Working on the calipers on the 1991 560SEL. I'm using compressed air (brake caliper kit purchased from Kent at mercedes source). I placed a small board between the calipers then hit it with compressed air into a new meyle brake hose. Only one caliper moved.

Question, if I put the caliper back on the car and step on the brake pedal will it unstick the other caliper?

Attached Thumbnails

   

You can try unsticking it with the brake pedal, however if they're really that seized you may be better off with a reman caliper! You're going to have to tear that one down and rebuild it and hone the cylinders anyway.

__________________
Current stable:
1995 E320 149K (Nancy)
1983 500SL 120K (SLoL)

Black Sheep:
1985 524TD 167K (TotalDumpster™)

Gone but not forgotten:
1986 300SDL (RIP)
1991 350SD
1991 560SEL
1990 560SEL
1986 500SEL Euro (Rusted to nothing at 47K!)

Using brake hydraulic pressure is a lot more powerful than compressed air. The caliper doesn't appear severely corroded or otherwise not worth rebuilding. So yes, I would mount it on the car.

Push the free piston back in and insert a new brake pad on that side only. Leave the stuck piston side empty with no brake pad, or you can use a very thin worn down brake pad if you have one. The new brake pad will prevent the free piston from travelling much, and the air gap on the other side allows the stuck piston room to move. The brake rotor will prevent it from shooting out and making a mess.

__________________
1998 E300 turbodiesel

America's Rights and Freedoms Are Not The Enemy!

Should I use red, blue or green thread locker on this bolt?

Attached Thumbnails

   

This.

__________________
I'm not a doctor, but I'll have a look.

'85 300SD 245k
'87 300SDL 251k
'90 300SEL 326k

Six others from BMW, GM, and Ford.

Liberty will not descend to a people; a people must raise themselves to liberty.[/IMG]

You may be able to get it loose, but as said above, be perpared to buy a new caliper, anyway. If it it that stuck, it is stuck due to rust between the piston and bore, which means rust pitting.