Montblanc 146G piston sleeve loose

[mcannad1]

Hello,

I have a montblanc 146G in Green Celluloid with the Telescopic Piston. When the piston is extended the piston sleeve seems to come loose and disengage thus preventing the piston from being retracted. If the sleeve is held in place with while working the mechanism, the piston extends and retracts as it should. Does anyone have any idea how to potentially repair this so that the sleeve stays on track and allows the piston to be extended and retracted correctly?146 Piston.PNG