Brass cylinders average running temperature

[Preseli Chris]

Hi All .
Question . Approximately what is the average temperature one can expect the brass cylinders on a live steam loco to reach in degrees Celsius , factoring the blow off valve operating at 40psi and varying engine loads.

I have sourced some engine block paint and some etch primer which can handle up to 200c . By painting the cylinders will this affect the heat dispersion adversely or am I being to critical

Chris

[Old Man Aaron]

You're all good, painted or not. Boiling point of water at 100psi is around 160C, so any engine paint will do you just fine.
I've never had any problems with etch primer at the relatively low temperatures of our little kettles.