Fuel Filtering System

A minute of your time if I could…

I’m gathering the bits and pieces for my fuel system and could use a couple of pointers.

So far I have two 52 gal. Moeller wing tanks connecting to a 150 gph Separ Fuel Polishing (SFP) system. I’ll use the pump on the SFP to clean the fuel in the wing tanks as well as transfer filtered fuel to a 30 gal. day tank. I want to then put in a dual filter arrangement between the day tank and the engine. There is of course, a final factory installed filter on the engine itself. All fuel returned from the engine goes back into the day tank. The fuel flow to the engine is approximately .2 gpm. Here are my questions.

1. While I got a deal on the SFP system, I am not excited about shelling out another $800 or so for a top-of-the-line dual Racor fuel/water separator to install between the day tank and the engine. Since the fuel will have already been run through the SFP and no un-polished fuel will be added to the day tank, I’m thinking of some less expensive spin on filters. What do you think?

2. In looking at the dual filter arrangements I do not understand how air isn’t introduced into the line when you switch from a fouled filter to a clean one while under way. Can someone explain how this works?

3. What sort of priming device is recommended and how is it plumbed into the system?

4. The SFP system has includes a “Fuel Conditioner” module. What is the purpose of a fuel conditioner unit?

Any insight into this setup would be appreciated.

Best Regards to All,

Sea Jay

 

SeaJay,

I am not familiar with the polisher you are using, however the installation of these units in pretty standard. They are generally ignored with respect to the fuel going to the engine itself, and are treated as independent systems.

As for ignoring racor's... The purpose of the fuel filters is really not so much to prevent crap from getting into the engine, but to prevent the engines fuel filter from getting clogged. The small engine filters are notorious for being woefully undersized, are rated ad ~1 micron, and while they work fine, if you have any contamination will clog in minutes.

Racors act as pre-filters to the fuel to catch whatever is in the fuel stream before it gets to the engines filter. On large engines I always use at least four filters plumbed in two sets of filters (A 20 micron and a 10 micron per set). This allows me to operate on one set, and in the case of a clog immediatly switch to the second set so I can be under way as quickly as possible. It also allows me to replace filters while the engine is operating, and to use the fuel delivery pump from the engine to bleed the filter system after a change.

Yes it is an expensive system, and you may decide to go with just one filter, but you cannot reasonably eliminate it. If you do decide to go this route, do yourself a favor and place the filter somewhere easily accessible even in bad waves, and add an in-line pump (the little squeeze pumps will work) to prime the system in case of a filter change underway.

 

Hey SeaJay....I use a twin racor setup and never have any problem shifting between filters and having the engine pull air.

Make sure your filter assembly is fully bled of air before putting it in the "Stand By" ready to go mode.

As for primer pump I have none. only the primer finger lever on the engine fuel lift pump.

To change a racor filter I simply block off is valves, unscrew the top, take out old, pop in new, then top off the filter assembly with a cup full of fresh fuel and screw the top back on. Naturally you have the give the fuel lift pump a few finger lifts to eliminate the last of any air in the system before start up.

Once the fuel filter is bled and its selector valve is closed putting the filter in standby mode, its not possible to loose any fuel and create a air space. Check that your filter selector valve is indeed closed, seals are correct on the racor top and that you have bled the system.

 

Hi Seajay. No worries about the time. Glad to help, though we are going to touch on a sometimes controversial subject. First, It is helpful to know what engine you have. If it is new, i.e., common rail, forget Racor and never look back. If it is not common rail technology and you don't believe that you'll be going to common rail any time soon, then you've got a decision to make... Do you for some reason need to see a (sorta) clear bowl on a filter housing? Do you want better filter medium with Beta rating, easier change out, easier to keep uncontaminated, less complicated, less expensive to purchase...or do you want Racor, Dahl, or whatever because it seems the thing to do? I'm going to show you a picture of the filter set-up on my boat and depending on flow rate, I recommend that you copy it and do not spend the money on Racors. I cannot remember the model numbers of the filters - maybe the picture will show - but the first one is a bulk filter, a trash filter, if you will, and will catch the pop cans and chicken bones that find their way into your tank. The second one takes on down to ten micron, I think but the important thing is that it is Stratapore and will seperate water which will settle into the bottom and be drained out every day, by you. It shant be drained while running, that would require valving and a seperate independent setup. Your on-engine filter, the last line of defence for your $1,000 injectors and the health of your engine, is likely 2 micron and will very seldom require changing. The filters I show will keep that on-engine filter clean and dry, ready to catch that 1 little particle that happens to get through.



Fuel conditioning: Does it say "Algae X" on it? Does it say ANYTHING about algae? That should tell us something, as there is no algae in diesel. Bacteria, yes. Algae, no. Does it have a part of the word "magnet" on it? If so, don't bother - go ahead and lose it as nobody has demonstrated that it is anything but marketing magic. Anyway, if it has some benefit in some system (Aligning fuel molecules, like I saw one of them advertise? Come on!) It would have to be considered unnecessary in a system such as you are going to have - your engine will get everything it needs with CLEAN, DRY fuel and possibly a lubricity additive (More and more, maybe all, engine manufacurers now feel that ultra low sulfer fuel does not lubricate well enough, injector pintles, pumps and maybe piston rings). If the fuel conditioner has to have a component added or changed out periodically, it could be for lubricity and that is a different matter.

 

The above posts, I agree with. They apparently like Racors, I don't see the point. They will stop a lot of junk from getting to your last chance filter. They do not have as much capacity as what I showed you. The filters I have accomodate engines of 500 HP, or more. My drag pointer vacuum gauge shows only 3.4 inHg after three years. It could probably show 15 or 20 before the engine would be affected. If you want to add lubricity automatically, the second filter could be a FS 20000. If you have a serious water problem, Cimtek has a water absorbing filter to replace the second filter, as well. It will shut your engine down if you don't check your filter and allow water to accumulate.

 

It appears in the above picture that the twin filters cant be isolated.. as in ,Filter one working, filter two on stand by or in filter replacement, engine running mode ?

 

No, That would be a more complex system for boats running 24 hour days. Mine is a day boat and the filters are in series. Anyway, if the fuel is drawn from the lowest point of the tank, as it should be, in a sump in the tank, better yet, anything in the tank is immediately drawn out of the tank and caught in the filter. No waiting for a rough day to stir up sediment to clog a filter - get it up and out of the tank the moment it gets in there and there are no suprises. The key is drawing the fuel from the absolute lowest part of the tank. I took a load of water, sand and rustballs into this system one time. The WIF sensor sounded the alarm as I was leaving the harbor, I drained a little fuel from all three filters and there was water in all three. I looked at the drag pointer and it was up a bit from usual. I changed the second filter, ran it up to full load, took a bit of fuel from all three filters and there was water in the primary, checked again after a half hour and all was clean and dry. The point is, I found the problem within a few minutes of the dock and corrected it - there could be no more problem...
Well, that's not quite true - the engine has a fuel cooler (which I plan to remove for this reason as I run only in cool weather Alaska and never have a too hot fuel problem). The fuel cooler could potentially fail and dump water into the system. The WIF sensors would pick that up but, in any event, it wouldn't matter what filter you had - the alarm comes on and you drain the filter. If you didn't just take on fuel, you would have to expect that the cooler core failed and dumped water into the fuel.
A boat that is traveling for long distances on open water would make better use of a system that can be valved to a back-up. The thing with so many systems is that they have problems at exactly the wrong time (when they are in violent weather and the goobers slosh up into the fuel pick-up) and they may need a valved back-up for that reason - We certainly don't want to stop and change filters in vile weather! For a dayboat, I wouldn't have it any other way than what I have.

 

Ya..Ya gotta keep fuel tanks clean. Every two years I pop the tops off the tanks and clean them out...perhaps 20 liters of sludge and goo comes out. Its one good reason to have a clear view filter arrangement. You rapidly see junk forming as the tanks crud up.
Oh and your outboard motor style pump bulb looks like a great idea...cheap as chips and effective. . I cant get away with something like that because of regulations..

 

Michael, That looks like bacterial growth from here. Did you try killin it with a biocide? I've never had more than a tiny bit of that - could it be that I am always running and nothing has time to grow? I might have to rethink everything I said if my tank were manufacturing a problem like that - or does it come out of the supplier's tank? Anyway, how about adding poison every time the boat is going to sit for a while?
I believe that I get less water from the supplier if I fuel up when they are busy late in the day. Fueling up early in the morning gets you the water that settled out of the fuel at night.

 

Yah sure...I alway add the biocide when refueling. The problem is the places you pick up fuel. Many areas in which I navigate have sour fuel tanks and a hundred meters of sour pipes. Many times it comes onto the boat unfiltered, full of sediment. You get used to it and make it a regular routine to clean out tanks plus I have a very effective, small, gravity fed day tank with a little hand pump for vacuming up bog.
Last season I used the starbright product for treating tanks ....dont know if its any better than the rest...Ill find out next tank clean.

Good idea to have jumbo fuel tank removable tops. I can do a two tank clean routine in a day...with some cups of coffee and not making a big mess of it.

 

Just to make a note what was discussed in the minimum passagemaker thread about the range and the places where you fil'r up.
No fence of course..

 

Stumble,

The polisher is a Reverso 150GPH Separ Marine unit.

http://reversopumps.com/fuel-polish...es/fuel-polishing-system-150-gph-separ-marine

It will be independent of the rest of my fuel system in that it isolates the day tank from wing tanks. No fuel will enter the day tank without first passing through this polishing system. (I will plumb in an emergency bypass) However, its primary function is to polish the fuel in the wing tanks, and from them, fill the day tank.

With 4 filters you have gone a bit beyond what I am proposing to do, but the concept is the same, switch from one filter (or set) to another while the engine is running. Remember, the duplex filter under discussion is after the day tank so all fuel in the day tank has already passed through the polisher at least once.


Michael,

The operation you described pretty much answers my question about the changing out the Racors, but just to be clear, this can be done while the engine is running, correct?

Mark,

You have gone to the heart of the matter and made me focus on what I am actually trying to achieve. For the most part, the boat will be in “day boat” use although there will be occasional multi-day runs. (BTW, the engine is a Beta 75) I think the ability to switch to a standby filter while underway is pretty cheap insurance for just the addition of a few valves. Your question about wanting the “Racor, Dahl, or whatever because it seems the thing to do?” is right to the point. What I am wondering is if the cost of the big Racor / Dahl / etc. water separator filters is warranted after I’ve already passed the fuel through the fuel polishing system into the day tank. I was envisioning the option of using filters similar to those shown in your photo, but not plumbed in series, rather in parallel. At the point in the fuel system where I want to install these filters, I’m expecting the fuel quality to already be pretty good. What I want is a quick, easy, and foolproof way to switch to a standby filter. If it cost less than $800, so much the better. I don’t mind spending money on systems I feel are necessary, but I do like to give some thought to what I am really trying to accomplish.

I’ve e-mailed Reverso about the “fuel conditioner” and will let you know what they say.

Strangely, the Beta “on-engine” is a 30 micron filter. I double-checked with Beta and they confirmed. My plan was to run a 30 in the polisher, 10s in the duplex, and maybe think about a 2 for the engine itself.

Everyone – Thanks for the input!

 

Yah..sure, change over , no problem..

This is a picture of a my present setup. Its very typical. one filter is "on line"...the other isolated and on standby. Never any air problems.

Perhaps have a look at the Racor website. They might have additional hardware, valve, layout suggestions.


As for Filter density..2, 5, 10 micron , everyone has a different approach. I like fine primary filters to protect my expensive secondary filters. Best consult your engineer.
Racor drop in filters are cheap. I go thru a dozen per year.

 

Mark,

Well I checked the fuel conditioner and sure enough it says "Algae X". I went to their website and found this...

"ALGAE-X® Technology reverses the agglomeration process, optimizing fuel quality by reducing the size and mass of fuel droplets. This provides peak engine performance while extending engine maintenance and filter change intervals and reducing harmful emissions & carbon deposits. ALGAE-X® Fuel Conditioners are self-cleaning, have no moving parts, require no electrical hookup, and are maintenance free."

I'm kinda with you on this. Sounds a bit like voodo, although I like the part about no moving parts and maintenance free Well I've got one of these critters so we'll just see if it does anthing.

 

It won't hurt. Kinda like the guys that wear a magnet bracelet, I think. Please let us know if they say anything about breaking up asphaltines with the magnets...just curious. Smaller droplets? ohhh-kay, but let me just say that I think they make quality fuel filtration. Polishing is just high rate "filtration" with an engine-independant fuel pump, right? I guess I see that - you get rid of your gremlins before you even leave port with a polisher. It seems like a bit of overkill but you can't have too clean of fuel! I think you are on the right path. For someone else (me included when buying questionable fuel), check this out as a means of not letting the crud even get on your boat; http://www.practical-sailor.com/sample/Fuelfilter.html
Michael, nice lookin' engine space.