Let's see if this fits and increases reliability.
I've cleaned and refitted the original. Though I think the issue may be with the burner. This seemed less well made. I have a new burner I can fit once the current mantle needs replacing. One of our other Scout leaders is getting a professionally serviced lantern so it will be interesting to compare light output.
The current arrangement needs the jet cleaning quite often to keep working well. Dirty fuel?

