Kiev 4 Shutter problem

Good evening! I just recently came into possession of a Kiev 4 with a sluggish shutter. Upon arrival the first thing I checked was the shutter, and found it quite sluggish. Although the timing was roughly correct at shutter speeds of 1/2 through 1/10 (based on a very unscientific test using my iPhone's slo-mo video mode and counting frames), it quickly became obvious that the shutter speeds topped out at around 1/125 (with 1/125 ACTUALLY measuring 1/60).

Knowing I really had nothing to lose, as I am not going to request a refund from the eBay seller in Ukraine, I set out to tear it down and see if I could figure out the problem.

The first thing that I noticed was that the first shutter curtain does not seem to fall even when the latch is released (https://imgur.com/a/h4GUSxu). My understanding is that the latch releases the lower curtain and then the gearing dictates when the second curtain falls. Is this correct?

Here is a video of the shutter in B mode: https://imgur.com/a/SvYbsKS

I am currently at the point where, if I disassemble any further, I may not be able to reassemble it correctly. I'm hoping someone could give me some pointers on where to go from here. I feel like it might have something to do with the ribbons, but I'm not sure. The ribbons seem to be in good condition, but do appear to be oily. Could this oil be causing excess friction, enough to slow down the shutter?

Any advice is appreciated!

I think I can see the problem - there appears to be loads of black oil or grease on the escapement gears and winding mechanism? All these gears need cleaning with lighter fuel (naptha), you really need to get the shutter crate out of the body to do this. You can buy litre bottles of Naptha from camping stores - in the UK its branded as Coleman Fuel. You will need to be very careful not to get the stuff all over the blinds and shutter cords - best solution is to use a small paint brush to flood it through the mechanism with the that part facing downwards into a small container. it needs to be shiny-clean to run properly with just a spot of thin oil on the pivots/axles (please not WD40!! this gums things up again.) Don't be tempted to remove the shutter blinds as its a nightmare to retime the shutter if you are not familiar with the process.
******PLEASE MAKE SURE THE AXLE DOES NOT FALL OUT OF THE TOP SHUTTER SPINDLE! It will be loose if you remove the shutter crate from the body *****

Thank you for the suggestion SteveA. I think the "black grease" you are seeing is just a byproduct of the light from my iPhone. However, I took your advice anyway and flushed the gears with naphtha (in my case, Zippo lighter fuel as that's what I had on hand). No dice -- the shutter is still very sluggish. I'm starting to wonder if the shutter drum(s) is/are shot? There does not seem to be a way to adjust the drum tension on this Kiev (a 1978 model according to the serial) the way there is on the original Contax shutter.

I fear I have purchased an expensive shelf piece; I knew this would be a gamble from the very start though, purchasing a Soviet camera on eBay from a seller in Ukraine. However, if I can't get it working, at least I've done some small thing to aid at least one Ukranian.

Hi, the shutter tension adjustment should still be the same - the bottom right hand side of the lower drum, the little slotted washer that has to be moved aside then the adjusting screw. If the shutter opens and closes smartly on B then the tension is probably OK. Its possible that someone has had a go at the camera and messed up the timing - the slow speeds escapement may not be disengaging. You can tell this if you get the buzzing sound on speeds faster than 1/50 second.
If you wind and set the shutter on 1/1250 second, there should be about 6 to 7 teeth of the big gear visible before the cutout section of it. More or less than this and the speeds will be adrift. There should be 1.5 to 2 of the strips of the upper blind visible below the top of the shutter crate. If you have a copy of Maizenburgs book its all in there, have attached image for reference

Cheers,

Steve
http://www.ussrphoto.com/UserContent2/1882022_kiev.jpg

Thank you sir, your advice is much appreciated. I literally JUST discovered the Maizenburg book this morning and will have another go at the shutter mechanism this evening after work. Thanks!