Patio door won't fully deadlock

Hi,

I've fitted a new Yale door master gearbox and locking system for my french doors. However, once complete I realised that that I could not fully deadlock the system. The hooks etc pop out as they should, and I can do everything apart from that last little turn of the key to deadlock the door, even when forcefully pulling the handle up.

I wondered if it was the cylinder, so I just fit another one Euro-star one today. However, it has not fixed the problem.

It is not an alignment issue as I have the same problem with the door open.

So, even with a brand new gearbox, system, and cylinder, no joy! Am i missing something really simple that I need to do when first fitting the cylinder?! Could it be an issue with the door handles themselves? I doubt it as they look fine and turn the door OK .

Am well and truly out of ideas!

If you have separate shootbolts connected to the mechanism top and bottom it's very likely then that you have connected them to the main mechanism 1 tooth out of place, essentially the shootbolt is reaching it's full extent of travel before the main gearbox and handles are right up, if the key won't click over even with the door open then the handle isn't right up, that's the likely issue, disconnect one shootbolt at a time and try, my betting is it's the bottom one

crank93: legend, that sorted it!

I had looked at loads of YouTube videos, forums etc and you were the first I saw to mention the teeth placement. Really appreciate your quick reply and helpm as I would never have worked that out myself

Glad you got it sorted, bookmark this site, always comes in handy