Installing rebuilt rear calipers onto new rotors & pads

[TJC]

I also posted this question on the Mira boards because I have a friend coming over to help with my brake job today and I'd like to plot a solution before he gets here.

Anyway, I'm in the middle of this monster brake job (all calipers, all rotors, SS flex lines, master cylinder, & front wheel bearings). Although I bought a lot of parts from the regular Fiat suppliers, I got the rebuilt calipers (Beck/Arnley) and rotors (Raybestos) from RockAuto on the advice of a friend.

The rear calipers calipers came loaded, including wedges, clips, caliper bracket, and even pads. However, I can't get the caliper over the rotor with the pads installed. After re-reading the Haynes manual I have, I realized that I have to crank the piston down clockwise until it "seats" which I assume means until it stops. However, the piston was only part of the fitting problem. The caliper jaws themselves don't seem to fit nicely over the pads. I then noticed that the pads came with shims installed, yet the old pads I previously removed looked like they had them taken off. So, I removed them from the new pads, but the calipers still don't fit. The caliper jaw-to-pad interference does seem small and I MAY be able to get the calipers on if I bang away at them with a mallet, but I don't think it should be that tough, right?

On the advice of Jon Logan, I checked the thickness of the rear pads to see if the calipers were mistakenly shipped with the much thicker front pads, but they are indeed a lot thinner than the Ferrodo's I bought for the front semi-loaded rebuilds (the front pads have a total thickness of ~0.675" where the rears are only ~0.5". But, the rear rotors I got are exactly the same as the front).

So, has anyone experienced this problem and/or know what my options are to get these calipers installed correctly?

Also, should I be cranking that piston down until it stops? It's taking a LOT of turns just to move down only a little bit. Shouldn't they have been screwed down to the correct position when assembled from rebuild?

Any help would be appreciated, thanks!

[manoa matt]

It will be easiest to install in this order.

install rotor on hub, install spacer and wheel locating pins to hold it all together
Install cast iron brake caliper bracket on mounting bracket adapter
load pads into caliper mounting bracket and make sure they are snug against the rotor sides

You may need to place the caliper on the ground and with a large flat screw driver, a file, or flat bar stock push hard on the piston while screwing it in.

see this thread regarding the proper orientation of the piston face. http://fiatspider.com/f08/viewtopic.php?f=9&t=9090

Here is a picture of the stock front and rear pads. The front measures 16mm total including the metal backing plate, the rear measures 9.5mm total. http://www.flickr.com/photos/bigtimes_fiat/4448808002/

You will notice the rear pad has a nub in the backing plate. The piston face must be properly aligned so the nub slides in the piston face recess. See the last picture in the link from the other thread.

[TJC]

Thanks Matt.

Is that a pic of new rear pads?! If so, those look a lot thinner than the ones that came with my loaded calipers. And my pads are 0.48-0.5" (about 12mm) which is indeed a lot thicker than your 9.5mm. So, that explains a lot.

Thanks.

[manoa matt]

Yep, both pads are new

[TJC]

Yep, both pads are new

I think we found the problem. It was shipped with the wrong pads. That'll teach me for not buying from a Fiat vendor.

Thanks for the help.