That doesn't look much more than a bicycle chain - with a split link just before the rear cylinder exhaust cam sprocket.
Yep, scary to think of the damage it would do to the riders leg if it snaps. Although despite being a big capacity that engine is going to have very low compression and rev very slowly by todays standards, so it won’t be under the strain we’d imagine from a modern perspective. However, if I was running it as a vintage ride these days I’d want a guard on it and would probably wear a cricket box whilst riding.
Replies from me Dad: Picking up water from the troughs at too fast a speed - suspect it is just a demo. Windows probably closed in the first 2 coaches. The engine (without cladding) looks like at the end of a long rebuild and is having a boiler test. The steam is from the cylinder cocks. They are turned on initially allowing steam straight through to warm up the cylinder. If cold there is water condensation and not being compressible can cause piston/cylinder damage.
Is it sad that I find that fascinating and a great bit of info? Many thanks to your father. It's so obvious that a build up of Condensation could cause Hydraulic lock in the cylinder, but you'd not think of it until it was pointed out.
Yeah, stuff like that is always interesting. The old man is a bit of a steam railway buff and used to volunteer at the West Somerset Railway before it all got too political. He's lent me a "How Steam Locomotives Really Work" book which is, as you would imagine, as dry as a dry thing and I haven't yet got beyond page 12... ho hum. He has assured me I will be surprised at the technical abilities of the 19th century engineers - if I get that far
AFAIK the Flying Scotsman was being moved along tne maim line behind a diesel, they left the cylinder lubricators on as they should but they left the cylinder drain cocks closed. The cylinder oil built up and smashed the cylinder covers off Whoops.
I wonder when that was. The FS has had a really checkered history since decommissioning from public service, and a couple of previously very wealthy owners that it's bankrupted in short order. That incident could have been done on purpose so it couldn't make an engagement the owner couldn't afford to get it to. I'd imagine knocking up a couple of Cylinder covers and repairs, done by enthusiasts who's time is cheap, could be many times cheaper than a couple of days line rental and public liability insurance from British Rail.
