Hi. I have a 1979 450SL and I recently bought new brake pads. The backs werent a problem to install, but I cant get the fronts in. I can't seem to expand the pistons far enough into the calipers to clear the width of the rotor with the new brake pads. The pistons "look" like their far enough in, but the pads still wont clear the rotor. Any suggestions? Thanks.

 

loosen the master cylinder cap to release pressure and the calipers should compress. Put a rag under master cylinder incase any brake fluid drips.

 

I'm certain that you already overflowed the master cylinder if you didn't remove fluid befor starting the job. I use a new turkey baster. I'm also certain this job has been completed but I will reply anyway. I always found if I put the old pad against the caliper piston and then use a C or bar clamp, I can squeeze the piston back flush to the caliper, then they will fit around the rotor with the pads on. This is also a good opportunity to bleed out old brake fluid while topping off with fresh Dot 4.