Coolant leak, UV dye checking

[james250]

My IS250 has some sort of coolant leak for sure as the overflow bottle levels drop even after topping up. It's not a major leak that I can see. My water pump and thermostat were changed few years ago. I cannot see any pink crust anywhere visible. There is no mayonnaise like substance in oil. The only place I see what may seem like crusty pink coolant residue is right along the bottom seam of the radiator. But cannot be sure. Ive seen some UV dye kits on eBay that covers upto 10L of coolant. My question is, is coolant dye safe for our super long life pink coolant? I probably will end up having to drain most of it anyway if I find the leak to change any components

[steve2006]

Personally I wouldn’t put anything foreign in my coolant, particularly so from an eBay seller.

Given the radiator is showing signs and the age I would be considering a replacement is due, with very small seepage even a pressure test is unlikely to show the exact spot.

[james250]

I am suspecting the radiator as I can feel it's a bit wet under the radiator by the drain plug area. Maybe the plastic housing has a crack somewhere. Like you said with the age maybe worth just replacing radiator for now. After car has been running for a while I do get a sweet smell of coolant at the front of the engine bay area. Do you know if the bumper needs removing to change the radiator?

Also, with a small leak I'm assuming coolant system will not pressurize and hence could potentially overheat?