Old Shipmate model. Burners HAD worked fine for many years but now the flame is quite weak. Kettle takes much longer to boil. Have lots of propane. I'm thinking that it could be the regulator is clogged. Somewhere I read that propane over time has a waxy substance left. Anyone have ideas and if I should clean the reg, is that a difficult job? Cruising right now through the Gulf Islands in BC so trying to buy a new reg would be tough.