Kiev 60 shutter not closing help

Hello

I got a very good price on a full kiev 60 setup. Camera is in very good condition.

I'm trying to get to the bottom of an issue with a shutter curtain opening when cocked.

As the mirror locks down and shutter is set the first curtain returns to the left side of the camera (looking at the front) leaving the shutter open. When the shutter button is pressed the second shitter travels back and what sounds roughly like the correct speed.

I can't see anything visually wrong with the shutter mech, I've tried using a bit of lighter fluid to clean any old grease but it is really clean already. I know these cameras have issues with curtain tension could it be something with that?

Any help or advice would be appreciated.
Having trouble attaching photos at the moment but here are two videos of. The problem.



Apologise for the dodgy video hard to film and cock the camera at the same time.

I haven't done a deep dive into K60, but if anything like Praktisix where shutter / mirror box / film transport can be unbolted and lifted free from an outer "exoskeleton", it would give you much better access to the camera's inner workings. Shutter drums and rollers can be cleaned and lubed with the aid of a light oil diluted in solvent and applied with a syringe but avoid getting oil on the ribbons or rubberized fabric. Mirror box also likely needs attention. Supposedly, original factory lubricants were high-spec stuff, but they weren't aging well in the 1990s, let alone three decades hence.

Although it may be very tempting to fiddle with the shutter tension adjustments ("just a little bit more..."), I'd leave those alone for now, and concentrate on reducing friction.