Have now descaled the boiler, the sight glass works as it should and I checked it for leaks and it all appears to be fine. I decided to remove the cladding so that the boiler can be seen in its true glory, have given it a gentle clean by hand so as not to remove the boilers charm, I am pleased with the results, I did not want it to look like a brand new boiler. I have enjoyed owning and working on this boiler, however, another exciting project has just arrived so this boiler is going to have to make way to pay for the new and unexpected addition to the fleet. So if you know anyone thats refurbishing a 1920's /30's steam boat, this could be the ideal boiler for their project. Have kept the coal scuttle with the boiler since it has been used to fire the boiler by coal, however, the boiler is clearly intended to use a blow lamp style burner.