swifty
Well-Known Member
I have the usual set up of diesel Filters, Racor 500 and then screw on filter VP part no.21492771. My question is what filter should be in the Racor 500, 10 or 30 microns.
This has come up before and you will not get a consistent answer. I fit 10micron in the primary filter because filers are not perfect and the specification usually sayes something like "10 micron at 90% efficiency" so having two fine filters in series should result in much higher efficiency than having a 30 followed by a 10. I've not found a disadvantage in this method in the last 30 years.I have the usual set up of diesel Filters, Racor 500 and then screw on filter VP part no.21492771. My question is what filter should be in the Racor 500, 10 or 30 microns.