10 on the tanks and 2 on the engines.
Ok, but was that the boat builder or the engine manufacturer's recommendation? Next time you go by your JD marine dealer, ask the manufacturer's representative what they recommend and why.My "pre-engine" Racors came with 2-micron filters, and I haven't seen a need to change that tactic.
Not knowing how your entire fuel system is set up....the only answer that makes sense to me if you step back far enough is to agree that progressive filtration is the way to go. It's not what I have currently but will be changing based on what I have been reading and observing for years about fuel systems.30, 10, or 2 micron filter element in the primary Racor 500?
I've got a single Lister Petter 4cyl. 80hp in a Grand Banks 32.
10 on the tanks and 2 on the engines.
We use 2 micron filters for our JD engine.[/QUOTE
Does JD say they are 2 for the on engine filter bodies? On my non electronic engines nobody makes an on engine 2, they are 5 to 7 microns as deemed just fine by Cat and Perkins Sabre for the OEM injectors and injection pump.
10 on the tanks and 2 on the engines.
Yes, it marked clearly on the outside of the filter. 10 micron before the lift pump and 2 micron after the lift pump.We use 2 micron filters for our JD engine.[/QUOTE
Does JD say they are 2 for the on engine filter bodies? On my non electronic engines nobody makes an on engine 2, they are 5 to 7 microns as deemed just fine by Cat and Perkins Sabre for the OEM injectors and injection pump.
Ted
Your missing part of how filtration works. I'm not going to get the terms correct, but here is the principle. There is the filtration as you view it where the media is blocking / trapping particles down to a certain size. The second type I believe is called "caking". This is where the surface of the media has contaminants. Other contaminants stick to these. So, even though your element is rated at 30 microns, the filter pics up the majority of contaminants between 2 and 30 microns. Parker (Racor) has an excellent PDF on this explaining how it works. I just cant seem to find it on the internet.anyone with a Cummins should use the same size in the prefilter as the engine filter..."well thats a bold statement" I hear...or maybe it was a different retort with the same initials (bs) !!
why do I say this? because you are returning so much fuel back to the tank that pretty soon your prefilter will be doing nothing if it has a larger micron number than the engine filter, the engine filter size has already done the work.
if you have more than one filter before the engine then staging makes perfect sense.
the prefilter(s) are supposed to condition the fuel for use, they are often called conditioning filter(s), the engine filter is there to protect the engine from a fault in the conditioning system. following that understanding the final prefilter should be the same size as the engine filter.
So, even though your element is rated at 30 microns, the filter pics up the majority of contaminants between 2 and 30 microns. Parker (Racor) has an excellent PDF on this explaining how it works. Ted