What micron fuel filters do you use?

I'm flying out to work on and test the boat we bought. I'd like to bring filters with me so I don't have to buy them when I arrive. I have twin cummins 6BTA 5.9's that have a fuel filter on the engine as well as remote mounted racors. The engine filter is a 10 micron and I was wondering if the remote racor should be the same or should I go to the 30 micron.
Thanks

Most of the boats with Cummins 6BTAs around this area, including ours, use Racor 30 microns.

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.

Use what the engine manufacturer specifies. "How many microns" can easily turn into an anchor, one vs two, galley up / down. type thread.

caltexflanc said:

Use what the engine manufacturer specifies. "How many microns" can easily turn into an anchor, one vs two, galley up / down. type thread.

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Hey, I could use a little distraction from all the recent anchor discussion.

twistedtree said:

Hey, I could use a little distraction from all the recent anchor discussion.

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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.

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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That should stir the pot quite nicely.

I use 10's if fuel tanks are known clean, 30's if tanks are dirty.

I use 5738987655 micron filters for what it's worth. Also have a 46388373 on my Rocna.

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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Fleetguard FF5285 on engine. Confusing info as to whether this is a 10 or 20 micron.

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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Now THAT'S what I'm talking about

If my engine used more than 1.9 GPH...I might care....for now..2 micron all around....

I see no reason to go larger micron rating than the secondary filter. It makes the secondary's job easier and provides the needed level of filtration for the engine. My old mechanical Perkins 4.236 calls for 2U, so 2U it gets. For me, it's a no brainer. That's what mfr specs are for.

If your engine calls for 10U, use what the mfr recommends. Takes out the guesswork and doubt.

Here's a good explanation of why progressive filtration makes sense, and why virtually all engine mfrs. recommend it. Yes the guy is making a case for a product he sells, (and is duplicatable by other vendors and most standard primary/secondary set ups) but it helps explain why you don't want to put a primary filter the same rating as the secondary. By the way, he also explains in the second article why mere micron ratings are not always relevant when comparing one filter to another. Note the quote from the Lugger/Northernlights guy at the end.

Marine Fuel Filtration - “The Seaboard Way”

Fuel Filters

And if you want a more neutral party's opinion, consult Nigel Calder's discussion on fuel filters on page 370 of hs excellent"Boat Owner's Mechanical and Electrical Manual".

Using two-micron on the engine filters and the filters between engine and fuel tanks, but I've a small collection of ten-micron filters I'm tempted to use on the tanks-to-engine filters.

To my mind the question is where are the filters located , how easy is it to swap out the filters.

IF the filters are a bank with a switching lever , installed OUTSIDE the engine room where a filter change is easy , the 2 micron would be first choice.

Even the 2s will pass a percentage of bigger crap, so the 10s on the engine will still need changing , but not as often.

If the filters are buried in the engine room , the use of 30s and the 10 on the engine is usual , with a filter DP (differential pressure) gauge on the dash , you can at least know when to switch over , and change the plugged one.

Remember Otoole sez , "Murphy was an Optimist", so you may have to change filters underway, sometimes frequently.

With 30s first , the 10s will need more frequent changing..

roguewave said:

I'm flying out to work on and test the boat we bought. I'd like to bring filters with me so I don't have to buy them when I arrive. I have twin cummins 6BTA 5.9's that have a fuel filter on the engine as well as remote mounted racors. The engine filter is a 10 micron and I was wondering if the remote racor should be the same or should I go to the 30 micron.
Thanks

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Our 6CTA 8.3s want 30 micron elements in the primary filter/fuel-water separators (Racor, in our case), and 10 micron elements in the on-engine spin-on secondary. Latter is the Fleetguard product specified in the service manual for these engines.

-Chris

Same for me with the 2 micron all around

Glen

A few early morning thoughts on this anchor debate type subject --

In our lightly used vessels provided the fuel is reasonably clean to begin with, the "what micron filters to use" discussion seems best answered by "whatever." Once the engines start seeing many hundreds to thousands of hours per year, multi stage sequential fuel filtering is common (30u, 10u and on engine) often coupled with good high volume on board fuel polishing systems.

As often noted by FF and others the higher the volume the better when moving fuel around the tanks and through polishing filters. Once into larger vessels Alfa Laval type centrifugal filters are common. The old DD 2 strokes are wonderful in this regard as they move so much filtered fuel through their recirculation setup, not uncommon to hear of100 gph.

A few years ago a reasonably new Nordhavn 55 spent much of its time sitting at docks. With a combination of bad/wet "new" fuel and low turnover the entire fuel system became green. No amount of polishing or store bought additives would cure this issue so all tanks and systems were emptied and cleaned, thank goodness for sizable tank ports.

I'd venture a guess that most recreational boater fuel problems are from lack of turnover and once the bugs start growing in old fuel the list of issues skyrockets. So on vessels that only have about 50 to 150 hours per year on the engines, this could mean lightly used or maybe lightly abused.

Conflicting advice on how full to leave tanks each fall contributes to the issues. Leaving them full but with 3 or four years of fuel onboard can occur. Or leave them low with only a year or so onboard can lead to condensation say some. Oh what to do?

roguewave
I have same engines. Mine are mechanical injection. Cummins standard filter (on the engine) is 10 micron. I also use 10 micron as a prefilter. You will very soon pass all of your tank's volume through the filters with that engine. If you use 30 or 20 as a prefilter it will soon be doing nothing as the 10 on the engine will have treated everything in the tank.

Tony Athens of Seaboard Marine is one of the better experts on Cummins marine power, his website is chock full of information, I believe he preaches a stepped filter approach:
Custom Cummins Marine Diesel Repower Specialists | Seaboard Marine

For my Yanmars it is their recommendation to have a 30 micron primary and 10 micron secondary, but like others have said, many different opinions.

OK, I can't help myself....

I'm not sure if all do, but the engine manufacturers who I've looked at specify what should be used for the off-engine filter. So they specify both the primary (off-engine) and secondary (on-engine) filters. In all cases it's a stepped filtration of some sort. Why do you suppose that is? Do you think they know something that we don't?

By the way, raw water filtration for water makers is the same. They ALL use stepped filters starting with large micron size and working down to smaller. Maybe they know something about this as well, but I'm sure we all know better.

Well, this turned into a very informative thread. Thank you all for the education and input, it has been well received. Next week I'll be packin multiple different micron filters in my luggage to New Hampshire :lol:

caltexflanc said:

Here's a good explanation of why progressive filtration makes sense, and why virtually all engine mfrs. recommend it.

Marine Fuel Filtration - “The Seaboard Way”

Fuel Filters

.

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That's what I've done...A huge 27 micron Fleetguard, followed downstream by a 10 micron Racor and on engine filter.

Based on the fleetgaurd's performance I'm a believer.

See more here:

http://www.trawlerforum.com/forums/s32/funky-fuel-filters-19536.html

stone beach said:

roguewave
I have same engines. Mine are mechanical injection. Cummins standard filter (on the engine) is 10 micron. I also use 10 micron as a prefilter. You will very soon pass all of your tank's volume through the filters with that engine. If you use 30 or 20 as a prefilter it will soon be doing nothing as the 10 on the engine will have treated everything in the tank.

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Numerous tests done by the filter manufacturers over the years have shown that with diesel fuel, slowly over time decreases in the beta number or openings occur from say 30u to 20, 10 and finally totally plugged. This is why some of us have vacuum gauges, to know when filter change time has arrived.

I have hands on industrial experience with filters and screens finding the same thing. Quite simply, this is why we have protective filters and sizing devices of all sorts, to let them get plugged so the downstream operations won't suffer.

For boats, good information covering fuel filtration can be found, as previously suggested, on boatdiesel.

twistedtree said:

OK, I can't help myself....

I'm not sure if all do, but the engine manufacturers who I've looked at specify what should be used for the off-engine filter. So they specify both the primary (off-engine) and secondary (on-engine) filters. In all cases it's a stepped filtration of some sort. Why do you suppose that is? Do you think they know something that we don't?

By the way, raw water filtration for water makers is the same. They ALL use stepped filters starting with large micron size and working down to smaller. Maybe they know something about this as well, but I'm sure we all know better.

Click to expand...

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.

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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Al

Do your on engine filters have a stamp that says 2u? The dozens of factory issue Perkins Sabre/Cat filters I have bought are stated by factory literature to be 5 to7u but no stamp saying what the are, confusing for sure. Cross reference website is:


dieseldistributors.co.nz

sunchaser said:

Al

Do your on engine filters have a stamp that says 2u? The dozens of factory issue Perkins Sabre/Cat filters I have bought are stated by factory literature to be 5 to7u but no stamp saying what the are, confusing for sure.


dieseldistributors.co.nz

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No spec on the filter case as I recall, but they are Perkins brand secondary filters purchased from the Perkins dealer, British Marine, Oakland, CA.

Bay Pelican is 2 microns, genset, wing engine and both the primary and secondary on the main. Rather change the Racors than the filters on the engines.

Ok. lots of good thoughts here. But. if a filter clogs and stalls the engine, which one do you want to change in a seaway? For me the racor would be easier to change. So to me that is a good argument to use the same filter aperature on both filters.

But at the moment, I have a 30 mic at the racor and a 10 on the engine. (6bta as well). after I use up a couple of more on board filters, I'll buy some of the 10 mic filters and use them.