Considering Reorganizing Fuel Filtration

[kapnd]

Traditional filtering systems are inadequate for today's fuels.
The diesel fuel you now burn is not the same stuff it was a few years ago, and is much more capable of carrying contaminants through your filtering system.
Changing and inconsistent regulations have even the filter manufacturers confused as to what's really required, and how it is rated.
Three or more stages of filtration (decreasing porosity) are vital to your fuel system's health and longevity.

 

[Heron]

Three or more stages of filtration (decreasing porosity) are vital to your fuel system's health and longevity.

That's what I've done....27 -> 10 -> 2 micron filtration..

 

[twistedtree]

Getting specific, you QSC engine requires 10 micro filtration before the engine. Not 30, 10. This is direct from the QSC installation manual. So whatever you do, you need to fix that. It's also why you are plugging up the on engine 2 micron, which as I'm sure you now know is a royal pain to change because it takes forever to bleed.

As for active/standby filters as you currently have, vs series filters (presumably 30 followed by 10), I'd personally stay with what you have. Being able to switch filters while underway is huge IMO. The real objective is to protect the 2 micron on engine filter so it only ever has to be changed at its scheduled interval. The dual Racors with 10 micron elements will accomplish that and make for quick and easy filter changes when/if necessary. We cruised over 10,000 miles on our QSC engines that way with no filer issues other than scheduled maintenance.

As for 2 micron in the Racors, that's a bad idea in this case. If they start to restrict you can get cavitation which can intern damage your high pressure pump. It's a common rail thing and perhaps less applicable to older engines, but applicable to yours. So just do what the manufacturer calls for and use 10. Gee, there seems to be an echo in this room

 

[caltexflanc]

Traditional filtering systems are inadequate for today's fuels.
The diesel fuel you now burn is not the same stuff it was a few years ago, and is much more capable of carrying contaminants through your filtering system.

I'd like to see some facts on that. My impression is just the opposite, but "impression" is the operative word there.

 

[Tom.B]

Back when we owned our old boat with a Perkins 6.354, I converted to a spin-on secondary filter. Back then, a great little store called Roy's Marine in Grantsboro, NC turned me onto Baldwin brand filters. I reached out to the company regarding an o-ring I lost and needed a replacement. I got a personal reply from Travis Windberg, Manager Of Service Engineering. Here is a snip of the email conversation we had:

Me >>> One quick question: Why isn't the micron filtration of your filters listed anywhere? Is there something I don't know about filtration that I should know? I have two Racor 500's with a 30m and 10m filter cartridges. I was hoping to have a 2m as the "secondary" CAV filter.

Travis >>> 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

This series of Racor numbers crosses to our PF598 series. The PF598 is five micron absolute. Therefore, its nominal rating would be at two micron or smaller. If you have further questions, please feel free to contact me.

I only used Baldwin filters after that (well, until Roy's closed). These older (non-common rail) motors don't need "double-super-duper-mega" filtering. IMHO, using what Racor calls a 2 micron for primary filtration (even secondary) is taking a bit of a risk. Both in pump strain and premature clogging. They do fine with a 30 primary and, in the most technical term from the catalogs... Secondary filter; whereas the micron rating is not even published. Heck, even my Volvos from 1999 only spec to 30 mic primary.

Certainly, I am no expert, but I learn by listening to experts and I think Travis qualifies.

 

[markpierce]

No doubt the filter volume and size need to correspond to the rate of fuel movement. A ten-gallon per hour capacity has different needs than one of a 100 gallons. Don't know how much my fuel pump moves to provide a maximum of four GPH (80 hp) verses that needed for a engines totaling 200 or more.

 

[O C Diver]

No doubt the filter volume and size need to correspond to the rate of fuel movement. A ten-gallon per hour capacity has different needs than one of a 100 gallons. Don't know how much my fuel pump moves to provide a maximum of four GPH (60 hp) verses that needed for a engines totaling 200 or more.

Lift pump on a JD 4045 at 2,400 RPM is 32 GPH or about a half a gallon per minute. Number varies with engine RPM. 1,800 RPM should be around 24 GPH.

Ted

 

[markpierce]

Lift pump on a JD 4045 at 2,400 RPM is 32 GPH or about a half a gallon per minute. Number varies with engine RPM. 1,800 RPM should be around 24 GPH.

Ted

Thanks!. At 1800 RPM (normal cruise speed and a knot less than hull-speed), the engine is consuming only about 1.7 gallons an hour. The fuel should be being polished at a high rate. With 79-gallon fuel tanks using one tank at a time, a tank is polished in about four hours if starting out full.

 

[Ski in NC]

Lift pump might be capable of 32gph, but that does not mean the return flow is anywhere near that. I don't know y'alls JD's very well, but that seems to be a lot of return flow for a smallish engine.

 

[O C Diver]

Lift pump might be capable of 32gph, but that does not mean the return flow is anywhere near that. I don't know y'alls JD's very well, but that seems to be a lot of return flow for a smallish engine.

Same pump is used on JD 6068 series up to 300 HP. Return line is 1/8" mpt. Don't know if you can push 1/2 gallon per minute through 1/8" pipe. Minimum fuel feed line is 1/4". I'm most likely returning 18 GPH at cruise.

Ted