Decided to give the calipers a coat of paint in anticipation of the summer season…
Upon stripping the drivers front down to descale etc, I noticed that the slider pins are slightly different.
One is solid, while the other has a rubber sleeve on the end.
Any ideas why ??
Incidentally, also decided to change the discs and pads while i’m at it.
They should both have rubber boots on them and be free to slide in and out to allow the calliper to move.
If one does not have a rubber boot, and with the description of “solid” I would suggest that the absence on the rubber boot is likely to have resulted in the second, then the calliper won’t slide properly and certainly won’t release properly.
Were the pads that came out tapered by any chance?
Let me rephrase.
The pins are free to slide in the housing, and both of which have a fully intact rubber dust cap.
However, upon removing the pins from the carrier, one is solid steel along it’s entire length.
The other is steel for 50% of it’s length with a rubber section for the other 50%.
Nothing wrong with the pads other than only having about 30% left.
I’m only changing them now, so i don’t have to do it next year, and thought, if i do the discs at the same time, then they will probably see me out for the next 5 years.
I’m starting the nearside this evening, so maybe i’ll post a photo of the pins.
I know what you mean, had my MK3 front’s refurbished a short time ago which where the same, but as you no idea why
Ah, I have always assumed the one with the rubber sleeve stops chatter while the bottom one does not need it.
I would however advise not taking, certainly the top pin out, if it is sliding correctly as it is very easy to stretch the sleeve making it too big for the hole it fits in and therefore binding.
Nick…Sounds good to me
Looking at the nearside this evening and I was thinking exactly the same, that the rubber acts as some form of shock absorber.
With the amount of rust on the carrier, leaving the pins in situ wasn’t really an option.
My face looks like I’ve had a fortnight somewhere exotic there was that much rust.
So the one with the rubber’Collar’ is the top one?
I don’t really recall, i just marked the one which came out of the number 5 hole.
(5 was a casting mark on the carrier)
I seem to think that it may have been the bottom one on the nearside, but i wasn’t really paying too much attention as to whether it was top or bottom, just which hole it came from.
I’ve got a copy of the workshop manual here, and after 10 minutes of looking at it, I’ve concluded that the rubber-augmented slider pin goes on the bottom of the caliper, not the top. I still have no idea why.
As the caliper lifts, the shock is absorbed.
Push, pull, whichever.
I only asked because I thought the rubber collared pin was the bottom one,but it’s been a while since I stripped mine down, because the front offside caliper was sticking.
I cleaned up the pin and the cavity/hole as best as I could,used Red Rubber Grease to lubricate when rebuilding.
My NC has done 120k miles and I have owned it for approx 20k miles. In that time the only real problem I have had is with it needing two brake callipers.
Just the other day I got that familiar feeling of another calliper binding on. Checked the heat from the wheels and it was confirmed to be the front right.
In the past I have been away from home so had to go with garages recommendation of changing the calliper. But this time thought I would check the slider pins first. As you can see from the pic below this one (and the other one was the same) is quite badly corroded.
Gave the pin a good clean and a coating of Silicon Grease (which I understand is what you need due to the rubber boots). Both pins are now moving freely by hand which they weren’t doing before.
I will probably get new pins for this if this proves to fix the problem. But it does show that these pins should be inspected probably once a year on older cars.
PS. Rubber booted pin shown was the bottom one.
What that says to me is that the rubber bellows has been letting water in and holding it is for a significant amount of time and should have been picked up a long time before now.
What that says to me is the caliper pistons are sticking in their housings.