10 micron versus 2 micron fuel filters

[FF]

With a very high flowing engine like a Detroit the 2 does fine , as in a few hours all the fuel has been filtered a couple of times.

So on the second day of a cruise the only gropsh comes from the dock fuel pump and a Baja will catch most of that , before it gets in the tank.

The docks that complain most about the slow fill frequently have the worst fuel.

The 30 to 10 , or 10 to 2 seems like the only virtue is both filters will get used not just one.

That increases the surface area , and the cost is less as both should have PM before any plugging.

 

[Keith]

Who started this again? Oh, Wxx3... that's OK, it's always a fun time. Now let's get to guns on board too.

 

[Capthead]

A Barrett 50 cal on my boat.

 

[mark2020]

Not even close...

Read Steve D'Antonio's article in Passagemaker...
Fuel Filter Micron Ratings Explained | PassageMaker

"Now, back to your mechanic’s comments. Technically, he’s right in that this is Yanmar’s advice, however, I don’t necessarily agree with Yanmar’s reasoning as to why they recommend 10 or 30 micron primary filter elements"

Steve D does believe in multi-stage but there's NO complete or even reasonable agreement as to why...and plenty of boaters running all 2 micron can verify that on low fuel burn engines...there's NO reasonable difference in maintenance and performance.

Here's from Yanmar help

FUEL HELP

"Spring when it's still cold, the 'summer' diesel will block 2 micron filters, causing the engine to slow or even stop. My experience with this was on high horsepower engines fitted with 2 micron primary fuel filters only. Fitting 10 micron filters solved the problem."

If you read it it says "high hp engines" and switching from 2 micron...yet nothing about how a 2 micron may not be suitable for all year round use or on lower hp engines.

Cummins doesn't even state what is "preferred micron rating" just that THEIR filters are OK...

": What is the difference between Absolute and Nominal micron rating?
A: Micron rating is the size of particles which are filtered out by filters at a certain efficiency. When this efficiency is at least 98.6%, we speak about absolute micron rating/filtration. Nominal micron rating is just a commercial trick for all efficiencies lower than 98.6%, meaning that for the same micron rating (for ex. 10 µ) in the case of nominal rating, not all particles will be captured in the filter as in the case of absolute micron rating. "

Frequently Asked Questions

yet here's another clip from Cummins

"Remember: 3 micron on-engine, stage 2 filters, should never be pre-filled."

Cummins Engines

So the guy from Alaska Diesel probably misquoted Steve D, can't change a RACOR in less than 5 minutes, thinks everyone has hot engine rooms full of diesel...and doesn't REALLY know what some of the BIG diesel engine manufature's recommend or really care about.

Sounds to me like a guy who has himself convinced he's right and his way is the only way....

That's the best answer I've ever seen.
I once asked a similar question and the answer was the same as what you said.

 

[FF]

"Remember: 3 micron on-engine, stage 2 filters, should never be pre-filled."

This caution is for folks that do not have filtered fuel to fill a canister with and filters that are not gravity filled..

The usual fill solution is ATF , which is clean , cheap, and easy to store.