A previous owner has replaced the radiator on my 1970 Series 2 FHC with an alloy one:-
You want to make sure the pressure cap is at the highest point in the cooling system.
I’ve always thought the S2 system design was a bit unusual, with that expansion tank on the firewall, but it seems to work fine. That ‘atypical’ configuration is probably what caused someone to switch them around…they were probably more used to the typical “recovery tank” configuration.
There’s nothing specific about aluminum radiators that would cause it to function differently, so I think I’d put them back to the original configuration if I were in your shoes.
The caps are reversed. There’s no reason why they would have to be swapped like this.
OK I will switch the caps. Thanks
