MSR Windburner repair and cleaning
Recently one of our Instructors experienced problems with his excellent MSR Windburner. The water boiled very slowly - 10 minutes per liter instead of 5. At first, he sinned on the quality of the gas (refilled cylinders were used). But I have had a similar burner working quietly for a year on refilled cylinders with “automotive” gas, and I had to give up this hypothesis. To understand the problem, we decided to examine and clean both burners. And this is where difficulties arose...
Firstly, we suddenly realized that MSR gas burners, unlike multifuel ones, do not come with any keys. Even in abundant conditions at home, finding suitable tools took a lot of time, and even on a hike it would be quite a quest.
The "nozzle + pipeline" block was removed relatively easily - it was necessary to unscrew only one large nut. But unscrewing the nozzle from the pipeline was not possible the first time. I held the line head with pliers and tried to turn the injector with a large adjustable wrench. However, even with great leverage, it was not easy. In the field, working with a non-existent universal wrench and a multitool, you can get completely stuck at this stage.
The injector still gave in! By the way, there was a funny “crystalline” soot on its outer surface, which I managed to scrape off with a screwdriver without any problems. This soot did not block the outlet and therefore this cleaning did not affect the operation of the burner in any way.
But the most interesting thing was on the back (inner) side of the nozzle. My burner had a tiny plastic screw sticking out of the gas supply hole of the nozzle without a head. It blocked at least half the cross-section of the gas duct and gas penetrated out only thanks to cuts on the screw and loose threads.
What is this thing? It might be some kind of fuse. Have you heard the story about the burner-killing fuses in the MSR Reactor? The same situation is possible here too.
This hypothesis is supported by the fact that on the second, “instructor” MSR Windburner burner, this plastic screw was slightly melted. Yes! This is the reason for the poor performance of that Windburner!
Using a thin watch screwdriver, we managed to pry out the melted screw from the nozzle. The burner was assembled and it worked like new. The story seemed to end with a happy ending, but there is something alarming about this situation:
- There are no instructions on the MSR website for cleaning the Windburner.
- There are no parts (not even jets) for sale for the Windburner. And the nozzles from the Expedition Service Kit (for multi-fuel burners) do not fit there, I checked.
I really like this burner, but it would be even better if the manufacturer had a little less secrets from its customers.
Kirill Yasko, October 3, 2019