discs are rusty do not treat them harshly as the structure of the metal can change and create poor braking.

Totally agree but I wish more people were like Sub instead of people driving cars that have dangerous defects but they drive in ignorance.
 

L John

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If the calipers and pads are fitted correctly and the disk is above the service limit they will bed in quickly especially under hard braking.
Whenever new pads are fitted to used disks they will never contact fully until they have bedded in and that takes some use before optimum braking returns.
 
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Submariner1

Submariner1

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You worry too much Sub! Give it more than 28 miles to sort itself out. If it was like that after 150 miles then its a matter for minor concern but no pad will settle into the contours of the disc after only 28 miles.
Incidentally when discs are rusty do not treat them harshly as the structure of the metal can change and create poor braking.

Thanks
I was only worried becaus I knew I put on too much threadlocker and wondered if it had got some between the lower caliper and the steering knuckle. But the fact it had the worn band near the hub meant to me it was just a wearing In thing.
Thanks for the rusty tip. Didnt know that.
 
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Submariner1

Submariner1

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Totally agree but I wish more people were like Sub instead of people driving cars that have dangerous defects but they drive in ignorance.
Thanks
I dont do brakes normally but in this case I am painting the calipers, so when I saw 2 split caliper dust boots, and discovered MB have pulled the seal and piston kit. If water got in and corroded the pistons then it would mean 2 new calipers ouch!
(Note the Indy is a 70 mile drive) hence got sucked into this.
To change the boots you need to take the caliper off, and as the pads were nearly worn down, you get the drift.
A simple paint job just expanded and expanded well outside my comfort zone. But learning lots.
Apologies to those who know all this stuff.

And yes I am pretty OCD re brakes ... as a student I had a TR6 totally blow a master cylinder coming down the hoggs back near Guildford. The handbrake on those was utter crap! And finally only stopped the car by grinding the rims against the kerb.
Truly terrifying...
the joke is I dont even change brake fluid .. get my Indy to do that.
And to make you really laugh the ****** caliper paint reacted with the clear coat, so have to re do all that. :(
 

ernieh

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And yes I am pretty OCD re brakes ... as a student I had a TR6 totally blow a master cylinder coming down the hoggs back near Guildford. The handbrake on those was utter crap! And finally only stopped the car by grinding the rims against the kerb.
Truly terrifying...

Hoggs Back....is that where Mike Hawthorn was killed?

Ernie
 


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