Please bear with me as I'm not trained and I only have a smidgen of mechanical common sense.
If I compress the caliper, aren't I squeezing the pads against the rotor? Maybe I'm missing a step here. The lip can't be more than 1mm.
1. Lift car
2. Remove wheel
3. remove the 2 bolts that fasten the caliper to the "hub?" "axle?" "thingy?" NOT the 2 bolts that hold the caliper together.
4. Then remove the caliper assembly from the rotor. Right?
Please tell me you have jack stands under it first. What you are dealing with is the section of rotor that the pad does not contact. This builds up rust over time & now the "pads" are underneath this crud. You should be able to tap the caliper off with a soft or dead blow hammer. I don't want to sound rude, but when it comes to brakes they are your life. If you don't fully understand what you are doing take it to a shop. If you twist the rubber caliper hose & crack it you might not know until the pedal goes to the floor.
Rubber mallet or deadblow is a good method, just be gentle, you're just trying to coax it gently over the lip. as you do, the pads will start to compress the cylinder, and eventually you'll be able to work it off.
I would suggest installing one of your caliper mounting bolts, and then tapping to rotate the caliper off the rotor, pivoting on the pin you just installed. That way you don't risk knocking it completely off and potentially tweaking the hose. If I'm just doing a pad replacement, I try to only take one pin out and rotate the caliper off. Lots of high-end kits are specifically designed to work that way. If you've got a significant lip on your rotors, you might think about going ahead and replacing them, though.
Brakes are serious, but they're not rocket science. Make sure you have a Chilton's manual or other reference, and take your time. FWIW, the guys doing brakes at a lot of the commercial shops aren't the sharpest pencils in the can. If you take your time and do it right, you WILL do a better job than you will get in a shop. Best tool to have in your kit s good brake part grease--clean and lube your pins/mounting bolts, and all the places where your pads slide on the calipers. Biggest thing I've seen to cause modern disk brake setups to fail is seized moving parts, that weren't properly greased.
Post up pics if you get stuck.
EDIT: Just re-read your second post... You have 4 bolts on the back side of your caliper. Two hold the caliper to the mounting bracket, and two more hold the bracket to the spindle or axle. The two you want to be removing are the smaller of the pairs, that hold the caliper to the bracket.
IF you're changing your rotors, then you'll need to remove the bracket as well.
I re-read my last post and I made myself sound a lot more stupid than I really am. I have more mechanical common sense than I indicated. I guess I was frustrated.
So, it really is as unsophisticated as I thought. You just tap the caliper off the rotor. That is the first conclusion I came to. I just thought there might have been another way that was slicker.
The rear rotors had the worst lip. The front ones were easy. The job is done and it went well. The brakes operate fine and I'm happy with the result.
I'm not a rocket scientist, but I'm not dumb either. I used jacks. What I'm just trying to understand are the tips and tricks of the better mechanics out there. Usually it leads to a better tool, but I know there are different steps, order of steps, or thinking outside the box.
I fully understand the importance of not twisting the brake line. I had a small stool next to the hub for when the caliper came off the mounting bracket. I used it to support the weight of the caliper. I also fully greased every contact point.
One more thing: On the pads in front, there were two retaining pins for each pad. Comparing the old stock pads to the new aftermarket ones, I noticed on the new ones that the nipple holding the pin to the pad was not a great design with the lip of the stack ones. I had to VERY gently position them into place once the pad was in the caliper. Subsequently, A couple pins on the aftermarket ones easily pulled off when trying to mount them. Hopefully that is not too much of a problem. I'm thinking I may get premature wear on those pads at worst. Maybe someone could chime in on that?
No worries! I have a lot more appreciation for folks that come on here UNDERstating their abilities than those who OVERstate them!
I guess it's been too long since I've done brakes on an S197, but I'm having trouble understanding your question about the pins... I realize you've got it all buttoned up now, but pics always help.
You just need to compress the caliper piston(s). I have not done brakes on my 08, but say on a Fox...
Simply put a c clamp from behind the caliper to the outer pad and slowly compress. The piston will go back into the caliper bore, and the pads will have some play between them and the piston. It should get you enough room to slide the caliper/pads off the rotor.
Same process as putting new pads on, when the new ones are thicker than the old worn ones.