Coolant loss/rough running.

[GEARJAMMER]

Evening all.

I started my Monaro today and moved it across the yard, I got out and left it ticking over, I then got distracted which resulted in the car ticking over for about an hour. When i returned to it it was running rough and the cooling fans were roaring away a good'un, the dash was displaying 'Engine temperature high' and 'Check engine'.
I moved the car and the engine settled down back to normal and then drove up and down the industrial estate and all seemed well untill I stopped and it started running rough again.
Closer inspection under the bonnet shows coolant all around the bottom of the radiator area, mainly the drivers side.
How do I tell wether I've got a bust radiator or pipe somewhere? I'm assuming fill the rad back up with water and start it up and see if its coming from anywhere obvious. This leads me onto the next question.... Where do you put the water? There's the rad cap which is hidden under the plastic cowling attached to the slam panel which seems a bit of a ball ache just to fill with water or there is the yellow cap on the right Jan side that indicates coolant level, can the water go in there?
I've not been able to investigate much more than that at the moment given the weather and its dark, will investigate further tomorrow when I got some light on the subject but any tips/advice would be gladly received.

Cheers.

[GEARJAMMER]

I'm hoping/assuming the rough running was just down to the engine getting hot due to the loss of coolant?

[snowwolf]

Hope when you look in daylight it is all ok and was just an expansion leakage, the running rough bit could be just leads breaking down and the steam has found the arc leakage points