Beginners help with a Medeco Biaxial 51S

[AcesN8s]

Hey everyone, this is my first post on these forums so if Im posting in the wrong spot or break a rule (I did read the rules so hoepfully that ownt happen) forgive me.

Anyway, I've been picking for about 6 months now and I've gotten to where picking my locks with different security pin set ups doesnt remain a challenge for very long so I decided to move into higher security locks and bought a lot off do ebay that contained a Medeco Biaxial (silver mortise lock with "Medeco" written across the top, two half circles under it to the left and 51S over UL to the right)

Since I bought it used with no key I decided to take it apart and make sure everything was in working order before I pinned it up with progressively harder setups. I thought that if I just undid the screws on top of the cylinder and removed all of the pins and the tail piece that there wouldnt be anything to block the sidebar so the cylinder would rotate and I could remove and inspect it.

But once I removed all the pin stacks and the screw on tail piece the cylinder still will just barely rotate or pull straight forward about 1/4 inch. Did I skip a step or is there something wrong with my lock?

I should probably say that it was pretty dirty when it came, not so much that i wouldnt expect it to function, but could it be that the sidebar is too gummed up to retract? if so then what can I do to fix it?

Any help is greatly appreciated, sorry if this is a dumb question but I used the search function and didnt see anyone else ask this and I'm fresh out of ideas..

[femurat]

Hello and welcome to the forum.

Taking apart a mortise or rim cylinder that has the set screws on top of pin chambers should be quite simple.
Are you sure you removed all the pins? Sometimes a long key pin gets stuck and doesn't come out when you flip the cylinder upside down. Then it prevents the plug from rotating or coming out.

Can you post a picture of the back of lock? Just to be sure you removed everything from the back too. But even if you didn't, the plug without pins should rotate.

Cheers

[AcesN8s]

Thank you for the reply, and for validating that these locks work like i thought they did. Here are the pictures showing everything I have removed. The last pic shows how far the core will pull straight out. It absolutely will not rotate, Im bending my .05 pry bar almost permanently and theres no give.

Anyone have any ideas?

[AcesN8s]

At this point Im thinking that the sidebar must be blocked or frozen somehow, but Ive never heard about this happening before. Does anyone have any experience with this or any possible solutions?

[stratmando]

I was thinking sidebar may be stuck as well, I would Try Blaster or other penetrating oil, push plug back and forth in cylinder even if only a little, maybe smack down on a piece of wood to free side bar, and even any pins that might have been missed? Good luck