Hi, Thank you so much for your quck and helpful replies. A nice surprise! The Hipolito is a 500cp model not 400 ( I got confused by looking at spares and thought I'd got it wrong) and I don't think anyone has messed with the bits. It had been unused for a long time before I got it.
I think the cleaning would be a good idea and I will check for holes in the mantel. I remember a blueish bit on the glass that appeared soon after lighting it and perhaps a hole was responsible. I won't be visiting the lamp until the weekend as it lives in a 1930s railway goods wagon we are converting to a "living van" for visiting vintage rallies.
I also have a couple of old Tilley lamps which need attention and a Bialaddin which works well, so I hope your ethusiasm will inspire me to get them sorted out before the end of the summer.
Thanks again to you all for the tips, I will let you know how I get on.
Kind regards
Annie