Not exactly kosher for fuel filtering before entering the high pressure pump.
The Racor filter (primary filter) has a coarse filter for removing the coarse particles while the small filter on the engine (secondary filter ) has a 10-15 micron filter to ensure that very little in the way of abrasive grit gets into the high pressure pump.
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I use a 10 micron filter in the Racor. This filter is massive for this little engine. It never gets even close to plugged. I also have a vacuum gauge on it for monitoring purposes.
If that 10 micron filter were to ever plug up with "coarse particles" then that means I've got some kind of serious problem with my tank, which would warrant a serious cleaning out rather than adding coarser filters into the system.
Frankly, in my experience I never really *need* to change it, but I will swap it out when I do my scheduled maintenance just to give me something to do.... The filters on the 500 are much cheaper than the ones on the smaller Racors and are super easy to change out, so what the heck? It's also kind of fun to do with my nifty priming system.
The tiny on-engine filter on the 1GM, on the other hand, is a real pain in the keester. The filter does not go in easily and it's simple to spill fuel when doing so. The filter housing is known for developing cracks at the bleed screw, which admits air into the system. And one time the tightening ring that holds the filter in place vibrated loose and spilled a bunch of diesel in my bilge! I'm glad to be rid of it. One less point of failure.