MG TF LE 500 ABS Issue

Curry in a hurry?

Singing in the style of Johnnie Cash:
“ It burns, burns, burns…that ring of fire…that ring of fire! “

Earlier on in this thread, the number of teeth on the ABS rings was mentioned.
I have wondered about this difference because one of the faults I inherited with this car (an LE500) was a cracked ring, which caused the ABS to kick-in when braking at low speed.
All the rings were very rusty, starting to crack and were swollen to the point they were scraping the ABS sensors.
I have now replaced all the rings (and given them a good coat of paint to stop the rust killing them again) and also replaced the sensors.
However, the rings were pretty expensive (due to the number of teeth being different). If they had been as original, the cost would have been significantly lower.
I always thought that the ABS system monitored the difference between the wheel speeds and was not bothered about the actual speed.
So I think that I could have just replaced all the rings with the original type and the system would have worked ok.
Probably the number of teeth per rev effects just the actual speed at which the system kicks in (eg more teeth means more pluses per rev so the ABS starts to operate at a lower speed than if there were more teeth).

Hi, I've picked up 4 LE500 ABS rings as all of mine are pretty rough, out of interest, did you change them yourself, looks like a bit of a headache, I guess they have to be heated to fit?

You could try putting them in the oven to expand them with heat…………warning don’t try this when the leader of the opposition is in the house…..and I’m not talking about parliament!
The bit you’re trying to fit them on can be cooled in some dry ice to shrink them down, work quickly and they should go on easy…. Be organised and have a copper hammer to give them a tap if needed.

Make sure the mating surfaces are clean give them a going over with a wire brush and a rub with some emery cloth before you start.

I replaced mine myself. As I already had both subframes out of the car and all four corners stripped down, it was a fairly simple job.
If your car is still intact, the hardest job is to pull out the rear driveshafts which requires the hubs to be removed.
The fronts are easier to remove.
Then, as Cobber said, make sure the surfaces are nice and clean before fitting the new ones.
I did heat them with a hot air gun, but they cool down so quickly, they get stuck before the final position is reached.
Really you need a tube with a slightly bigger diameter than the rings to press (hammer) them on squarely, but I resorted to tapping (carefully) to the final position with a flat punch. Be carefull not to bend them.
After fitting, give them a good coat of paint. This doesn't effect the sensing but should stop them rusting again. I also coated the painted rings with Waxoil.
If your LE500 is anything like mine (was), everything was rusted together and very difficult to dismantle.
As the hubs are removed, this is a good opportunity to replace the wheel bearings if required.

I started my restoration project with a plan to just fix a couple of things like the ABS rings, so initially pulled out one rear hub and shaft. But that let me see just how bad the rest of the suspension was for rust.
So I took the decision to restore everything while it was still recoverable.