Lifespan of refurbished Austin 7 engine

[Andy Bennett]

On the subject of warming up - I have wondered whether the thermosiphon acts a bit like a thermostat. The water in the block is not going to move out of the block and into the radiator in significant quantities until the block has warmed up. It wouldn't be as positive as a thermostat, but may be facilitating a faster warm up than a pumped system with no thermostat or a failed thermostat.

Yes, that's a very interesting point; I'd never considered it.

Yes that is exactly what happens. A while back I took step by step thermal pictures of my engine heating up which shows this. I will try to dig them out of my picture archive and post here later.
Andy