A 52 3600 would have Huck brakes if stock. There are two adjusters on the wheel cylinder, so you would need to loosen both of them. And one you pull down to loosen and the other you pull up to loosen. The service manual says clockwise looking at the end of the cylinder, so counter-clockwise to loosen each end. You might also open the bleeder valve in case there's fluid trapped in the cylinder from a collapsed brake hose.
Is there on adjuster on bottom and on on top ? I appears it is the back shoe is sticking , going to loosen bleeder and find other adjuster , will let all you know how it goes 👍TY
