LPG switch stopped working - major job?

[agence]

Hello,
I'm still talking about this old W123 converted to LPG, well I'm meant to be buying it this weekend but the electric switch which allows you to go between LPG and petrol via a button on the dash has ceased to work:
the owner assures me that it is easy to fit another one, and he has the part. Does anyone know if this is true? You can still switch between the 2 fuels manually under the bonnet but obviously that's not too handy.
We're meant to be having a go at it tomorrow
Thanks again for your help
Alex

 

[citroennut]

lpg

hi alex, the car should switch automatically between fuels and the only time you should need to switch manually is if you run out of gas and the empty alert sounds and you switch it off. must admit i try not to run on petrol if i can help it! wouldn't have thought it a big problem to fit new switch, though why was it broken and what system is the car running?
simon

 

[OlafMaxwell]

I did have one car converted to gas. The switch is linked to some other connections, petrol supply etc. I don't believe it is difficult to replace.

 

[turnipsock]

If the owner says it is easy to fit...why hasn't he fitted it?

The LPG car I had, you didn't have to use the switch at all. When the gas ran out, it would switch over to the expensive stuff automatically.

It may be a wiring problem rather than the switch, you never know.

Have you got the car?