oil

If it's new you might be loosing some oil past the rings (assuming an oiled piston compressor), till it runs in?

Or it could be the residue of any protective oil from the inside of the tank? <shrug>

Or it might be broken and you are trying to run a big single cylinder, one-shot diesel? ;-)

Cheers, T i m

You do get oil"carryover" on air compressors. Has to be removed if you intend to spray paint. There are "oil free" compressors that have diaphragms instead of pistons As the compressor runs in, the situation may improve as the piston rings bed in.

So you might want to eliminate or add oil to your compressed air depending on what you use it for.

There are also water eliminators.

thanks both ...