Brian Louis Barnes has written a detailed step by step strip and rebuild of PD46 carbs which is stored in the files section of this website. At first it seems a bit daunting and complicated but if you're methodical and follow what he says you'll get an understanding of the carbs and realise that actually there isn't that much to it. Take lots of pictures, and especially of the spring between 2 & 3 that works the chokes on 3 & 4 so you know how it goes back when you rebuild them. I've just had to strip mine and at the same time I've helicoiled all the screwholes for the float bowls. Another slightly nervy task which with care has ended up a complete success.
