Originally Posted By: TiredTrucker
Originally Posted By: NHGUY
I say its lack of sulphur in todays diesel fuels.Without that lubricant,rubber seals will dry out/crack,shrink....etc I have seen,and smelt many a diesel that when new runs clean and with nary a fume,fast forward a couple years and they are smoking and smelling like diesels of old.While they may last 200-300K miles,most of those are dirty,smelly miles.
Sulfur was NOT the source of the lubricity in diesel. The process to remove sulfur removed the lubricity qualities of diesel. Biodiesel, which has virtually no sulfur, will add tremendous amounts of lubricity to diesel, and do so in small quantities. A simple B2 bio blend will take ULSD diesel lubricity to LSD levels. A B5-B10 blend will exceed lubricity of pre LSD levels, or better than the "old diesel" we had in the early 90's.
That's not entirely true....
Neat biodiesel has lubricity equal to ULSD, the added lubricity comes from impurities in biodiesel, namely mono-, di- and triglycerides. There are quite a few studies confirming this.
So as biodiesel production will become cleaner, the lubricity will drop again. You just can't be sure how lubricious your biodiesel blend is...
That said, just like motoroil it doesn't matter how the blend is made only the end result matters. B20 will likely have enough impurities in it to assure proper lubrication, this isn't always true for B5.