Ralph, Rob, Steve(?). Thank You all!

Stew. Thanks! Re- Mrs. Drillin......... As long as we keep on buying Warburtons sliced, she'll never know!

So.........
Yesterday, I fired up, at the start of a full heat test run. Away she went, running nicely, as usual.

Time to fill the cooling system. Using a 5% mix of Shell Supercut-Plus, instead of the previous Bluecol top up mix.......

A couple of minutes later, the well remembered
water boiling sounds started. And she stopped.

This proves, once again. Stirling Principle engines will
not run on steam!

Removing the thumbscrew, and extracting the stainless steel air tube, revealed smears of coolant.
The fluid must be leaking up the outside, and into the power cylinder.

I machined 3off, 5thou deep recesses, into the tube's o/d. To hold the Hylomar, and seal between air tube and brass tube's bore.
Then I fired up the burner several times, spinning the engine to allow it to breath, and dry out.
Left the system open, and this morning all was well, and dry.

Generous application of Hylomar sealed it, as hoped.
Set up, in the kitchen. Not a particularly good idea, so I was informed.......

But all went well, during a half hour run.......

Observations.
The burner system is too on/ off. Also, needs a smaller diameter, more concentrated flame.
Smoke from under the feet, indicated things were getting much too hot. Couldn't touch the underside of the base wood!

The copper chimney got a bit warm, too.......

I'm going to try this choke ring, next. Failing that, it's a new rose, with a smaller drilled area.......

Must look for a No 3 jet......
David D