Fuel filtration, lessons learned

[sunchaser]

Bladder and deck tanks are sometimes used to extend range for a delivery. They are a PITA. There are also concerns about trim given they are often placed in an open cockpit or Sundeck since few folks want them on their cabin sole. Transferring fuel in open water can be a challenge and is messy - most boats have deck-fills. Fuel bladders are pretty heavy and robust. Rolling up and stowing isn't as convenient as it sounds. Possible, but barely practical as a range extender. A year or so ago, someone asked about getting a Hatt 60-ish across the Atlantic as they were moving. That's a rare example where a bladder or barrels might make sense.

In my opinion, bladders and barrels are a good example of stuff that looks good on paper and should go no further.

Peter

It depends on the vessel and mission. We know people that have had as many as 12 50 gallon drums or the plastic enclosed totes carrying about 600 gallons.on the aft deck. In these cases I’m referring to long transpacific journeys.

The cases I’m referring to are +75’ Northern Marines or Nordhavns with very smart Captains or owners.

I’ve seen sail boats in the PNW with up to 10 5 gallon jerry cans lashed on deck. The distance between fuel fills exceeds their small tanks, plus they don’t like to raise sails.

Our DF 48 has two aft tanks at 100 g each. A 50 g drum or tote could easily fit above each tank and deck fill with no vessel overload issues.

 

[mvweebles]

It depends on the vessel and mission. We know people that have had as many as 12 50 gallon drums or the plastic enclosed totes carrying about 600 gallons.on the aft deck. In these cases I’m referring to long transpacific journeys.

The cases I’m referring to are +75’ Northern Marines or Nordhavns with very smart Captains or owners.

I’ve seen sail boats in the PNW with up to 10 5 gallon jerry cans lashed on deck. The distance between fuel fills exceeds their small tanks, plus they don’t like to raise sails.

Our DF 48 has two aft tanks at 100 g each. A 50 g drum or tote could easily fit above each tank and deck fill with no vessel overload issues.

No doubt it's possible and it's done from time to time. But just think about the logistics involved - there are no racks for 50-ish gal/300# drums like there are for dive tanks. It is a "Plan B" (or C or D). Used as an interim reservoir for fuel polishing is a table-top exercise.

BTW - the Willard 36 that went from California to Hawaii in 1987 carried 300g in her main tanks. I forget how much she carried in a bladder (over 100g) but only burned around 325g for the trip.

Peter

 

[Lepke]

Submarines in WWII used some of their ballast tanks for diesel fuel on long range patrols. But they had equipment to separate out any water. Remaining fuel in the tanks was flushed into the ocean in the glory days of no EPA. Also in WWII, destroyers used sea water for ballast when fuel tanks were low and they were in heavy seas. But is was time consuming to remove left over water from later fuel. In Halsey's Typhoon, 3 destroyers sank that were known to be low on fuel and didn't take on water ballast. Others that did, like the Caine, survived.
I cruise with a case of each fuel filter size. I went to 2 micron primaries years ago. Having really clean fuel has benefits for things like injector pumps and mechanical injectors that have many tight tolerances. I haven't changed an injector in my Detroits in over 10 years.

 

[tvtfc]

^^^
Ah yes. That jogged my memory. It was some long-ago thing I ran across about submarine design. I suppose that submarines have less of a tenancy to experience conditions which would cause agitation...excepting maybe depth charge attacks.

I never read anything about the Halsey typhoon story or the various vessels involved in it. Probably I should one day. Sounds a pretty good object lesson in centers of gravity and the like if one should end up on the bitter edge.

Are there any fuel injection systems which you would feel would be particularly tolerant of or particularly sensitive to different types of fuel contamination in terms of rapid wear? One boat I ran across had a seemingly replaced pump on some Polish engine. I'm guessing that it might have been a real bear to find the unit. IIRC the vessel had a single engine and no limp-home capability either.

 

[Delfin]

^^^
Ah yes. That jogged my memory. It was some long-ago thing I ran across about submarine design. I suppose that submarines have less of a tenancy to experience conditions which would cause agitation...excepting maybe depth charge attacks.

I never read anything about the Halsey typhoon story or the various vessels involved in it. Probably I should one day. Sounds a pretty good object lesson in centers of gravity and the like if one should end up on the bitter edge.

Are there any fuel injection systems which you would feel would be particularly tolerant of or particularly sensitive to different types of fuel contamination in terms of rapid wear? One boat I ran across had a seemingly replaced pump on some Polish engine. I'm guessing that it might have been a real bear to find the unit. IIRC the vessel had a single engine and no limp-home capability either.

I know the Hamiltons are using fuel bladders they store on the stern deck on their Nordhavn, but I can't imagine dealing with it in a seaway. I guess you wait for a calm day....

 

[Snapdragon III]

I used an 80 gallon gasoline bladder on a 25' fishing boat I had about 10 years ago. It was sweet. I repiped the fuel system so I had a dedicated tee for it with a special fuel quick disconnect. All I had to do was fill it up, snap on the fuel line, and change a couple valves. I would burn the fuel in the bladder first, then roll it up and put it away. It allowed us to do a couple of big adventures that would not have been possible otherwise. To be practical on a cruising yacht you would have to havre really strong tie downs installed for it. I could see putting around 3 days of fuel on deck on a long passage. Modern weather forecasting is pretty good, and you would be unlikely to be surprised by something really nasty before you burned it up in the first few days of your trip.

50 gal barrels seem like a nightmare. I couldn't imagine how you could tie them down so they would be safe on most boats. Getting the fuel out of them would be a huge pain in the ass too if the weather wasn't perfect. When I was buying my boat and thinking about getting it home from Fiji I briefly thought about adding some barrels. I was surprised when I did the math and realized that the tanks in the boat held 33 50gal barrels worth of fuel! It made the thought of a couple extra ones slamming around on deck seem stupid.

 

[Simi 60]

We did a delivery on a 65 ft passenger ferry catamaran that used 1000 litre IBC cubes for spare diesel

Also did one on a fishing boat that had multiple blue plastic barrels along the side decks.
It also had deck fillers that were often awash so water was making it into the tanks but the 1000fg handled it with frequent draining and, that vessel had an 855 natural so can run on vomit.

 

[darkside]

A 500l bladder worked just fine and allowed us to travel much faster and skip ports we weren't much interested in. When we got there, we rolled it up and stowed it.
I've also used the 1000l cubes on larger vessels.

 

[mvweebles]

But would you use a bladder/barrel solely to stow fuel while you polish it, the 'tap root' of this thread diversion? As TT pointed, a deck-mounted Day Tank?

Peter

 

[rslifkin]

Drums work best on a boat with a cockpit that can handle the weight aft. They can be strapped against the cockpit walls. On a flush deck, they'd be a nightmare to secure.

 

[pjtemplin]

The fine folks on MV Dirona have several posts on their blog/website regarding fuel and filtration. Of note, they mentioned that the prevailing wisdom is to filter progressively smaller as you get closer to the cylinders: coarse filtration first, medium filtration (the classic Racor pre-filter) second, fine filtration last (the classic on-engine filter). Yet as many have mentioned, changing that on-engine filter requires shutting down an engine (and in obvious scenarios, sometimes that's the only main engine) to do so. Their approach seemed to be coarse/fine/medium/fine, so that fuel had passed through a 2 micron filter (at least) once before getting to the on-engine filter, and by doing so they had a lot more freedom to change out the first tier of fine filters without interrupting the engine.


YMMV, take this at your own risk, go read their blogs for more details and to see if I've fuzzied up any of the details.

 

[psneeld]

Fuel filtration isn't rocket science and you don't need a bunch of opinions that aren't supported in all situations.

To design your system, you start with fuel off the boat and get to what your engine needs.

If you fill from 55 gallon drums rolled down the beach and have no idea of it's history.... may have to put a lot of thought into your progressive filtering.

Go between NJ and Florida as a snowbird with an engine that only uses and passes 2 gal/hour.... you can use 2 micron primary and secondary and go 20,000 miles with a filter change every year or two and never have a problem.

There are plenty of reasons for me to have changed that routine, but I never needed to.

So just think through what your routine will be and set it up accordingly....for both the filtration and ease of changing when needed.

Any "recommended" system from someone who doesn't know you, your boat and your routine is like going to a clairvoyant.

 

[TBill36]

My Racors have a vacuum gage with drag pointer. I've got some fuel issues so have been running 2 micron filters in the Racors and changing them as the vacuum starts up the green scale.

Since I know the vacuum range at the primary stage, I feel it is better to catch it there than the secondary on the engine where I don't know it. Why would I want to wait and have an unknown fuel restriction at my secondaries instead of at my Racors where I know to change them.

 

[Steve DAntonio]

. Yes, and for the reason mentioned. Changing the OEM at sea means shutting the engine off, which can get pretty rambunctious depending on sea conditions. My Racor 500s are on a manifold, so I can swap one out while underway. I guess my main lesson is protect the OEM filter at all costs since it has to be screwed in or the engine don't run, nor does it if that filter is clogged.

From time to time I encounter an engine with tandem secondary fuel (and oil) filters, which allow underway replacement.

 

[Simi 60]

All this 2 micron talk.

Is the nta855m Cummins the only engine with 20mic on engine filters?
Can't see any reason for us to go finer than 10mic in the dual 1000fg if the final, on engine filters are 20 mic.

 

[rslifkin]

All this 2 micron talk.

Is the nta855m Cummins the only engine with 20mic on engine filters?
Can't see any reason for us to go finer than 10mic in the dual 1000fg if the engine filters are 20 mic.

If Cummins felt 20 microns was good enough, then filtering to 10 is probably just fine. Although as Lepke pointed out, there's some potential for longer lifespan of injectors and such with even cleaner fuel. So filtering to 2 microns may have some benefit, just not enough that Cummins felt it was necessary to get adequate life out of the fuel system components.

 

[Simi 60]

If Cummins felt 20 microns was good enough, then filtering to 10 is probably just fine. Although as Lepke pointed out, there's some potential for longer lifespan of injectors and such with even cleaner fuel. So filtering to 2 microns may have some benefit, just not enough that Cummins felt it was necessary to get adequate life out of the fuel system components.

I guess I always thought a 2 might be restrictive given the high fuel flow in our fuel system.
And, if there did happen to be some crud in the tank, a 2 would be clogging fast.

 

[Delfin]

From time to time I encounter an engine with tandem secondary fuel (and oil) filters, which allow underway replacement.

That's pretty sweet...

 

[TBill36]

Simi you hit the trip wire. I don't understand it, but the flow rate for a given filter is not supposed to be affected by the filtration grade, ie, a 2000 series racor at 30 micron has the same flow rate as a 2 micron. The 2 will clog faster, but starting out they should be the same.

 

[tvtfc]

Simi you hit the trip wire. I don't understand it, but the flow rate for a given filter is not supposed to be affected by the filtration grade, ie, a 2000 series racor at 30 micron has the same flow rate as a 2 micron. The 2 will clog faster, but starting out they should be the same.

I would suggest that the 'size' of filters are so far off the scale in the overkill direction that flow rate observations are simply not of consequence for most common uses cases (such as a small diesel engine with a typical return rate.)

Assuming equivalent filter surface area (or more accurately, pore area) you would probably note a decreased flow if you started progressively increasing the supply pressure and getting high flow rates. Or increased the viscosity of the oil. In fluid resistance, things tend to start to get exponential with respect to velocity. I wouldn't stake my life on that hypothesis though.

Of course it is exactly true that the finer filter would clog up faster if used as a primary, but on the other hand, so what? Just being able to monitor something as it deteriorates seems pretty worthwhile to me. I like your strategy here whether it breaks standard orthodoxy or not, and it seems to be working for you. Thanks for sharing as it made me think a little rather than 'go with what I know.'

 

[O C Diver]

Simi you hit the trip wire. I don't understand it, but the flow rate for a given filter is not supposed to be affected by the filtration grade, ie, a 2000 series racor at 30 micron has the same flow rate as a 2 micron. The 2 will clog faster, but starting out they should be the same.

I'm not sure that the flow rate is based on 30 microns. My racor 1000 fuel polishing filter sees about 150 GPH and is rated for 180 GPH. Whether using a clean 2 micron or 30 micron filter, I have the same vacuum level on my vacuum gauge. It may be the internal plumbing design that limits flow rate until the filter starts to become significantly fouled.

Ted

 

[rslifkin]

I guess I always thought a 2 might be restrictive given the high fuel flow in our fuel system.
And, if there did happen to be some crud in the tank, a 2 would be clogging fast.

Higher flow rate just means you need bigger filters to maintain adequate flow rate and not clog too quickly.

 

[Capt Dan]

Some recommend installation if inline fuel pump which is fuel purpose.
1. Helps when bleeding fuel system
2. Will allow you to run on a dirty fuel filter longer, possibly much longer.

 

[Southern Boater]

I know the Hamiltons are using fuel bladders they store on the stern deck on their Nordhavn, but I can't imagine dealing with it in a seaway. I guess you wait for a calm day....

Their preparation video prior to departure from Maine (or somewhere in the N.E. US??) to Ireland, showed the fuel bladders could connect directly to the engine room fuel manifold as soon as they were filled at the dock, and prior to departure. An excellent arrangement, just open and close a couple of ball valves.

BTW, the bad fuel situation was bad news for sure, but got to say, it only seems such a short time ago you were heading across to Hawaii, and now you are back!
Impressive amount of sea miles for sure

 

[Delfin]

Their preparation video prior to departure from Maine (or somewhere in the N.E. US??) to Ireland, showed the fuel bladders could connect directly to the engine room fuel manifold as soon as they were filled at the dock, and prior to departure. An excellent arrangement, just open and close a couple of ball valves.

BTW, the bad fuel situation was bad news for sure, but got to say, it only seems such a short time ago you were heading across to Hawaii, and now you are back!
Impressive amount of sea miles for sure

I seem to recall they had some issues with tying them down. I imagine it would be quite exciting to deal with that in a seaway. I'm just grateful that Delfin is basically a floating fuel tank, so I'll never find out how well bladders can work.