ABS sensors.

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HPFirenza
Joined: Tue 29 Jun, 2010 14:49
Posts: 64

  Z3 roadster 1.9
Location: Lytham St Annes

ABS sensors.

Post by HPFirenza »

I am trying to remove the front ABS sensors on my 1999 Z3 E36. When the bolt is removed they are really rock solid, but should the sensor turn in the hole or is there a locating groove in the hole so the sensor can't turn so that you can only lever them out. Hope that makes sense.
Wookee
Joined: Thu 10 Dec, 2015 19:45
Posts: 166

  Z3 roadster 1.9i
Location: Herts

Re: ABS sensors.

Post by Wookee »

I did my rears recently and they put up a good fight meaning I couldn't get them out in one piece :(. There is no locating groove, they just seize solid due to where they are and exposure to the elements.
Alan W
Joined: Thu 20 Jun, 2013 10:56
Posts: 670

  Z3 roadster 2.8
Location: Bexley, Kent UK

Re: ABS sensors.

Post by Alan W »

Does it help if you put the new ones in with a bit of copperslip? Just curious anyone?
1999 facelit Z3 Roadster 2.8 Auto in Cosmos Black aka 'Gloria'
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Gazza
Joined: Tue 04 Oct, 2005 20:58
Posts: 9521

  M roadster S54
Location: Romford Essex

Re: ABS sensors.

Post by Gazza »

You could try copperslip or similar but the sensors are quite a tight fit.
Gazza

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therealdb1
Joined: Tue 25 Jun, 2013 21:47
Posts: 263

  Z3 roadster 2.0

Re: ABS sensors.

Post by therealdb1 »

No there is no locating groove and when freshly installed they can be wriggled side to side slightly.
However it is a common problem for them to seize in the hole.
A technique I have used with 50/50 success is to lift the car high enough to get a bar of aluminium (soft but stiff and non-magnetic) of slightly smaller diameter than the sensor and tap it out from underneath with a club hammer. One came out and was reuseable the other was so tight it was destroyed.
When you come to fit new ones do not just put them straight back into the holes otherwise you will have the same trouble all over again fairly quickly. Make sure you clean all traces of rust and brake dust from around the area. I used a bit of emery cloth followed by some fine wet and dry paper and a final buff up with a small circular wire brush that went down the bore fitted in a Dremel minidrill.
Once you are happy that everything is clean you can lubricate the sensor and hole and you should then be able to push it in and out with finger pressure.
For lubrication I prefer silicon grease like plumbers use for the plastic parts as it does not affect the plastic unlike some petroleum based greases but I put a liberal coat of Copperslip on the thread of the securing bolt.
Having been through this it is best to treat this procedure like a service item so each oil change pop out the sensors, clean and relubricate and they shall not trouble you again.
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HPFirenza
Joined: Tue 29 Jun, 2010 14:49
Posts: 64

  Z3 roadster 1.9
Location: Lytham St Annes

Re: ABS sensors.

Post by HPFirenza »

Thanks for the replies. I assume therealdb1 you are talking about the rear sensors and not the front ones, is that correct.
therealdb1
Joined: Tue 25 Jun, 2013 21:47
Posts: 263

  Z3 roadster 2.0

Re: ABS sensors.

Post by therealdb1 »

Actually I've confused myself!
The last ones I did were on my Volvo which drop in from the top on the front wheels. :dunce:
However the technique I describe still holds but you shall have to remove the brake disc and possibly the hub too.
It depends how much you want to save the sensor. Why are you trying to remove it? Is it faulty anyway?
The quickest way to get a siezed sensor out is to drill it out from the back but obviously you are committed to a new sensor at that point.
Wookee
Joined: Thu 10 Dec, 2015 19:45
Posts: 166

  Z3 roadster 1.9i
Location: Herts

Re: ABS sensors.

Post by Wookee »

HPFirenza wrote:Thanks for the replies. I assume therealdb1 you are talking about the rear sensors and not the front ones, is that correct.
I certainly was. I did copperslip them after cleaning the holes with a dremmel just in case they were faulty. If they stay in there for some time I can't see the copperslip help getting them back out as it is a very tight fit.
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HPFirenza
Joined: Tue 29 Jun, 2010 14:49
Posts: 64

  Z3 roadster 1.9
Location: Lytham St Annes

Re: ABS sensors.

Post by HPFirenza »

Anyone used aftermarket sensors and would you recommend them, as they are a lot cheaper than BMW original parts. Also if I have to drill out the sensor I assume the front disc has to come off but do you need to take the hub/wheel bearing off, from photo's i've seen it's hard to tell.
Wookee
Joined: Thu 10 Dec, 2015 19:45
Posts: 166

  Z3 roadster 1.9i
Location: Herts

Re: ABS sensors.

Post by Wookee »

HPFirenza wrote:Anyone used aftermarket sensors and would you recommend them, as they are a lot cheaper than BMW original parts. Also if I have to drill out the sensor I assume the front disc has to come off but do you need to take the hub/wheel bearing off, from photo's i've seen it's hard to tell.
I put aftermarket ones in my rear and the same (German) company sell the front ones for £20 a pair link below. I've never looked at my front ones but having a look at the RealOEM diagram they just seem to 'pull' out from the inside of the hub carrier :shrug

http://www.ebay.co.uk/itm/2x-ABS-WHEEL- ... Sw1S9Wc8~X
bertiejaffa
Joined: Fri 26 Jul, 2013 09:28
Posts: 1733

  M roadster S50
Location: Manchester

Re: ABS sensors.

Post by bertiejaffa »

Wookee wrote:
HPFirenza wrote:Anyone used aftermarket sensors and would you recommend them, as they are a lot cheaper than BMW original parts. Also if I have to drill out the sensor I assume the front disc has to come off but do you need to take the hub/wheel bearing off, from photo's i've seen it's hard to tell.
I put aftermarket ones in my rear and the same (German) company sell the front ones for £20 a pair link below. I've never looked at my front ones but having a look at the RealOEM diagram they just seem to 'pull' out from the inside of the hub carrier :shrug

http://www.ebay.co.uk/itm/2x-ABS-WHEEL- ... Sw1S9Wc8~X
Hi Wookee - do you have the link to the rear ones you fitted?
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Wookee
Joined: Thu 10 Dec, 2015 19:45
Posts: 166

  Z3 roadster 1.9i
Location: Herts

Re: ABS sensors.

Post by Wookee »

bertiejaffa wrote: Hi Wookee - do you have the link to the rear ones you fitted?

Her you go

http://www.ebay.co.uk/itm/371505800139? ... EBIDX%3AIT
bertiejaffa
Joined: Fri 26 Jul, 2013 09:28
Posts: 1733

  M roadster S50
Location: Manchester

Re: ABS sensors.

Post by bertiejaffa »

Cheers fella
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