Hi, folks,
Like all Rubies, mine has a burner that it far too vigorous for the boiler it's in.
Even at low regulator settings, the burner puts out way too much flame,
resulting in lots of flame in the smokebox, smokebox temps that will give you
2nd-degree burns, and a lot of wasted heat. This weekend I installed the no.
3 gas jet from Sulphur Springs in my Ruby. Here's a report on the procedure
and results.
It took me a while to get to it because the burner in my engine (no. 87) was
bored a little too small, so I had to turn down the outside diameter of the jet
holder a little. I chucked it in the lathe and turned off a couple of thousandths
of an inch and it slipped right in. Bob Paule tells me that the burners he's
measured had a bore of 8mm, which makes more sense than the
measurement I took from mine.
Once installed, the burner wouldn't stay lit unless I turned up the regulator a
lot, in which case the flame billowed out the smokebox front but wouldn't light
in the flue. I eventually traced the problem to the jet and its holder. There was
gas leaking around the threads, and not much going through the burner.
Some PTFE tape fixed that, and the engine steamed splendidly thereafter.
I didn't have the chance yet to do timings to see how long it would run on one
tank and what the water consumption per tank is. With the old jet, I got about
15 minutes of running time, using 50ml of water. I'm hoping to get both longer
runs and use more of the water in the boiler (both benefits reported by others
who have made this change).
-vance-
