Fuel polishing

[James S]

Extemp
I think the color coding sounds like a real winner.
There are some valve alternatives that may also help, like one that looks like two three ways stacked on top of each other that operate with a single handle/movement.
This is some info posted by Gord on a previous thread “Dual Fuel Tanks”

GROCO MARINE PRODUCTS
Select PRODUCTS, then VALVES

[sbmar]

Try this search in GOOGLE "Multi-Stage Fueltration" for some solid and proven info on setting up your marine fuel systems to where you'll never have any issues..

[Pblais]

Try this search in GOOGLE "Multi-Stage Fueltration" for some solid and proven info on setting up your marine fuel systems to where you'll never have any issues.

Not all problems are about fuel filtration. I'm not seeing any serious evidence that filtration beyond the ordinary has any benefit. A basic engine has two filters already. If you have ever had to track down an air leak from an overly complicated fuel system you might think otherwise. They are nearly impossible to find quickly and they shut down the engine in seconds only to reappear again.

[DeepFrz]

Paul's post brings the discussion back to my mantra: keep your polishing system separate from your engine supply system. You don't want to complicate your engine fuel supply system.

[Extemporaneous]

Originally Posted by James S

Extemp
I think the color coding sounds like a real winner.
There are some valve alternatives that may also help, like one that looks like two three ways stacked on top of each other that operate with a single handle/movement.
This is some info posted by Gord on a previous thread “Dual Fuel Tanks”
GROCO MARINE PRODUCTS
Select PRODUCTS, then VALVES

I was very excited the first time that I saw this valve, unfortunately it just doesn't do what I needed done. It actually takes away from some of the versatility.

Thanks,
Extemp.

[James S]

I used it for my tank selection since it does the supply and return at the same time.
Originally they were separate and you could actually move the fuel around by dumping the return into another tank.....but that meant it was possible to over fill one tank.

[Extemporaneous]

Originally Posted by James S

I used it for my tank selection since it does the supply and return at the same time.
Originally they were separate and you could actually move the fuel around by dumping the return into another tank.....but that meant it was possible to over fill one tank.

That's the versatility loss that I was speaking of. I do want be able to move fuel between tanks (although that will not be the normal mode of operation). I will have overflow paths where if it overflows it will go into the other tank. This is just the fail safe as the tanks could become somewhat pressurized (particularly if returning to the lower main tank) in that situation. Some important points to consider are watch the fuel gauges and the over flow needs to be below the vents for the tanks.

Regards,
Extemp.

[James S]

Sounds like you've thought this through.
Where/how are you terminating your tank vents?

[Roy M]

I use the twin Racors with a selector switch between them. The output then goes to a 2 micron filter in a Racor, since the fine filter on my engine is hard to access. Prior to entering the injector pump, there is a tee fitting and a piece of vacuum hose which leads into a Racor vacuum gauge, visible at the helm position. Underway, when the gauge begins to go "yellow", I can go below and switch over to the clean filter (previously bled of air).

My 55 gallon tank has LARGE cleanout ports above each side of the baffle. I run my tanks empty, from time to time, scoop out the remaining fuel, and wipe the tank sides dry with cotton diapers. Then refill with fresh, CLEAN fuel (pump some into a large clear jar to inspect).

I will be carrying a 55 gallon fuel bag when I go cruising, as well as a portable filter unit and 12 volt transfer pump. When not in use, I can transfer the fuel from other folk's tanks and perform a real polishing to make some bucks or brownie points. And when, not if, I get a batch of marginal fuel, I can make the best of it.

The leftover crap, along with spent motor oil, old paint solvents and other tired combustibles, can get poured over the pile of plastics from the trash and ignited in a hole with a very hot fire. The resulting residue would be largely converted to CO2 and oxides of nitrogen, halogens and other yucky things which would get converted into more stable forms more quickly and less poisonously than being captured in the Great Pacific Gyre, or the freshwater table under a landfill. That is, of course, when one is in the back of beyond, and not next door to a proper recycling center. I guess this ought to have been the subject of anther thread, though.

[Extemporaneous]

Originally Posted by janders

Hey all,

I'm interested in putting a fuel polishing system in place on our Caliber 40. We're going to be cruising far afield (Mexico for starters) where we'll get all sorts of bad fuel. We'd like to avoid fuel problems if possible.

Here's our current fuel system. We have a 55 gallon fuel tank (non-LRC Caliber 40). We have parallel Racor filters on the suction side of the lift pump. After the Racor outlets, we have a T in the fuel line leading to a little 12v pump that feeds our bulkhead diesel heater.

What I'd like to do is put in a T-valve after the 12v pump and run a line from the T back to the fuel fill or tank vent lines. I don't know much about the 12v pump other than it's just something that the PO picked up at Napa.

Anybody have a guess on what sort of PSI I'd need on the pump to pull the fuel through the Racors and get a decent enough flow to spin the particles out? Anybody know how to calculate the volume of flow so I know how long to run?

Another idea I've considered is putting a 2 micron element in one of the Racors and use that for polishing and as a backup. Then leave a 10 micron element in the other Racor and use that as the primary filter for the engine. I could still hot swap to the 2 micron Racor if I needed to although I don't know if the lift pump on our engine could pull fuel through a 2 micron element.

If you have any other feedback/experience with this type of system, I'd love to hear it. One bit of advice I got from diesel engine class teacher was to not polish fuel while running the engine since the polishing tends to aerate the fuel. Would not have known that.

Here's something I drew up in my boat notebook along with some notes from the discussion I had with my teacher.



Thanks!

Jason
s/v Hello World

Hi Jason,
First I hope the dialog in this thread is consistent what you had hoped for with your post/question. I can certainly bud out if you think my posts are off base in terms of what you were looking for. Let me know, I won't be offended. PM me if you want to spare my feelings.
I've been asking questions and reading and applying my own logic and reading and asking questions for a long time now and I can tell you there is a LOT of different opinions out there. I'm sure most are valid when compared to their personal experiences. All that to say, I think you will have to decide what level of protection it is that you want, how much money you are willing to spend, the level of complexity your willing to deal with along with the amount of space you are willing to dedicate to the system.
Some of my personal opinions (we know what that's worth) would be:

• If you can't afford to have something happen (dirty fuel) make sure it can't.
• From what I've learned dirty fuel is the NUMBER 1 reason why engines quit.
• I have NEVER heard of an engine dieing because the fuel is TOO clean.
• With sequential filtering (2 filters) you should be able to alleviate premature plugging of filter media so long as your filters are progressive (i.e. 10 and then 2micron).
• The more extensive your system is the more joints/connections that you will have and more potential leak points and so MUCH care will have to be taken making these joints.
• You need to consider the level of compromise you are willing to live with, likely consistent with your risk tolerance.
• The more complicated your system, the more thought you will have to put into the operation instructions in to make that as simple a possible.
• Turnkey systems are often behind covers and look nice but IF you ever had a problem with it you will find it hard to work on. It could have soldered joints, proprietary components, be VERY small (good and bad) and may not do exactly what YOU want it to do. They also are likely to have piping sizing of only 1/4" (may be okay depending on volumes).
• If you make your own system you will know EXACTLY how it works and it will likely be made with readily available replaceable parts.

Good Luck and Best Regards,
Extemp.

[David M]

I would completely isolate the fuel polishing circuit from the engine fuel circuit. Even with dual Racors, the engine filters should be dedicated just to cleaning the fuel right before it goes to the engine. More importantly, if your fuel polishing circuit develops a vacuum leak or screws up in some other way, it will not affect your ability to use the engine.

Also, if the fuel polishing circuits discharge back into the tank is placed at the bottom of the tank, it wont create bubbles....unless your tank is nearly empty.

[DeepFrz]

David brings up a good point. Ensure the return line extends to close to the bottom of the tank so as not to aerate the fuel.

Anyone interested in a fuel polishing system might want to read the article in the June 2007 Passagemaker magazine. There were also a couple of articles in previous issues about "What's in my Tank?" and "Overcoming dirty fuel offshore" that might be of interest.

[Extemporaneous]

Originally Posted by David M

I would completely isolate the fuel polishing circuit from the engine fuel circuit. Even with dual Racors, the engine filters should be dedicated just to cleaning the fuel right before it goes to the engine. More importantly, if your fuel polishing circuit develops a vacuum leak or screws up in some other way, it will not affect your ability to use the engine.

David,
Hard to argue your logic, impossible really. I just can't have it all. Trying to pick the right compromises and include the right contingency plans is really the exercise for those of us that can't have it all. Unfortunately only time will tell. Don't take this to mean that I'm discounting your points.
Having said that, due to other consideration I've chosen to put my polishing pump on my regular fuel circuit in order that it could be used as a backup engine fuel pump. Only the future will tell if this is a HUGE mistake, it certainly could be. I do though have a plan if leaks develop in my system at inopportune times (which would be any time). It would take about 4 minutes to put in place. At the first and last connections to the filtering system I have put flare fittings and with a premade hose on the wall at the filter system location, I could with this and the wrenches also on the wall bypass the entire filter system in which case the only filtering at that point would be done by the stock engine filters.
It is clear the you are strongly advising against a mixed system. Is there more that you can say or provide in terms of the amount of vacuum leaks you've seen and or heard of (I guess how common they are). This is certainly something that I am aware of and will be watching for.

Originally Posted by David M

Also, if the fuel polishing circuits discharge back into the tank is placed at the bottom of the tank, it wont create bubbles....unless your tank is nearly empty.

Good point. I'll have to check what the return lines are doing now and adjust if necessary.
Comments?

Regards,
Extemp.

[David M]

I'm not strongly advising anything. I'm just throwing out there what I think would be the ideal way of going about it. Boats though are a compromise of all kinds of things and they have to set up according to what is best for the end user. Your design will work just fine I believe. Its just a matter of doing what works best for you.

[Extemporaneous]

Originally Posted by David M

I'm not strongly advising anything.

Opps, my interpretation of what the message was, excuse. Regardless what you're saying are very good points.

Originally Posted by David M

I'm just throwing out there what I think would be the ideal way of going about it.

Comments from people like your self have combined to become my current plan. Thank-You Everyone.

Originally Posted by David M

Boats though are a compromise of all kinds of things and they have to set up according to what is best for the end user.

Ain't that the truth.

Originally Posted by David M

Your design will work just fine I believe. Its just a matter of doing what works best for you.

We'll see and I hope so. Time will tell.

Regards,
Extemp.