I guess your chassis is galvanised and then painted. If so, there is no serious problem.
My working life included making galvanised steel components so I have a bit of knowledge. Paint doesnt stick that well to zinc or any other non ferrous, not helped by the EU ban on etching primers, so bubbling paint coat isnt the best but its not surprising if MMC havent taken steps to paint it properly. But why paint it at all when galvanised? Presumably it happened when the undersealed the rest of the car.
Do not use a wire brush on it or sand it or indeed scrape with a sharp metal instrument. All of those might damage the galv. If it concerns you then spray it with black waxoyl. Personally I would probably just leave it alone. Difficult to tell from one photo.
No point in using rust preventers on galv. As for the springs, then the best idea is to remove the coils, blast and properly paint and prime. Leaf springs need dissembling to paint but again why not waxoyl.
Howard, Thankyou, that's great to hear. I posted another picture, which looks a bit worse, if you have anything to add, I would be very grateful
Stuart
