Guys,

So, I read that the new K&N HP3003 is the old 3002. I've also read that the only difference is that the old 3003 has a built-in bypass valve, and the old 3002 did not. Does this mean that the 3003 I've currently got, after ordering a 3002 (Amazon), does NOT have the bypass valve? How do I know if I have the if I have the NEW 3003 or the OLD 3003? And, with the stock Merc 496 configuration (oil temp sender mods aside), do I NEED a bypass valve, in addition to one that may or may not already be there? Is there one in the stock configuration?

Thanks. Brad.

The factory 496 gen 7s have a 30psi bypass valve located in the block. You don't need a bypass valve in the filter but either way would run fine.

60 microns equals: 0.0023",, since a regular 51060 or 61 flows MORE THEN A TYPICAL BBC PUMPS, theres NO absolutely reason to run the R series of filter on a recreational boat, heavier can, great, since no ones exploding "standard " wix filter cans thats ZERO benefit too.Unless your putting your throttle on dashboard with your oil at 70 degrees, which no one should be doing, the regular 60 and 61 filters Six to EIGHT TIMES better fwiw

If I have a choice to run a better fiter with a better micron rating why would I chose a Racing filter designed for flow on race cars? .. even if an engine went 100 passes without changing oil or filter (nobody thats smart would do that) thats 10 hrs. I certainly don`t change my oil every 10 hrs.
I`m running the filter with more filtration, to me that`s a no brainer.
I like my filters to filter .. never had a flow issue due to a filter being too good.

They say pictures speak a thousand words. As a side note, this HP 500 had 17 hours of offshore factory race time when I bought it. Never used a drop of oil which is crazy for a BB. You guys telling me I just got lucky my chit didn't blow up? I'm showing you empirical evidence. We don't run in a dirt track environment. 15W50 Mobil 1 changed every 50 hours.

So that brings up another question, oil weight to go along with a good filter, I just had the 502 Mag in my boat rebuilt its now a 509 with a hotter cam and 9.3:1 compression. Its a lake boat so high RPM runs for long periods of time do NOT happen, I ran Rotella 10w40 in it last season as a break in but is that to light of an oil? Do I need to run 15/50?

I always ran a straight 50W (Valvoline VR1) you dont really need the first number as its for cold weather (winter) running equivalent....

I'm a big believer in plenty of flow on a high performance marine engine don't get me wrong. that's why I run -12 lines, full flow bends, etc. I run the 2 quart super long oil filters so I can get way more flow than I'd need, while also getting filtration in the 20-30 micron range. Oil analysis particle count results show they are filtering out the particles in the size range they should. It's about surface area of the media, so get a filter with lots of pleats and as long as you can fit. There was a study done years ago on engine wear and it was found on a typical engine with average clearances, particles less than 20 microns didn't cause significant wear, they just passed through.