Do you fuel polish?

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The PO of our boat went through the angst of replacing the fuel tanks. I guess he thought "never again" and put the polishing system in at the same time. I would never make the case that it's necessary, particularly with new fuel tanks, etc. I have it and I use it, but I'd never install one.


Jim
Sent from my iPad using Trawler Forum
 
Capt.Bill11 said:
No. It's a waste of time and money in most cases.
Click to expand...


It's a marketing scheme to sell boaters things they don't really need. If your buying clean fuel and you're maintaining the orings on the deck fills to keep water out your normal primary and secondary filters do the job without need for a polishing system. Then change your filters on a schedule or use vacuum gauges. If you're in a 3rd world country and the quality of fuel is suspect then the investment may be worth it, the large majority of TFers are not cruising in areas where contaminated fuel is a problem, save your money for something worthwhile.


Sent from my iPad using Trawler Forum
 
JDCAVE said:
I have it and I use it, but I'd never install one.
Click to expand...
That's the kind of experienced feedback that makes more sense than anything. I gather polishing the fuel is just an excuse to take a cold beer into the ER after the clock and barometer are done.
 
Hawgwash said:
Obviously after 25 posts with no "best invention ever" comments, that was going to be my next question.

These systems seem to be relative newborns. I wonder if they really do much and how work boats managed for a century without them.
Click to expand...

There is nothing new about these systems.

And real boats use Afla Laval's. :D
 
Yes we fuel polish with a Gulf Coast system. Yes the filter when changed is dirty with ashfaltum and the filter element has picked up any tank condensation that gets into the fuel. The Volvo TMD 31A thankfully doesn't burn a lot of fuel per hour so going thru the 280 gallons of fuel in the tank is lengthy, that's when the organic nature of diesel fuel has problems. If you have a high usage engine and you cycle thru a lot of fuel you probable don't need to polish.
 
I would much rather have a tank cleanout port than a fuel polishing set up. Regularly serviced tanks with good filtration gives peace of mind.
 
My peace of mind is changing the Racor annually not because it's dirty, because the paper filter element is only good for so long.
 
Hawgwash said:
I talked to two long time GB owners recently who have never polished their fuel.

Do you?
If so, how and when?
Click to expand...

The previous owner had a fuel polishing system of sorts included in the complete re-tanking and re-plumbing (fuel) of the boat the year before we bought it. So this was in 1997. We have never used the polishing system and have had no need to. We have never gotten any water in the bottom of the Racor bowls and the filter elements coming out look just like the filter elements going in other than the old ones are dyed red from the fuel.

I attribute this to our harbor's fuel supplier having clean tanks and a very high fuel turnover, that we use the boat year round and manage our tanks so fuel does not sit very long in any of them, and the fact that our entire five-tank fuel system drains via gravity from the lowest point in each tank. No pickup tubes and no pumps other than the mechanical lift pump on each FL120. So when a tank is empty, it's totally empty.
 
sunchaser said:
Just changed out the 30u primary fuel filters after 18 months and about 1500 gallons each of net fuel burn. Filters were surprisingly clean with some sediment in the bowl.

Carl, I'm certainly in favor of clean fuel. Each vessel is different in design and capacity of tanks, age of same, yearly fuel burn and filter system. The OPs question was what do we have, so I duly reported.

BTW, I'd have guessed today's ULS fuels to have less asphaltenes than a few decades ago fuel's. My tanks never have seen high sulfur fuels, could this be a benefit?

I've recently been on some vessels with Alfalaval centrifuges. The gunk they pick up is astounding. But with old tanks and fuel burn measured in tens of thousands of gallons per year, ALs seem prudent
Click to expand...
Not sure about the chemistry, but ULS fuels produce more, not less precipitants. Worse when the fuel is heated, as it is when run through the return line.
 
Guess I should add that when I bought the boat, there was a fuel transfer system in place to trim the boat between the two 350 gallon tanks. Converting the transfer system to a fuel polisher essentially cost $300 for a Racor 1000 filter and a few fittings. For all the frivolous stuff we spend money on for our boats, don't see how anyone can argue with $300 to convert it to a fuel polisher. How much I use it remains to be seen, but certainly nice to have if I ever get some dirty fuel.

Ted
 
I set up my system so that the day tanks are filled via the fuel polishing system, primarily as I anticipated getting fuel in developing countries or from small islands etc

So far I've only fueled in USA and Australia and after 8,250 litres through the polisher I'm still on the original filter, no backpressure of any consequence so I have left it in place. So all my fuel intake has been clean.

Given that even in developing countries no-one wants engine failures or unreliability I may have been over cautious but nonetheless I think its a cheap precaution to use a polisher.
 
O C Diver said:
Guess I should add that when I bought the boat, there was a fuel transfer system in place to trim the boat between the two 350 gallon tanks. Converting the transfer system to a fuel polisher essentially cost $300 for a Racor 1000 filter and a few fittings. For all the frivolous stuff we spend money on for our boats, don't see how anyone can argue with $300 to convert it to a fuel polisher. How much I use it remains to be seen, but certainly nice to have if I ever get some dirty fuel.

Ted
Click to expand...


Two questions:
--Will your existing tank pickups completely empty the tank?
--I your new filter getting fuel via suction or pressure?
 
sunchaser said:
Two questions:
--Will your existing tank pickups completely empty the tank?
--I your new filter getting fuel via suction or pressure?
Click to expand...

The pickups for the engine and generator are about 4" off the bottom of the tank. Due to the shape of the tank, they will draw 98% of the content out.

The pickups for the fuel polisher will likely leave less than a pint in the tank.

The Racor is on the suction side of the pump. Fuel goes through the Racor before it reaches the pump.

Ted
 
O C Diver said:
Guess I should add that when I bought the boat, there was a fuel transfer system in place to trim the boat between the two 350 gallon tanks. Converting the transfer system to a fuel polisher essentially cost $300 for a Racor 1000 filter and a few fittings. For all the frivolous stuff we spend money on for our boats, don't see how anyone can argue with $300 to convert it to a fuel polisher. How much I use it remains to be seen, but certainly nice to have if I ever get some dirty fuel.
Click to expand...

This makes a lot of sense to me (but I generally know nothing). You already had the basics of a fuel polishing system so it is cheap and easy to add some filters.

On the other end of the spectrum, I have a 40 gal tank. For the past few years I have filled up with fuel once per year. Most of the time on the water we are under power but we don't burn a lot of fuel. Because of this my fuel tends to be very stale. I have not had a problem so far, but it is something that I think about on occasion. This year I put a vacuum gauge on my Racor just to keep an eye on things.
 
dhays said:
This makes a lot of sense to me (but I generally know nothing). You already had the basics of a fuel polishing system so it is cheap and easy to add some filters.

On the other end of the spectrum, I have a 40 gal tank. For the past few years I have filled up with fuel once per year. Most of the time on the water we are under power but we don't burn a lot of fuel. Because of this my fuel tends to be very stale. I have not had a problem so far, but it is something that I think about on occasion. This year I put a vacuum gauge on my Racor just to keep an eye on things.
Click to expand...

You will never see that gauge move.
 
Capt.Bill11 said:
You will never see that gauge move.
Click to expand...

We installed Racor's vacuum gauge on the Racor 500s in our fuel system that feeds our two FL120s. The FL120s don't draw much fuel and return almost nothing, so as Capt. Bill says, the gauges never move under normal operating conditions. The needles just sit at the bottom of the dial.

I suppose if the filter elements got really clogged up they might move off the pin and show something but even then I suspect it won't be much unless the restriction was very severe, at which point I wouldn't be surprised if the sound of the engines started cluing us in that there was a problem developing.

For engines that run a lot of fuel through their systems it may well be a different story. But for FL120s, at least, at our cruise rpm of 1650 the gauges do exactly as Capt. Bill describes---- nothing.

They look cool, though.:)
 
Has anyone had a breakdown that could have been prevented had your boat been equipped with a fuel polishing system?
 
Marin said:
We installed Racor's vacuum gauge on the Racor 500s in our fuel system that feeds our two FL120s. The FL120s don't draw much fuel and return almost nothing, so as Capt. Bill says, the gauges never move under normal operating conditions. The needles just sit at the bottom of the dial.

I suppose if the filter elements got really clogged up they might move off the pin and show something but even then I suspect it won't be much unless the restriction was very severe, at which point I wouldn't be surprised if the sound of the engines started cluing us in that there was a problem developing.

For engines that run a lot of fuel through their systems it may well be a different story. But for FL120s, at least, at our cruise rpm of 1650 the gauges do exactly as Capt. Bill describes---- nothing.

They look cool, though.:)
Click to expand...


Hmmmmm! Mine don't move either! Hadn't thought about this. I've got dual Racor 900's with a gauge.


Jim
Sent from my iPad using Trawler Forum
 
Disconnected the filters of my polishing system, but use its pump and related piping to transfer fuel among tanks and to prime the engine. Filters no longer used as they're unnecessary in my environment:

 
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I have read the entire thread. My bias, I have a fuel polishing system, very simple, I put in. I cruise in the Caribbean where the fuel is often not as clean as in Canada, the United States and Australia. Also the heat allows condensation to build and bugs to grow.

My thoughts in reading the thread is that the value/need for a fuel polishing system depends on the individual boat, where she cruises, how fast the diesel is used etc. If you are not in the tropics, burn through your fuel in a couple of months and have a pickup at the bottom of the tank, you probably don't need fuel polishing.

If you are in the tropics, with a slow boat, and buy fuel in bulk to save a couple of US dollars a gallon you will be storing fuel over the off season and find water and bugs in the tank.

To explain the buying fuel in bulk, St. Vincent (southern Eastern Caribbean) has a couple of small tankers anchored out which buy fuel in Venezuela and sell it in the harbors of St. Vincent. You can save $2 per gallon on a 300 gallon purchase. Hard to pass up that savings, especially when you can polish the fuel.

The sailboats in the Eastern Caribbean don't have the luxury of buying fuel only at one location. Frequently we hear of engines being shut down because of dirty fuel. Many times the tankage is 40 or 50 US gallons and fuel is bought several times a year in different locations. In some places it is actually pumped from a barrel.
 
"These systems seem newborn"

On larger boats there are fuel tanks not boxes for fuel. Many have access ports for hand removal.

Larger boats frequently will use a better filtering system. A pair is the norm.

The fuel is spun in a centrifuge , and all the dirt is cleared on a regular basis.

If the crap doesn't plug the line to the filter , it works.

The mfg A. Laval, now has a setup for more modest sized boats.





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I think as several have mentioned it's situational. Boat that never goes beyond the US coasts and the Bahamas, we don't polish regularly. However, every three years we do have polishing and tank cleanout planned when hauled. Boat that travels outside the US we have Alfa Laval and polish every gallon of fuel. Can't risk a bad tank of fuel in remote areas.

Now, something we haven't done yet is the loop and then out mid loop detours of keeping a boat on the TN river over the winter and then cruising there and other rivers. We do plan on a Alfa Laval for that. You may find yourself purchasing from a low volume marina during their off season or at the very start of spring before they've purchased any fuel for the year. When we lived on a small lake, every winter/spring there would be cases of water in fuel as one or another of the very small marinas. The marina that scares me is the one that is relatively low on fuel at the end of the season but doesn't want to spend the money for fuel they won't need for months. Then spring hits and they're selling out of that low tank.
 
Capt.Bill11 said:
You will never see that gauge move.
Click to expand...

Probably not, for several reasons. I can't watch it while under way, I am fortunate to be able to buy good fuel, and I change my Racor filter twice yearly now. I used to change the filter yearly but then I forgot one year. When I did change it, it was black and nasty. That is when I decided to get the vacuum gauge.

So far, I have gotten water out of the water separator only once in the 5 years I have owned this boat. I am fortunate to have had a good fuel source. However, my primary source went out of business this last year. Now my choices are more limited.

The only reason I got the gauge (very cheap really) was in the unlikely event that I get a bad batch of fuel combined with rough weather sailing that might start to clog my filter. I give the gauge indicator (It sets at the highest vacuum reached then has to be reset) a quick look the same time I check the oil and coolant level before leaving the dock.

The gauge is unnecessary in that I have never had a clogged filter that has caused my engine to quit and likely never will. Of course, the same could be said for my raw water sea strainer as it never has any debris in it, and it is unnecessary to change my impeller yearly as it is always in great shape, and the PFDs are a waste of space to keep handy since I have never fallen overboard, but I do all those things anyway for some reason.
 
mahal said:
Has anyone had a breakdown that could have been prevented had your boat been equipped with a fuel polishing system?
Click to expand...

I don't know if a polishing system would have helped, but in my previous boat (old 34 Mainship) I did unknowingly take on some bad fuel and had my engine stop 2 times due to fuel clogging...not the filter but the copper lines.
The "stuff" looked like large coffee grounds and the first time got stuck just ahead of the fuel manifold at a male flare fitting. The fitting had a burr partially blocking the ID. I found that rather quickly (luckily) and cleaned the fitting.
The second time was at the shut-off ahead of the Racor 900. Filter looked partially empty and I turned the handle to shut the fuel off so I could change the element and I felt a crunch, then fuel started bubbling into the housing.
After that I started draining the fuel bowl after every 10 hours or so and would collect those particles. Took a few years to clear the system out.
 
dhays said:
Probably not, for several reasons. I can't watch it while under way, I am fortunate to be able to buy good fuel, and I change my Racor filter twice yearly now. I used to change the filter yearly but then I forgot one year. When I did change it, it was black and nasty. That is when I decided to get the vacuum gauge.

So far, I have gotten water out of the water separator only once in the 5 years I have owned this boat. I am fortunate to have had a good fuel source. However, my primary source went out of business this last year. Now my choices are more limited.

The only reason I got the gauge (very cheap really) was in the unlikely event that I get a bad batch of fuel combined with rough weather sailing that might start to clog my filter. I give the gauge indicator (It sets at the highest vacuum reached then has to be reset) a quick look the same time I check the oil and coolant level before leaving the dock.

The gauge is unnecessary in that I have never had a clogged filter that has caused my engine to quit and likely never will. Of course, the same could be said for my raw water sea strainer as it never has any debris in it, and it is unnecessary to change my impeller yearly as it is always in great shape, and the PFDs are a waste of space to keep handy since I have never fallen overboard, but I do all those things anyway for some reason.
Click to expand...

Wifey B: I'm still stuck on your 40 gallons a year. :D 40 an hour, I'm familiar with.

Bet they were shocked when you bought the gauge before a clogged filter and not after.
 
Bay Pelican said:
I have read the entire thread. My bias, I have a fuel polishing system, very simple, I put in. I cruise in the Caribbean where the fuel is often not as clean as in Canada, the United States and Australia. Also the heat allows condensation to build and bugs to grow.

My thoughts in reading the thread is that the value/need for a fuel polishing system depends on the individual boat, where she cruises, how fast the diesel is used etc. If you are not in the tropics, burn through your fuel in a couple of months and have a pickup at the bottom of the tank, you probably don't need fuel polishing.

If you are in the tropics, with a slow boat, and buy fuel in bulk to save a couple of US dollars a gallon you will be storing fuel over the off season and find water and bugs in the tank.

To explain the buying fuel in bulk, St. Vincent (southern Eastern Caribbean) has a couple of small tankers anchored out which buy fuel in Venezuela and sell it in the harbors of St. Vincent. You can save $2 per gallon on a 300 gallon purchase. Hard to pass up that savings, especially when you can polish the fuel.

The sailboats in the Eastern Caribbean don't have the luxury of buying fuel only at one location. Frequently we hear of engines being shut down because of dirty fuel. Many times the tankage is 40 or 50 US gallons and fuel is bought several times a year in different locations. In some places it is actually pumped from a barrel.
Click to expand...

+1. If you have small tankage you burn through the fuel fairly quickly and aren't likely to go places where clean fuel isn't available. Add a few more gallons and of course there will be crud that precipitates out of the fuel over a year or so - and I guess you can hope it all settles to a proper sump for draining or you can clean it before it makes it to the engine. There must be some reason why all large ships have polishing systems and why there are people who make a living cleaning dude boat diesel tanks at $1,000 a pop, although I would have to think that they are not doing a lot of business with people who have polishing systems that cost less than 1 cleaning. Characterizing polishing systems as unnecessary frivolities seems a bit of a stretch, but I guess if you don't have one, or don't think you need one yourself perhaps that settles the matter for you for everyone else.

The OP asked if people polished their fuel. Answer - some do and some don't. Opinion - if you have 1,000+ gallons, and especially with a day tank, or cruise in third world areas then using a polishing system provides some peace of mind.
 
Kinda sorta. I have 5 fuel tanks one@ 150gal that is just storage and not plumbed to the engine .Two 55gal tanks and two 75 gal tanks . All the tanks are plumbed to the suction side of a 90gph pump pulling through a 900 racor seperate from my secondary and primary filters for the engine .The pump has a manual switch with a couple wires with alligator clips that I hook up to my generator start battery . I know it sounds funky and very redneck but this came with the boat.Wait it gets better . After the 900 racor and pump there is a long hose that I just keep rolled up with a plug in it . This hose will reach any of the 5 deck fills . I can send the fuel around maually from any of the
tanks . I'm not sure that I'm really doing much polishing but it gives us a little peace of mind . Joy handles the hose going to the full fills and I handle all the valves and switch. I do get a bit of an eye roll when I say we need to polish some fuel .
This should give ya"ll something to talk about .:popcorn:
 
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Our boat has a polisher as result of the fuel management system, but we also have a lowest point sump.

Were I building a new boat I would spec an Alfa Laval Unit, IMO the only way to go.
 
N4712 said:
Our boat has a polisher as result of the fuel management system, but we also have a lowest point sump.

Were I building a new boat I would spec an Alfa Laval Unit, IMO the only way to go.
Click to expand...

When you build, you'll be building to go places where it's very good to have. It certainly contributes to peace of mind.
 
I have seen far more fuel hassles from deck fill fittings than bad dock fuel.
 
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