Removing ABS sensors on trailing arm - help!

[CBschnell]

Looks like I have screwed up but I‘m sending my trailing arms for blasting and I have removed everything except the sensors. I have tried everything but they will not budge. I thought it was just the top screw that held them in - is that correct? All recommendations appreciated - I have buggered them somewhat in trying to remove them so can’t just leave them alone

 

[dlknight]

Get some heat on the outside of the trailing arm.

I found that twisting them left and right whilst pulling eventually got them to come out in one piece.

If I recall correctly that is a sticky out piece (ear) that the bolt goes through, try gently knocking it around to rotate it with a punch / drift and small hammer.

Also lots of penetrating fluid from underneath.

Perhaps a good clean around the them with a small brush as well to remove any crud and allow the penetrating fluid to seep into any gaps.

EDIT: Blasting? I hope that isn't sand blasting, aluminium is soft and the abrasive will ruin the surface of the arms. I had mine vapour blasted which is a much gentler process and safer for aluminium.

 

[CBschnell]

Thanks - I have done all of that without any success. I think I will try with the sensor in a vice, and to twist and pull the trailing arm - I can't tell you how much WD40 I have already used!
Yes it will be vapour blasted - just had other pieces done.

 

[scam75]

I have no experience of removing the rear ones, however I have had recent experience of the front ones. I removed the screw and got it started by bashing the eyelet until it moved a little. It was a fight, eventually got mole grips on it and was able to work it out that way. It may still have worked but it was definitely worse for wear, a bit mis-shapen and generally looked a bit beaten up. The best way to remove them is to knock them out from the inside, which could have been done by stripping off the brake set-up. Not sure if you have access on the rears that would allow this, I'm guessing not or you would have surely tried that with the arm being off the car.

Somewhat tellingly, I was unable to locate a second hand part when I needed it, as most end up worse for wear getting removed. They do get quite attached to their surroundings and aren't happy about being asked to come out!

Also, your original parts, will have metal cylinders that grow with years of corrosion, bonding firmer on to the hub. New parts from Porsche are plastic cylinders which should avoid this issue. However, my brand new plastic one would not go into my hub at all! Ended up getting a fairly decent, 2nd hand, metal one, and it popped straight in no bother. Make of that what you will. Porsche would not entertain me for a refund as it's special order part, and wouldn't take it back as faulty. Maybe my hole wasn't large enough (!), but why did the metal type fit and not the plastic one?

Anyway, I digress, just adding my recent experience. Good luck getting it out, you will struggle to get a used replacement, and they are £180 each new from Porsche! Well, the fronts are anyway.

Edit to add - fronts and rears are different, longer prong and shorter cable on the fronts, just in case you have to source replacements!

Cheers

Stuart

 

[CBschnell]

Thanks for the detailed response. These little buggers would not shift at all. As you mentioned they were really bonded. I found a post on Rennlist for 911s - similar issue. And it worked!
it was right up my street because it meant destroying the sensor - for once I could do it on purpose! The short version is drilling around the magnet,
removing magnet and surrounding copper. Then I used a drift to hit from underneath - the bearing is out so I could access it. That broke the bond and it came out easily. It may have just worked tackling it from the bottom in the first place.
I know the Porsche sensors are expensive but I did see some aftermarket sensors, has anybody used those?

 

[scam75]

I found some aftermarket stuff, for the fronts, not rears. It looked very much like (I think) Fiat Punto or Brava or something like that fronts were the same sensor, but would have needed the plugs changing over, they were £15 though! What put me off eventually was that they are sided, whereas the 944 ones are not sided. So the wire goes up the way from the hub, the Fiat ones were sided and either went 90 degrees left or right, so may not have cleared the hub to seat properly. That's when I pulled the plug on a new one from Porsche, just checked and it was £150 inc. vat with discount. It didn't fit though!!

Stuart

 

[dlknight]

Just checked for you -

Part number for rears is 94460640102...

Price is an eye-watering £168.55 inc VAT

You should be able to get 10% off that if you are either a) a member of PCGB or b) a member of Porsche Classic

This was discussed a few years ago over on tipec, you may be able to get a cheaper sensor with the Bosch part number, but may have to extend the lead.

Porsche Enthusiasts Club Forum • View topic - ABS Sensor!? (tipec.net)

Info
https://www.bosch-automot...l/-/product/0265006142

https://www.mister-auto.co.uk/abs-senso ... 5-006-142/

they were also fitted to the 964 from 1993, so you can use that as a search as well 944 606 401 02

they are all pretty much the same thing a Hall sensor, its just the package that changes,

so the one you are looking for might be 0 265 006 142, but the next number 0265 006 143 might not be for the 944 because the lead is 20mm longer but has the same sensor and plug.

so just start searching for number close then look at the pictures, you might find something with the same sensor but different plug, time to chop off the plugs and get the soldering iron out.

anything that better than the £152.00 genunine Porsche price is a saving and as the parts get harder to find you have to start thinking laterally to keep it all running