I have a gallon of carburetor cleaner (paint type can w/ dipping
basket) that I've had for a couple of years.  It's stored in my heated
garage, and was sealed shut last time I used it.  There is no evidence
of evaporation (in other words, the can is still full).

When I went to use it today, the surface was littered with little
blobs of something - looked like moisture or maybe oil?  Really looks
like oil floating on water - would oil float on carb. cleaner?  The
only carb. I've soaked in there was off a small 2 stroke outboard
engine, so the oil could have come from that.

Also, when I kind of stirred the fluid with the strainer basket, some
very fine stuff started floating around, something that is in
suspension, but towards the bottom of the can.  It is not obvious
contamination of particles because that would sink to the bottom and
sit there.  This stuff is very fine and floats around with minimal
movement of the basket.

Is this stuff contamination, or is it something normal that just has
to be mixed up before use?

If it is contamination, can I filter this stuff so I can use it?  How
would you recommend filtering it?

The surface blobs - what do you think they are?  How to remove it?

Thanks much!