Potential fuel filter issue

[Lars Larsen]

I’m in the process of modifying the filters on my boat, to a 2 stage system, per the “filtration the Seaboard way” article in Tony’s Tips. I’ve mentioned it to a couple of knowledgeable diesel guys, and they caution against it, due to the possible restriction of flow feeding the injector pump. My boat has 2) 6BTA 5.9 M3 engines with mechanical injector pumps (factory reman in 2007, with about 900 hours on them). The boat does not have a lift pump, so it will be siphoning fuel directly through the filters. I currently have 1 Racor filter for each engine. A Cummins mechanic told me that the smallest filter I should use in this setup is a 30 micron, so as not to starve the pump, which seems useless for decent filtration. I have a Fleetguard FS19596 and a FS1218 that I want to put in series, in place of the Racor’s. Can you tell me if this is an issue, and if so, is there a work around to use the 2 stage filtration? I have a 300 gallon tank with the tank bottom about 2 feet below the injector pumps on the engines, so at half full, fuel level would be about 1 foot below injector pump.

Topic

[Rob Schepis]

Lars, you did yourself right by knowing what you were being fed was suspect and then coming here. Trust me, there would be A LOT of unhappy boaters (recreational and commercial) out there if the SMX DD setup did not perform as advertised.. Keep us informed as to your progress, maybe some pics too, and any others info or guidance you might need along the way..

[Lars Larsen]

Thanks for the replies! One of the “knowledgeable” guys was the same mechanic that serviced the boat for the previous owner. He never serviced the aftercoolers or transmission coolers, which I found were about ready to destroy the engines if not taken care of, so that’s why I thought I’d ask the experts. I design hydraulic systems for a living, and I preach filtration to all of my customers. It was one of the first things on my to-do list for upgrades on the boat. Not being a seasoned diesel mechanic, I thought it best to ask, before causing more issues.

Thanks again for the info

[Tony Athens]

No offense, but your knowledge-able diesel guys are clueless.. So much bad info out there. It all come down to?measured restriction, not a seat of the pants opinion, or typical dock talk.. .

As to the actual filters–Use the FS1000 instead of the FS 19516 ( kinda pricey and not needed for your engine as it has a WIF sensor on it) .. Use 1/2″ lines to and from the filters

As to sending fuel to the engine–You should always send fuel “ready to use” to the engine regardless of the on-engine fuel filter, BTW which is under pressure, not suction– Just think about it…………………. That’s why I call it “last chance”– I certainly do like not be to be that situation, especially on a boat at sea.

Tony

[Rob Schepis]

Further to donald’s post here is an article specific to restriction

https://www.sbmar.com/articles/understanding-fuel-line-sizes-vs-fuel-supply-restriction/

[donald roth]

“The boat does not have a lift pump”
No, but the engine does, and it is quite strong and reliable.
Go re-read Tony’s articles on fuel filtration and move ahead from there.
You are not siphoning anything when the tank level is below the pump/filters.
I Recommend the squeeze bulb primer and vacuum gauge with your setup.
I have used Tony’s filtration setup for several years now, not one fuel related problem, and no more Racor nightmares!

[Author]

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