ABS Sensor disc marks

[Jarfar]

Hi,

I am quite new to doing my own mechanical work on my van and recently was swapping out the rear brake calipers. I noticed what I thought was a disc with very small teeth as in a cog but full of grime. I noticed also this seemed to be where the ABS sensor monitored. So I tried cleaning up what I thought was the cog teeth. However, these cog teeth seem to vanish when cleaned with a wire brush. See attached video.

Is this anything to be concerned about? What is causing this to have grime that looks like a cog?

Van is a UK renault Master Mk3

Thanks in advance

[dingg]

Hmm ,some reluctor rings are manufactured in a plastic type of composite material, maybe yours is ,I don't know for certain, but its a distinct possibility that you have buggered it up with the wire brush if its made of that material

[Crudeoink]

Its possible the grime contained ferrous material that has settled within the magnetic field and is essentially making the field visible. I saw this with one of those magnetic GB symbols, after a long road trip small striations of dirt appeared and showed on the field lines on the surface

[Jarfar]

The ring\disc is made of metal because the wire brush revealed it. Are you saying the cog\teeth was plastic but has basically rotted away with grime?

[Jarfar]

dingg said:

Hmm ,some reluctor rings are manufactured in a plastic type of composite material, maybe yours is ,I don't know for certain, but its a distinct possibility that you have buggered it up with the wire brush if its made of that material

Thanks for your feedback - as a person new to doing my own mechanical repairs (quite enjoying some of it) I had never heard of a "reluctor ring". So this helped and I looked up ABS reluctor ring Renault Master Mk3. Found this tutorial in two parts. The youtuber has quite a scottish accent. It seems to show the cog like lines\teeth same as mine but new one is smooth metal so I am guessing mines is the same and is a smooth metal ring.


How can I tell if mine is still working though?

https://www.youtube.com/watch?v=WK6lhyEGKuo&t=...https://www.youtube.com/watch?v=dNl9VjuKwf8

This is an image of a new one it seems

Edited by Jarfar on Monday 5th October 14:47

Edited by Jarfar on Monday 5th October 14:54

[Jarfar]

Crudeoink said:

Its possible the grime contained ferrous material that has settled within the magnetic field and is essentially making the field visible. I saw this with one of those magnetic GB symbols, after a long road trip small striations of dirt appeared and showed on the field lines on the surface

Thanks for feedback - so do you mean the lines that look like cog teeth are created as lines by the magnetic field?