For those of you who the 3 switches (cooling source) on the aforementioned fridge.
The gas switch on mine was not holding.
Having taken the fridge out and the switch block, the switches are held in a holder by a metal surround. Prying the prongs releases the switches. The switches are held by a spring loaded plastic plate. Pressing another switch to deactivate moves plastic shims to deswitch the active switch.
So having taken my unit apart i found the culprit.
The plastic plate had snapped at the end. See Picture. I popped on some epoxy, but after a couple of uses it broke again. It snapped at the weakest point. I thought about a plastic weld. But its far too thin there.
So after a few thoughts off too a 3D printer - easy peasy they said so I am having one made, I asked them to make the snapped edge 1mm thicker - clearly the weakspot - then again its a good 36 years old.
If anyone is having same issues let me know and I can more made up and offer them for sale.