Technical Uv dye

I have a leak in my old gmc truck coolant so i used the uv dye and was scared when i saw the engine oil glowed yellow. I did an experiment and put the uv light in a new oil container. Same yellow color. What is in oil to get it to glow?

 

What kind of leak and what kind of dye did you use?

 

Coolant overflow tank dropping. Yellow uv coolant dye from autozone.

 

Why not just pressure test the cooling system and look for the leak?

 

Maybe it's scared. Never seen a Ford do that.

 

Loads of ingredients in oil. No surprise if a few show up in UV.

 

I tested it in the dark while hot and pressurized. Nothing. I bought a pressure
Testing kit on amazon.

 

Pressure testing a cooling system for leaks is better done with a cold engine. When the engine warms up, parts expand and leaks tend to seal up.

 

Did it lose pressure?

 

These fine gents are offering advice and help. I'm wondering if the dye that glows showed the radiator leak, not just the oil?

 

Typically there is nothing in oil that will make oil fluoresce under UV light. Any oil related UV dye that I have seen typically turns the oil a greenish color as well. I would be asking if you have a head gasket or other leak that is causing the oil and coolant to mix?