what would turn p.o.e. oil to a yellow color?
20+ yr old low temp rack system 502 with m.o. converted to hp62 (404a) p.o.e oil appox 4 yrs ago. The oil was changed one year ago with new liqiud driers rcw-48 and new
oil filter/drier of-303. Installed new oil filter today and noticed the yellow oil, never seen it before,tried acid test,(just to make sure) it passed, any ideas?