Nice Toona manual release no longer works

[McP_Farringdon]

Hi, I have an old TOONA series 5 (TO5024) and the manual release no longer works on one ram. 

I can open the release handle and it levers down the release pin but not far enough. I could see everything is at least moving inside when I opened the arm up - nothing is seized. The manual release doesn't work because the motor remains engaged. It appears the release pin (a little vertical rod which gets pushed down by the release handle) doesn't push the clutch away from the worm drive far enough. Looks like it needs ~2mm more vertical movement on the release pin. Is there an adjustment mechanism somewhere? There is also a spring inside the clutch (worm wheel assembly) although you can't actually see that - is that something that gets worn? It still feels springy. Any tips would be great.

I have now removed the release handle and also tried replacing the brass coloured release pin (you can see the domed tip of it in my pic attached) with a long bolt which I then pushed down hard as far as it would go. Even with presumably significantly more vertical movement on this release pin, the clutch is not releasing. Anyone else had this trouble and know a solution? I suspect it may be quite common. I'll open the whole thing up later this week and check the internal mechanism but I can drive the motor forwards and backwards with a 12V supply no problem.

[McP_Farringdon]

Issue resolved.

I eventually  noticed that the metal plate (long front bracket in Nice parts description) which links the wooden gate to the motorised arm was seized on to the 'nut with fork' so it couldn't rotate at the motorised arm end. After removing the holding bolt and applying plenty of WD40 it became loose and I worked it so it could rotate reasonably freely again. After reassembly onto the gate the manual release worked.  Yay ! It really requires the mechanical advantage of being attached to the gate to check as its difficult to apply enough force to the long front bracket + 'nut with fork' assembly on a work bench.

I am taking the Nice parts description from an exploded diagram https://electricgatespares.com/nice-toon...-c765.html