Hi, Brian: As you know, I'm reticent to put forth an opposing point of view, but here goes: Racor recommends 30 or 10 micron primaries with a 500-hour change interval; Lugger recommends changing the secondary at 600 hours. Based on experience, I believe that's conservative, and so I go about twice that. Of course, I buy fuel from trusted sources. Last October, I changed the 30-micron Racor primaries and the Lugger (Wix) 2-micron on-engine filter. Now, 813 meter hours and 2195 gallons of fuel later, I am still on the same filters, and have yet to switch the primary over. The gauge on the Racors reads the same as it did last fall. Regards, John "Seahorse" >> In normal operation the secondary is receiving fuel that has already been filtered down to 2 micron so it will have great life. Now I would love to here opposing points of view.

We have been using 2 micron Racor filters for six years on Ancora, and both Volvos keep running well. Of course, we change out every 100 hours. Ralph Salerno M/V ANCORA San Diego