Fuel Filter Micron level?

LMBoat

LMBoat

Well-Known Member
Oct 4, 2006
753
Ft Lauderdale
Boat Info
1999 450 EB
Engines
Cummins 6CTA's
We just got a new to us '99 450 EB with Cummins 6CTA's. I'm getting everthing "ship shape". The spare fuel filters that were on the boat are 30 micron. I can't find any reference as to what micro level to use. Is 30 correct? 20? 10? 5? Same question for the Westerbeke 10.0 BTD.
 
Hi Larry, assuming the engines are 1999 vintage, you are just fine using Racor filters at 30 Microns, and your on engines "Last Chance" filter as per Cummins spec.

The more you reduce the micron level the more vacuum you need to maintain proper fuel flow. The mechanical 6CTA engine doesn't require the same filtration levels as the later iterations of this engine with common rail system. When swapping out that Fleet Guard FF, be sure to fill it with fresh diesel before spinning it on. Those later models do not want the FF pre filled, yours should be.

Use the Racor Red top Filters 30 Microns and you'll be happy.

On your Westerbeke, same answer, 30 mics is fine, but do check that dinky on engine filter and if packed with stuff, change it. I look at mine every 100 hours of so and before I fill the tanks. I buy these Westerbeke filters 6 at a time.

Chad
 
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I replaced mine with 30 micron elements, 900MA 2040PMOR.

Congrats on the purchase, LArry. Welcome to the Cummins club.
 
Thanks Guys. We waited a while to find the right boat with the right engines. These are orginal to the boat. 780 hours. They have run well thus far. I'm looking foward to having them, although that Strb seawater pump is a bear. I've changed the impellers, zinces, trans fluild. Oil & fuel filters were just changed before we got the boat, but will be doing that shorty. Thanks for the help.

And if you know of anyone looking for a very well kept 330, please let me know. I'll be more excited about the new boat when I'm not a 2 boat owner!
 
LMBoat said:
.... although that Strb seawater pump is a bear. ...
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Isn't the port the one with very limited access? At least it's that way on all DBs I've been on. The stbd pump is facing the accees openning between the engines. I found that it's very easy to work on, but the port one was another story.
 
fwebster said:
He's working on an EB Alex, not a DB...................
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Yeah, I noticed that, Frank. But, I was thinking that the engines were positioned in the same direction as in DB. If they're, then logically it's the same issue as in DB.

......I just found one pic of EB engine room and it looks like the engines are turned the other way around. That explains the difference. My bad.
 
LMBoat said:
Thanks Guys. We waited a while to find the right boat with the right engines. These are orginal to the boat. 780 hours. They have run well thus far. I'm looking foward to having them, although that Strb seawater pump is a bear. I've changed the impellers, zinces, trans fluild. Oil & fuel filters were just changed before we got the boat, but will be doing that shorty. Thanks for the help.

And if you know of anyone looking for a very well kept 330, please let me know. I'll be more excited about the new boat when I'm not a 2 boat owner!
Click to expand...

Hi Larry, I can't help in getting a buyer, BUT I'm a willing help on your 6CTA's. I've been hugging mine for some 7 years now and have well earned lessons. Also, where to buy parts, what mech's to use, fuel distributors. Private message me and we can hook up sometime.:smt024

Chad
 
Per my Jedi Master "FW" I'm on overkill with my Racors being @ 2 Micron because my CATs' engine mounted filter is 2 micron and so I really should be @ 10 microns in my Racors, but my diesel mechanic said use 2 micron and so I'm doing what he said..... Being in the PNW I do not have the bad growth issues as some of you in warmer climates suffer from.
 
With Caterpillar engines, if you are using Cat OEM high Efficiency filters, your secondary filters are already 2 micron. Using 2 microns on the Racor primary filters will catch particles in the fuel, but it also makes the secondary filter redundant and useless. The more practical approach is to use 30 micron filters on the primaries and Cat High Efficiency 2 micron filters on the engine mounted secondaries. The 30 micron elements trap the majority of what is in the fuel and will only pass those particles smaller than 30 microns. The 2 micron secondary filters prevent anything large enough to damage the pump or injectors from getting through the system. The fuel system is designed to use larger particle trap size filters on the primary filters and the smallest trap size on the secondary filter. Using the same 2 micron filter on the Racor and secondary does not improve your fuel quality and does nothing more for you than increase your maintenance cost.

Changing filters at every second refuel is like going rabbit hunting with a Howitzer..............I change my filters once a year and have run as much as 250 hours on them, and they are never dirty.
 
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I also practice the FW 30/2 micron filtration regiment. I installed a set of vacuum guages on my Racors to let me know when they are getting dirty. Having only a single baby 500MA filter on each main, doesn't allow me the luxury of waiting for failure. With dual racors, you at least have a fighting chance of switching sides in a bad situation to get the motor back online.

Typically, I change the secondary filters annually and the primaries twice a season. I don't necessarily need to the change out the primaries twice, but I figure it's good practice and adds a level of security.
 
However, Dom brings up a good point.

His boat came with a single 500MA Racor that flows 60 GPH. My boat was ordered with larger dual 900MA Racors that flow 180 GPH and our engines are essentially the same. With 30 micron elements, he has very little, if any, excess capacity should he gets a clogged filter. If he were using 2 micron Racors he would have even less excess capacity.
 
Now I'm relatively new to the boat (only 4 years) and have only had to due a mid season change one time. Other then that, it's once a year or approx. every 100 hours. Your results may vary......:huh:
 
osd9 said:
I also practice the FW 30/2 micron filtration regiment. I installed a set of vacuum guages on my Racors to let me know when they are getting dirty. Having only a single baby 500MA filter on each main, doesn't allow me the luxury of waiting for failure. With dual racors, you at least have a fighting chance of switching sides in a bad situation to get the motor back online.

Typically, I change the secondary filters annually and the primaries twice a season. I don't necessarily need to the change out the primaries twice, but I figure it's good practice and adds a level of security.
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Frank, don't you recommend having both racors inline vs. one in a dual set-up? Less chance for restricting fuel flow, while still maintaining ability to detect filter problems via rpm changes, vac gages and such?
 
Yes......I think both should be open and functioning. The capacity is there, so with both on-line it would take a real bad load of fuel to keep you from getting to safe water in case you needed to change filters. While it can be done, changing filters or even screwing with the valve on the Racors can be a significant challenge when you have no head-way and are bouncing around in 4-5 ft seas while crawling across hot engines.
 
I don't have dual Racors on my 410DA. I have, however, given serious consideration to upgrading my fuel filtration system. My preferred option would be to install a set of dual 900MA Racors. My second option is to double up on my existing 500MAs.

However, because the total max fuel flow requirement for each of my motors, including the return, is less than one 500MA filter specs.....and way less than one 900MA filter specs.......I don't see any advantage to having them both online at the same time. In fact, I would think that running them both online at the same time defeats the advantage that having redundant filters does offer.

If, for example, I should get a bad load of fuel, and clog a filter, by keeping one filter in standby, I would still have that standby filter available to 'instantly' switch to so that I could continue on to either safer waters or maybe even my final destination with minimal inconvenience.
 
But, your one filter on line would clog twice as fast. The fuel supply system on Sea Rays is air tight so if you do get a clog with both filters online, the added flow rate with both filters just causes the engine affected to slow down, at first a few rpms, then, as it gets worse, a few hundred rpm's, but you still have an hour or more at cruise speeds. Pull it back to 10-12 kts off plane and the fuel requirement drops to 5-7 gph and the added flow rate will let you limp along for hours and hours. With a single 500MA, if you get a clog, your flow drops drastically and you are at idle immediately, assuming you catch it before the engine ingests air.

The difference of one vs. both is a small issue, but the thing I would try to avoid at all costs is running one of these engines out of fuel. Restricting the available flow because you want "stand by filtration" certainly increases the chances of an engine sucking air. ANd, I can't think of a worse job than purging the air out of a diesel while you are stuck in a sea way bouncing around in 4-5 ft swells with a hot, mad wife and a bunch of family asking how much longer?"
 
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