Sometimes it's quick and easy.
This beautiful, heavy and absolutely high-quality zoom from the USA with an MD connection is also a joy for the eye:
The aperture lever did not release the closed aperture and the aperture blades were a bit oily.
This could be fixed at the desk in less than half an hour:
The bayonet screws came loose without resistance, as did two screws from the collar of the rear lens unit.
The third screw remained tight and resisted.
But this time it wasn't a game stopper, because after loosening three small screws on the tube above the aperture ring - and lifting it slightly - the aperture lever worked again as intended.
I didn't want to get to the bottom of it any further. I was grateful for the quick fix, screwed it back in and turned my attention to the aperture blades.
Just as you would like, the rear lens unit could be loosened with the spanner wrench and unscrewed on the lens with the lens sucker:
Zippo lighter fluid was applied several times, the aperture blades were moved, the fuel/oil was dabbed off and then dried with warm air:
Everything went smoothly - that happens too
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