To FASS or not to FASS

[dave.higby]

A number of my fellow Selene owners have installed so-called “FASS” (trademark) fuel filtration systems to address a problem with lift pump failures on their single Cummins QSB 5.9 diesels. The FASS system has it’s own lift pump, with a particulate/water filter as well as an air separator. The popular configuration involves installing the FASS system upstream of the fuel distribution manifold and the primary fuel filters, which obviously pressurizes those components to something like 10 psi. I am wondering if anyone on this forum has experience with this system? A number of questions come to my tiny mind:
– Is it safe to pressurize the system upstream of the existing lift pump (the distribution manifold and the RACOR filters)? Parker says the RACORs are rated up to 15 psi. However, any leaks could generate a mist of atomized diesel fuel in the engine room which seems dangerous to me.
– If the existing lift pump does fail after the FASS system is installed, can the FASS system’s pump still push fuel through it to the high pressure injection pump?
– I use a vacuum guage on the RACORS to tell me when it’s time to change them. Seems like that wouldn’t work very well if the filters are under pressure?

I read somewhere else that an alternative (and cheaper/simpler) solution is to install a squeeze bulb downstream of the primary filters that would allow me to limp to port if the lift pump fails completely, provided I could find a volunteer to sit in the engine room and squeeze the bulb periodically. Is that really an option? Not the volunteer, that is. 🙂

Thanks in advance,

Dave

Topic

[dave.higby]

Thanks

Thanks for your reply Tony. I spoke to Brendan and Justin yesterday and they were extremely helpful. Based on advice from Brendan, I am going to go ahead and proactively replace my lift/priming pump since it is the original 2006 version. I am also looking hard at your double double quantum kit. I’m challenged for space in my engine room and am wondering if there is any point in retaining the existing dual Racor filters (in series with the quantum kit, that is). The Racors offer the advantage of being able to switch over to a clean filter on the fly if one plugs, but the filters on the quantum kit look easy and fast to replace, and with a good vacuum guage I should be able to tell well in advance when it’s time to change out the filters. So, I’m leaning toward taking the Racors out altogether. Your thoughts?

Also, are there any considerations with respect to how high the quantum unit should be mounted relative to fuel tanks and the lift/priming pump? I may have as much as 18″ to play with. Is lower better relative to the tanks?

[Mike Mason]

I have 2005 qsb’s with original pumps. 1400 hrs no issues.

[Tony Athens]

Dave,

I think have are over reacting to the potential failure of the electric lift pump on the QSB 5.9’s….Yes & yes, on early ones we probably saw a 10-15% failure rate but that was back in the 2004-2007 era designs.. And, I say that when they did fail, that engine still ran, they just could not make much over 1000-1200 RPM..If the tank were full, they ran better

The last 10 yrs or so–Maybe we sell a few pumps a year on engines that still have the earlier designed pumps. Next month, I am removing a pair of early QSB 5.9 that have over 30000 each hours on them…We replaced his early lift pumps over 25000 hours ago.. That’s it..

Yes, I know the FASS sysem. I scan the Dodge truck forums too.. Do I think it is applicable to the type of boats I deal with? IMO, NO..

Ask your what the fuel consumption in GPH is on a Dodge truck is pulling a horse trailer down the hwy at 65 MPH.. Ever thought about it? Hmmmmm, 14 MPG and going 65 MPH? Dump the trailer and now you at are 19-22 MPG.. Think about it.. Now add some seawater, and other crud that always seems to find it’s way into boat fuel tanks, and you see what I said NO..

What’s your GPH per engine at a solid 23-26K cruise?

Tony

[Justin Riege]

Thanks Philip

And here is a Video on the SMX Double Double

[Philip]

Not familiar with the FASS, but have you seen this?.

https://www.sbmar.com/product-category/fuel-systems/fuel-filtration-kits/

Simple, very effective, easy to service, and easy to get filters anywhere….

[Author]

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