Typically Diesel as it leaves the refineries is virtually the same. The taxes vary on the road vs marine use diesel. For many years, road deiesl had greater taxes and so marine diesel was cheaper. In recent years that has changed. Diesel was dyed to distigusih marine from road diesel to demonstrate that the proper taxes were paid on the
fuel in your tank.
Various outlets put biocides and conditioners in marine diesel
fuels since it is recognized that marine diesel typically sits in the user''s tanks longer than road diesel.
Over the years I have gotten more water out of
fuels purchased at gas stations than from
fuel docks. I do try to
fuel up a facilities likely to have a greater turn over in its
fuel supply but I am not sure that I am not just being superstitious.
If I have concerns about the
fuel that I am filling I first
pump a gallon or two into milk jugs and let it sit a moment. Water and silt will separate out pretty quickly. The
fuel should be translucent to lightly tinted. If in doubt you pour off a little from the top of the milk jug into a glass jar and look for debris. Anything you can''t see should be picked up by your filters.
Beyond the above, it is important to have primary and secondary filters, If you depend heavily on motoring, you should have a spare parallel filter/water separator that you can easily switch over to on the fly. I have a little
rig that lets me reach the lowest point in my
fuel tank and
pump out any water or debris and I
pump out enough
fuel every time I do an oil change to determine the condition of the
fuel in the tank.
Good luck
Jeff