G'Day,
 
After some help on magically appearing coolant around head on my X-Flow. Only happens after car has had a decent drive and then sat for a week or two. 
 
First time it happened was after I'd just fitted the motor so I doubled checked thermostat bolts, radiator hose etc and assumed a minute leak.
This time I know when I parked it up engine bay was clean and there is no signs of leakage from anywhere and on closer inspection no physical way for coolant to have leaked to where it is without evidence.
 
So now I think I must have an issue, could it be a porous head?
Has anyone had an issue like this before?
 
Pics attached....
 
 
 

Seems a bit of a strange spot for coolant to be- have you checked that the threads for the spark plug sockets are ok. Has the head had any work done to it- porting etc? Len

More likely that's from a small hole in the top rad hose or thermostat gasket.