Front brake rotor not centered

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CA124
Posts: 25
Joined: Tue Mar 31, 2015 6:09 pm
Your car is a: 1969 Fiat 124 Sport Coupe

Front brake rotor not centered

Post by CA124 »

New guy here.

I'm in the process of overhauling the brake system on my 124 coupe and came upon a problem. The front rotor is not centered to the brake caliper bracket and it doesn't seem right (see attached pic), I then checked to see if there was any play on the hub but that felt fine - no play. I then checked to make sure I had the correct rotor for my 124 and it was correct, I even checked the old rotor for comparison and they both matched.

Anyway I put everything back together and went out for a test drive and sure enough there was some periodic metal on metal rubbing when driving. Got the car back to garage and take a look again just incase I missed something. Checked to make sure there wasn't any spacers between the upright spindle and the caliper mounting bracket - there wasn't so crossed that off my list. Next I checked the hub again just to make sure everything was seated properly - it was.

I'm completely lost on why the rotor is not centered. I thought maybe the caliper mounting bracket was not the correct 124 and perhaps they were from another fiat model but they checked out to be the right one. I checked to see if maybe the hubs were not the correct ones but they seem correct to me - they had a number stamped on them 08658.

Any help will be much appreciated
Thanks,
Ed

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DieselSpider
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Joined: Wed Dec 24, 2014 10:21 pm
Your car is a: 1978 124 Spider with Isuzu Turbo Diesel

Re: Front brake rotor not centered

Post by DieselSpider »

The caliper slides on the mount and the brake pads center it on the rotor. Your condition will usually occur if the inner pad is thinner than the outer/worn out or missing.
AriK
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Re: Front brake rotor not centered

Post by AriK »

Check your old rotor to make sure a piece is not forgotten in there for seating against your spindle.
Ramzi

Re: Front brake rotor not centered

Post by Ramzi »

Pad wear will not cause the rotor to be off set in relation to the caliper holder. The only time Ive ever seen this is when a new hub was machined incorrectly. But judging from the photos, the hub was not replaced. Did you replace the wheel bearings? Also make sure that everything is seated correctly.

Ramzi
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4uall
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Your car is a: 1980 Fiat Pininfarina Spider 2000 F.I.
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Re: Front brake rotor not centered

Post by 4uall »

Had a similar issue and it turned out that my new rotor was warped just enough to rub :shock:

http://fiatspider.com/f08/viewtopic.php ... ilit=rotor
Jay

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azruss
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Re: Front brake rotor not centered

Post by azruss »

looks to me like a classic case of the slider being stuck. This is forcing all the wear on the inside pad and it looks like the inside pad is getting down to the metal. Look at both inner and outer pad to see if they show the same wear. If one shows a lot more wear than the other, then you need to clean and lube the slider track on the caliper and the wedge.
DieselSpider
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Re: Front brake rotor not centered

Post by DieselSpider »

Can see better on the office computer that the caliper is not in place so I would start by checking the inner bearing and cone being a correct matched set and in place.

How much of what you now have is new to the car?
CA124
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Joined: Tue Mar 31, 2015 6:09 pm
Your car is a: 1969 Fiat 124 Sport Coupe

Re: Front brake rotor not centered

Post by CA124 »

Thanks for the responses.

I documented how everything was put together before I disassemble the front brakes.
I bought new brake pads, new hoses, re-conditioned calipers, and new rotors then proceeded to put everything back together the way it was. When I noticed that the rotors were not centered I checked my notes/images of the original assembly and also noticed that the old rotors were not centered to the caliper bracket.
To confirm this I re-installed the old rotors and they were fitting exactly the same way as the new rotors - off centered.

I then proceeded to track down which components were causing this off-centered problem. Check to see if there were spacers between the caliper mounting plate and the upright spindle - no spacers which is correct.
Next I checked the hub and it sounds like it's the correct hub.
Next I checked the caliper mounting bracket and they look like the correct one.

So which component is causing the off-centering???? They all seem to be the correct component.
CA124
Posts: 25
Joined: Tue Mar 31, 2015 6:09 pm
Your car is a: 1969 Fiat 124 Sport Coupe

Re: Front brake rotor not centered

Post by CA124 »

DieselSpider wrote:Can see better on the office computer that the caliper is not in place so I would start by checking the inner bearing and cone being a correct matched set and in place.

How much of what you now have is new to the car?
I'm planning to replace all front bearings for the hub. There were a fair amount of play on both the outer and inner bearings but i don't see that as the cause for the off-centering issue. The hub is seating correctly to the spindle with about 1/8inch gap on the back - see pic

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CA124
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Re: Front brake rotor not centered

Post by CA124 »

I should also state that when I bought the car the front calipers were pretty much stuck with only minimal movement to stop the car. Probably the reason I didn't hear any rubbing against the rotors since the brake pads were applying constant pressure on the rotors enough to push the rotors away from the caliper mounting bracket.
AriK
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Re: Front brake rotor not centered

Post by AriK »

I would have to assume that the PO installed incorrect wheel bearing components. Go ahead and change the bearings, hopefully you get to the bottom of this. Is your issue with both wheels? If not, compare the both sides.
CA124
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Re: Front brake rotor not centered

Post by CA124 »

AriK wrote:Is your issue with both wheels? If not, compare the both sides.
The issue is on both sides.

Anyone else have any thoughts while I wait for the bearings to arrive? :D
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toplessexpat
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Re: Front brake rotor not centered

Post by toplessexpat »

CA124 wrote:Anyone else have any thoughts while I wait for the bearings to arrive? :D
.... does it feel like you've got ABS? ;)
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4uall
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Re: Front brake rotor not centered

Post by 4uall »

Jay

Fiona
1980 FI 2000 Spider
ITZEBTZE

https://goo.gl/photos/eNKaX7hrXhBu9fmp6

FINN (FN-2187)
2014 Jeep Wrangler Sport
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CA124
Posts: 25
Joined: Tue Mar 31, 2015 6:09 pm
Your car is a: 1969 Fiat 124 Sport Coupe

Re: Front brake rotor not centered

Post by CA124 »

^ thanks Jay!

I like how this guy explains things. Very encouraging!
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