Pentax MX Aperture Coupling Ring Disassembly

Remove the lever cap. The cap is reverse threaded.

Lift off the advance lever.

Remove the collar beneath the lever.

Set the ISO to 100 and the shutter speed to 1000.

Remove one pin head screw.

Lift off shutter speed dial.

Remove the collar beneath the dial.

Installation Notes: Make sure that the tab on the shutter speed resistor mates properly with this slot on the shutter speed dial.

Place a tool in the fork of the rewind shaft. Turn the rewind knob counterclockwise to loosen it.

Remove the lock ring underneath the rewind knob.

Remove the cover plate.

Remove two M1.7 x 3.2 mm screws.

Remove two M1.7 x 2 mm countersunk screws.

Lift off top cover.

The release cable pin in the shutter button is loose and may fall out.

Apply isopropyl alcohol to soften the leatherette adhesive.

Turn the self-timer lever to the charged position.

Peel the leatherette off the camera body, carefully working it over the self-timer lever.

Remove one loose cover panel.

Repeat for the opposite panel.

Unsolder two yellow wires for the aperture resistor.

Remove four M1.9 x 3.9 mm screws.

Lift off front board.

Look for shim washers at the screw locations and note their positions.

Remove two M1.7 x 4.3 mm screws.

Lift off the aperture resistor.

Remove two bushings.

Remove two M1.7 x 2.9 mm screws.

Carefully lift off the aperture coupling ring. It is still attached by a long coil spring.

Detach the coil spring from the front board.