Incorrect discs?? HUH??

[XR6_4EVA]

Hey guys.

I spent saturday morning doing some car interior maintanance when i remember my rear pads need changing. SO...i went and grabbed some real nice high quality pads.

Once the wheel was off and the caliper open, i placed the pads against the rotor, but when trying to close the caliper back up again...IT WOULDNT CLOSE BACK UP SO I COULD BOLT IT BACK UP!!

I noticed that the width of the pads plus the width of the rotor was to much to allow the caliper to push back and line up to be bolted back up. So i thought how could this be possible. So i went and changed brand name pads,went from bendix to ferodo...ferodo's are a bit thinner, but still same issue!

So i thought about it, series 1 pads are totally different all together, so i didnt choose the wrong pads. So i looked at my old pads and noticed that at the very top of the pad, it seems to be wearing incorrectly. The original pads on there seem to be overhanging the disc a little and rubbing against that thin rusty outerlip. And then it hit me, series 1 discs were actually wider and shorter, series 2-3 are thinner and longer.

Which means, the previous owner, replaced the discs (front and back mind you!!) with series one discs, and figured that it was ok to do this, as at the time he would have placed the original already worn down thinner pads back in there, and the caliper would of closed back over just fine.

Thats annoying. Time for new discs, shock tower rubbers, diff, lifters...

Go the AU falcon!! nah seriously, AU's rule regardless.

[Peuty]

Being an ST shouldn't it have the premium brake package?

[XR6_4EVA]

Its just got the pbr's on there. by the look of things its had a crash requiring replacement of one or more discs and whatever else was destroyed...so whoever repaired it may of replaced everything incorrectly...as from what ive noticed so far, people dont know the difference between ST and series 2-3 standard. Besides AFF members of coarse.

[Peuty]

What does your Tickford build plate under the bonnet say? Is there any mention of premium brakes?

[Bolly]

You did make sure the piston was all the way back into the caliper??
Just a thought.
Cheers

[XR6_4EVA]

Originally Posted by Bolly

You did make sure the piston was all the way back into the caliper??
Just a thought.
Cheers

Thanks for the thought Bolly! however!

Regardless of how far the piston is pushed back into the caliper it wont actually slide over.

When un-screwing the bolt behind the caliper, the caliper flips open, the other bolt behind the caliper on the lower part is spring loaded and you can push the caliper to slide backwards away from you. You do this after placeing the pads on so that when you flip the caliper back over, the caliper can actually clear the top bolt and slide into place to be bolted back up.

So....in this situation, when i try flipping the caliper back over, you cant push the caliper to slide over the spot to bolt it back up, because the over all thickness of pad + disc + pad creates a perfect tight fit, and the caliper cannot be pushed away then back into position.

Since the piston side of the caliper is on the furthest side to you, it wont affect clearance in THIS CASE only, clearance in this case rely's on the width of the side closest to you, (space between inside of caliper and side of pad!)

Hopefully that makes sense.

Those of you that have done the pads a few times will know what i mean.

[JC]

Have you tried taking both caliper bolts out and putting the caliper back on that way. AFAIK, you couldn't run AU1 discs and AU2 calipers.

What part number did you buy? Have you checked it against the Bendix listing? IIRC AU1s used an DB1108, but AU2s were a DB1357 or something.

[sly]

Right again JC. IIRC the AU2/3 discs are thicker than the AU1's (16mm v's 10mm?) although the same diameter. The offset is also different from AU1 to AU2/3 IIRC, so discs from one will be around a centimetre misaligned with calipers from the other.

[XR6_4EVA]

Ahhhh...few things to investigate this weekend!

Thanks everyone.

If they are the same diameter, is it normal that 1-2 mm's of the bad is rubbing against the gritty outside lip of the disc?

Also, arent the ford calipers designed to just undo one bolt, slide open, replace pads, slide closed. Why should i have to undo both bolts?

[XR6_4EVA]

Sorry guys just want to bump this one back up there again. i can confirm i have the right discs on there, so why on earth can i not get the caliper to line up over the bolt hole. the caliper DOES fit over the pads, so clearance issue with the piston isnt a worry. Ill take pics this weekend...

[JC]

Originally Posted by XR6_4EVA

Sorry guys just want to bump this one back up there again. i can confirm i have the right discs on there, so why on earth can i not get the caliper to line up over the bolt hole. the caliper DOES fit over the pads, so clearance issue with the piston isnt a worry. Ill take pics this weekend...

With old pads, you can get away with undoing one bolt. With new pads, you may not get away with it (as you seem to be finding out). The only other option is that you are not pushing the calliper piston all of the way back into the calliper. It should end up flat with the rubber seal.

[XR6_4EVA]

Hey guys, just wanted to say that ive fixed the issue. On one side only, the pin that slides in and out of the caliper was siezed, thats why i couldnt get it to bolt back up. I had to use a ratchet gun to wack it out after 30 mins of torment, then sanded it to smooth and cleaned the buggers up and re-greased them. Good as new, and with the new pads, didnt have to un-do both bolts.

Thanks for everyones input!