Pressurized Alcohol Stove Problem

[ve3qft]

My Princess alcohol/electric stove works very well and I like it.The main problem people seem to have with these is in performing an adequate preheat using a carefully controlled amount of alcohol. When the preheat is done properly, the stove lights easily and produces a nice flame for cooking.

My problem is that recently, first one burner, and now both burners, after running well for a while, turn red hot and the visible flame goes out. Clearly, there is still combustion: the element/head remains red hot until I turn off the liquid. Once I have let it cool for a moment, the burner relights perfectly, but then gradually does the same thing.

There is no variation in pressure during this time. The stove holds pressure perfectly and has no leaks.

It seems like this might be a fuel/air mixture problem; red hot combustion would seem to indicate too much air.

I have tried everything I can think of, with no change. Has anyone seen this behaviour?