Yamaha PSR-630 key repair

I am trying to repair my Yamaha PSR-630 keyboard, which has several dead keys. From vigorous online searching, it seems that the culprit is dust and I just need to remove the keys and clean the circuitry beneath. I am there, but I just cannot figure out how to disassemble/un-nest the white and black keys. There seem to be as many mechanisms for unlocking as there are key sets. These appear to be Style 59U keys, from what I’ve seen online. I have looked and looked but cannot figure out how to decouple. Does anyone have any insight on this?

Did you remove the keybed from the chassis? There may be other screws on the bottom you need to remove.

They are mounted in sets 4 whites on the bottom, then 3 whites interleaved on top and then the blacks on top of that - remove them as a set by lifting at the rear and you end up with this:

… which comes apart like this, but you don’t need to do so, just re-insert as a set.

Takes a bit of fiddling at first - once you done one you get the gist of it.
The need to fit into the hook of the weight lever all at once.

Thanks so much for the reply! I have been trying and trying to lift, but that is the part I can’t figure out. There is nowhere to grab it, and I’ve tried to gently pry it out with a number of items and it seems like I will just break the plastic. Do you have any more specific insight into how I lift from the rear?

You need to remove the keyframe from the unit (don’t know/see if you have done that) - you can’t remove the keys with the frame installed in the unit.

I always remove all of them - it is easier that way - may seem a bit more work but helps in the long run. Remove from left -to-right - put finger underneath the back of the first set - lift up then shift forwards and out …

I make a video later on but have to dis-assemble a unit I have on repair first …

It helps to know that I should proceed from left to right, as I was working the other direction. However, I’m still having problems getting the key frame out/finding anywhere I can put my finger beneath to lift up and out. I made a video to illustrate my problems but can’t seem to upload it here. I can send via email if you are interested. my email is cretintraditions@gmail.com

I am sorry to pester, and I remain great appreciative of the insights you’ve provided. But do let me know if you have any additional advice based on my follow-up comment the other day, or if you are able to make that video or look at the one I made.

thanks again.

While you have it apart replace the keyswitch circuit boards and the rubber contacts

I just removed and replaced these in my psr-630 and each bank of keys is interlocked with the prior bank by one (lego style notch). I believe the order is important, but also remove the blacks first, left to right, then the next white section left to right etc.