I thought crap- blown head gasket today. No over heating, no excess or any steam from exhaust, no coolant in oil dip stick but should I be concerned bout build up of dark brown scale on rad cap? Slight milk under oil cap and sump looks clear still. A15 did it too. Would it be just condensation build up from catch can again?
Just wondering if it's just scale from sitting or crap from the block. It's not head gasket sludge like I've seen.

I haven't driven it for 2 weeks. Just took for a drive and felt fine and no overheating etc. Still no steam from exhaust. There was some vapor from oil catch can, so left car running and took of oil cap. Big waft of vapour and no slight milk on oil cap.

Figure it's just condensation so incentive to drive more but concerned bout scaling.

Spoke with piggy, he reckons get an exhaust gas analyzer on rad to check if it's exhaust gas in coolant.

Any ideas or thoughts in it.

yes that is normal.

Replacing the coolant every 2 years with fresh coolant mix helps keep it clean. Running it for 2 weeks on regular water will be fairly dirty.

It's running coolant. I mean I havent driven it fir 2 weeks

Pretty normal Mik. Most cars will produce a certain amount of scale. You'd only be worried if it was a really oily sludge and your coolant level had dropped noticably.
Quite likely the scale is from years gone by. The engine may have been run for an extended period of time with no coolant/rust inhibitor which casued a build up in the coolant passages that is slowly releasing itself into the coolant. There will also always be a bit of condensation under your oil cap.

Engine was stored dry for a dew years so that's probably what you mean not run and dry for a few years