What micron fuel filters do you use?

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We believe in stopping contaminants as far from the engine as possible. For us, that's the Racors that are first in line after the tanks. The next filters are the two on each engine. After them, it's the injection pumps.

So on the advice of our diesel shop and people we know in the marine propulsion and generator manufacturing industry, it's 2 microns all around.

Another very good point has been made here that has actually never occurred to me. And that is the ease of changing the filter elements in the Racors. An added plus for us is that in our fuel system, which uses only gravity to move fuel from the saddle and day tanks to each engine''s lift pump, changing a filter element in the Racors does not require bleeding the fuel system. Changing the spin-on filters on the engines does.
 
Having the 2 micron first means you will be starving the engine and changing a filter faster than you need to. The majority of contaminants are larger than 30 microns. Again there is a reason almost all engine manufacturers recommend progressive filtration. And since we are also weighing in with "that's what some guy told me", I would add all the very experienced mechanics (that would be three) I have used say go with a progressive set up. I would encourage reading the articles I posted as well as Calder.

So here is an anecdote. On my Detroits, the specified sequence is a 30 primary, followed by a 10 or 7 secondary on engine, followed by 2 micron screens on the injectors. I asked one of my mechanics who had worked on DDs for 25 years, if the screens needed cleaning or replacement on some scheduled basis. He said he had never seen a dirty one that needed any action taken. Now plenty of engines, due to design spec a smaller secondary, and will put the 2 micron as the "last chance" filter.
 
caltexflanc said:
Having the 2 micron first means you will be starving the engine and changing a filter faster than you need to..
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If you routinely take on crappy fuel, or you have lots of crud in the bottom of your tanks that can get stirred up, or you have fuel on the boat that's been there for a few years, or you've got a water and bug problem in your tanks, sure, I absolutely agree with the progressive filter theory.

But none of those things apply to our boat. In the 17-1/2 years we've had our boat, I have yet to see any water in the bottom of the Racor bowls (and our tanks drain from their lowest points--- when a tank is empty it is empty), nor have I ever seen any crud buildup in the Racor filter elements when I change them.

While there may be exceptions, the fuel sold in the PNW seems in our experience to be of high quality. This is certainly the case in our harbor, where the single fuel supplier is where the 2,000 recreational boats in our marina along with the USCG fuel up, so they go through their storage tanks very quickly.

And even if we had crud for our filters to catch, I would much rather be changing out a filter that's farther away from the injection pump more often than be hoping that the filters immediately in front of the injection pumps were catching all the crap that was passing through the upstream filters. Particularly when the upstream Racor elements are so easy and fast to change.
 
Switching first-line fuel filters can be as simple as throwing a switch.





Wouldn't look forward replacing a filter underway (the heat, the motion, ugh, can think of the nausea and uncomfort.)
 
Marin said:
Fine. So here's some more distraction for you. We use 2 micron filters on everything fuel-related. If our anchor used a fuel filter, we'd use a 2 micron on it, too.
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What do you mean if?:facepalm:

I use a 2 mic on mine:socool:
 
2 micron is what came on/with my boat - for gensets and main. We shook up the tanks in a big way on Chatham sound and after 120 hours the needle on the vacuum gauge hasn't moved off zero. Maybe it's broken?

My Bruce doesn't need a filter - it does that job by itself as it drags through the mud.

Richard
 
Wxx3 said:
What do you mean if?:facepalm:

I use a 2 mic on mine:socool:
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Oh, crap, really? I've missed that entirely. And here I thought I was really familiar with our anchor.

We have some Baldwin spin-ons on the boat as spares. I'll keep my fingers crossed that when we go up to the boat this weekend one of them will fit the anchor.

Thanks for the heads up on this.
 
markpierce said:
Switching first-line fuel filters can be as simple as throwing a switch.





Wouldn't look forward replacing a filter underway (the heat, the motion, ugh, can think of the nausea and uncomfort.)
Click to expand...

Yep, that's my Racor 500 setup. It takes 30 seconds to turn the handle and only two minutes to change the filter, if need be.

And I'm sure many can do it faster than that...

Marin's advice makes too much sense to ignore.

Yes, Diesel manufacturers make all sorts of recommendations. Im sure a few are not even based on marketing, but I'm not even sure about that.

Most Product Managers will ell you the truth if you get them aside, everyone else is just reading from the brochure or lawyers statement.

Let me run a little scenario by you:

Engineers of the wonderful, big diesel maker, go running to the product manager, their new baby hot off the lathe, a gleam in their eyes.

PM they say, look at what we have made now. We know that if we recommend 2 mic filters everywhere, this engine could last forever.

Now, the PM DOES want the engine to last forever. He doesn't believe in planned obsolescence. Companies make money from increasing market share, not selling a lot of crap, that forces the consumer to look elsewhere.

But he asks the engineer, who is still drooling over his latest creation, "so with 2 micron filters everywhere, how often will the engine starve for fuel if the filters are not changed as needed?

Oh, Engineer says, we already thought of that. Smiling he shows the PM the data, with 2 mic filters and a user who does not pay attention, (Assuming 10% of all users are negligent), it is an expensive engine after all, this engine will die even for those negligent owners only 10% of the time, versus 5% is they use progressive filters.

ANd the PM asks, how will this affect the longetvity of the engine??

The engneer, still beaming, pulla out another sheet of paper. This data shows that under the best conditons, the engine will last 30,000 + hours and Probably avegage 20,000+ hours and even with the worst users, using cheap 10 micron filters made in China that are actually anywhere from 1 mcron to 50 microns and more random then the best computer program could produce.

Even these worst case owners this beauty will last 10-15,000 hours.

The PM pats the Engineer on the back, "Joe, you've designed a wonderful motor that will have our customers singing our praises int he after life.

There will probably be 10,000 (this number I don't know) of these motors under warranty at any given time. As everyone realises how great that is, those numbers will increase, BUT we will double our service calls just by telling folks to use the more restrictive filter.

The progressive filters will still do the job, but we will have far less calls and trips to start engines that would have kept running had they used progressive filters. So, even though the engine will last slightly less time, once we go about 20k hours, no one will notice, or remember whether that final number is 25k or 35k hours.,

But they will remember that that we had more service calls, even though their engine would have lasted a bit longer.

So let's just go with the progressive recommendation and make everyone happy.:dance::dance:​

Did I eve mention I was a Product Manager?

Not for a manufacturer, but the best companies make sure that the PMs and the Engineers are talking almost every day.

I have also mentioned too many times, this will be the last time, that I, in my early naive days, put 300 gallons of fuel in the new Dauntless, in tanks that taken 10 years to burn only 200 gallons.

1200 miles and 230 hours later,much of it off shore, the engine finally stopped due to clogged filters. Who knows what i was waiting for.:facepalm: I had arrived in NY a week earlier.:eek:

The switched the Racor and the engine started up 30 seconds.

2 mics for me.
 
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Wxx3 said:
Yep, that's my Racor 500 setup. It takes 30 seconds to turn the handle and only two minutes to change the filter, if need be. ...
Click to expand...

Moving the lever is instantaneous. But replacing the filter; those round rubber things for assuring a good seal slow me down drastically. Give me at least ten minutes!
 
Folks with screw on filters , on the engine or as a choice for filtration may wish to carry cans of ATF.

Diesel to fill filters is sometimes hard to obtain for filter filling with most boats diesel fuel setups.

The ATF will run the engine just fine with no harm to the fuel system or fuel.

For an offshore boat a gravity setup is best , but hard to re engineer if the boat builder had no idea.
 
FlyWright said:
I agree that the mfr/dealers know best. I got my info from the local Perkins dealer, Brian at British Marine. On my 4.236, I was advised to use 2 micron on the dual primaries and also on the engine mounted secondary.
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I would not equate what a manufacturer says with what their dealer(s) says. From the manufacturer I'd be looking for a written application guide, installation manual, or operators manual.

In my experience you are as likely to get a myth or wives' tale for a dealer as you are a repetition of the manufacturer's guidance.
 
roguewave said:
Thanks David, do you have an engine mounted fuel filter also? Mine has a R24T (24 bucks ea) on the engine and 2010's ($7.59) on the remote racor.
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I have a 1989 6BT and use NAPA 3358 fuel filters 10 Micron, $13.49. Our Racor is a 900 with 30 Micron and vac gauge. My first filter change was made after 4 years and 600 hours of use. The racor was clean. During that period I ran in rough conditions plently of times to stir up the tanks.
 
Marin said:
If you routinely take on crappy fuel, or you have lots of crud in the bottom of your tanks that can get stirred up, or you have fuel on the boat that's been there for a few years, or you've got a water and bug problem in your tanks, sure, I absolutely agree with the progressive filter theory.

But none of those things apply to our boat. In the 17-1/2 years we've had our boat, I have yet to see any water in the bottom of the Racor bowls (and our tanks drain from their lowest points--- when a tank is empty it is empty), nor have I ever seen any crud buildup in the Racor filter elements when I change them.

While there may be exceptions, the fuel sold in the PNW seems in our experience to be of high quality. This is certainly the case in our harbor, where the single fuel supplier is where the 2,000 recreational boats in our marina along with the USCG fuel up, so they go through their storage tanks very quickly.
Click to expand...

My experience on the Chesapeake Bay has been similar. I currently have a Cummins QSC common rail engine. I use a 10 micron Racor primary and a 2 micron on-engine Fleetguard filter. Cummins specifically recommends against filling the on-engine filter. Even the slightest amount of crud or grit can ruin an injector on a common rail engine. I carry a gallon of diesel to prime the Racor and the on-engine filter is self priming.
 
Something an industry friend sent me a couple of years ago.



Micron ratings can be fairly complex. It is imperative to know the efficiency (Beta Ratio) associated with the given micron rating. When a company publishes a micron rating without this information, it does not tell the customer how efficient the filter is at the given particle size. For instance, if Company X rates a filter at 15 micron, they may be referencing a nominal micron rating which could mean the filter is anywhere between 50% and 90% efficient at that particle size. Please see the links below for more information about the micron ratings of filters.

http://www.baldwinfilter.com/literature/english/10%20TSB's/89-5R3.pdf
http://www.baldwinfilter.com/literature/english/10%20TSB's/04-2R1.pdf
 
CPseudonym said:
In addition to Tom's excellent informational links here is one more.

http://pdf.cat.com/cda/files/3375312/7/Diesel+Fuel+Diesel+Fuel+Systems+LEBW4976-04.pdf

The replacement value of the CAT power generation equipment I'm responsible for is higher than the average boat on this forum. As such the CAT factory book IS the bible.
Click to expand...


Thanks Craig, great read. When it comes down to industrial dollars, cents and warranties maintaining clean fuel requires a "book" to go by.
 
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Fuel filtration can get opinionated. But as a general principal its a good idea to lead with a high capacity filter first in line followed by finer filtration closer to the engine. New common rail engines need tighter filtration as last resort. I and many others use multi stepped filtration in the form of three units. Two before the engine mounted filter which is speced to factory recommendations. Vacuum gauges with captured second needle on the filters is an other good refinement. The first filter is meant to stop water and large particles the second filter say 10 mics meant to further clean things up and the engine mounted 5 mics if CR or 10 mics if older iron to be a safe sure.
 
Probably best to use the OEM recommended by brand, not micron rating, on engine filter. Not all 2u or 5u filters are made the same nor have the same crud removal capability. If not done so, read TomBs post above in this regard.
 
For the record I had a 2 micron filter in my Racor in the past. But since it was the only filter (other than the little one on the engine) I decided I was inviting a plug up w such a fine mesh filter so I went to 10 microns. Still at 10 for the same reasons. Thirty microns would probably be fine but since the only fuel contamination problem I had was w pieces of thread sealant that crippled the fuel pump I don't think 10 micron filtration is too small. So 10 it is for me.
 
I go with a 10 micron primary and 2 micron secondary on the engine. I was using 2 micron on both but read that it's not the best thing for the fuel pump. Also yearly change of filters because the filter paper can start to dissolve and should be changed periodically. Maybe hype from Racor to sell more filters but not worth the risk when it comes to injectors and fuel injection pumps.
 
I put fuel in one tank from the pump and then I manually transfer / polish with a pump and 900 racor with 2 micron to a day tank , 20 or 30 gallons Then 10 micron before engine and 2 micron at engine . This was the original set up from PO . Not sure how good this is but seems to work . The transfer is kind of a PITA and sort of a rig . I just hook my leads from my polish pump to the generator battery .
 
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