I hate predictive text - 'fort' should be 'dirt' and 'fixed' should be 'fixes' . Hope that's clear.Thanks harbourseal, I'll let you know how I get on. I've already tried the fixed you suggested, and the plunger is moving ok, so the fort must be inside the switch. I'll have a go tomorrow at removing it and let you know how things go.
PaulWhen they Renault 4 was first produced they used a brass thread which usually will undo with your fingers the plastic thread is more resistant and a pain some other Renaults of the. Had the switch in a more friendly location found you one on eBay if you're still looking
https://rover.ebay.com/rover/0/0/0?mpre=https://www.ebay.co.uk/ulk/itm/332214850592