Oil in the Spark 2005 cooling tube

Greetings, when I went to take refrigerant I found that inside the bottle where it is thrown, there is a yellowish and oily viscosity. I would like to know what can mean. Before I have been told that I must change the crankshaft retain because I have a small oil leak and then I wonder if one has to do with the other. What should I do?

On occasions they get to do (small) of the antifreeze and it has nothing to do with the retaining of the follow that does not run any cooling vein now the antifreeze is something oily and orange pink green or blue if in your deposit there are coffee or black substance then if there is oil in your antifreeze. luck