I bought some fluorescent oil dye that is used with a light to help find oil leaks. Was wondering if anyone has used something like this and if so, did you have better success when the oil was dirty or fresh after a change? Also does it make a difference if its easier to see in the daytime or at night? Thanks

 

I used it once in a motor and did it with dirty oil on a gasser. What I did was clean everything really well under the hood and underneath, let it dry. Dumped the dye in, let it run for a while to let it leak oil back out, and searched with a black light which lit the dye right up. It was daytime when I did it inside and had no issues finding where it came from

 

I have used it in air conditioning on vehicles and really had not much luck, visually seeing the refer oil or using an electronic Freon detector works way better. Engine oil use is definitely different though.