Installing a fuel polishing system

[Stu Jackson]

Originally Posted by DeepFrz

Stu, I don't think Vancouver Island is any worse place for bio growth in fuel tanks than other places where it rains a lot but you have to be careful. As has been mentioned several times at least in this thread the engine fuel pickup does not reach to the bottom of the tank. Any water that gets into the tank will stay there and cause problems. One just has to be very careful. Fueling in the rain can put water in the tank and depending on where and how you sail that may be an inevitable thing. Anyway that's about all I can think of. Good luck and enjoy your new environs. I loved Van. Isl. but had to leave the area for a number of reasons.

Thanks for coming back on this. I'll be careful and keep my eyes peeled more than I used to do.

[kmacdonald]

If the diesel is old enough to create sediment and gum it is no longer good and should be discarded. If you "polish" it you will have clean bad diesel. Having a filter between the tank and engine "polishes" the fuel before entering the engine. A fuel "polishing" system does not enhance the process. Diesel is good for about 18 months in cold climates and only 6 months in hot climates. "Polishing" diesel doesn't do anything to prevent diesel from going bad. Don't be "polished" by old wives tales.

[Littlechay]

Originally Posted by Kenomac

And so it continues..... but now on a different thread.

Is that a self portrait?

[Panope]

Stu, Not to discount DeepFrz's comments, but here is a local data point.

Panope has:

-Had fuel in her tank(s) continuously for 37 years,
-Tanks that have NEVER been full.
-Sometimes been stored on the hard, once for more than a decade.
-Had one load of fuel sit unused for 12 years.
-Had a total engine running time appx 5000 hrs.


Results:

-I have never found ANY foreign material in the fuel filters or tanks.
-I once found a couple DROPS of water in a sump. (fuel pick-up is at the EXTREME low-point of tank - no water is hiding in the tank)

Perhaps I am not only a fool (black hull), but a lucky fool to boot!

Steve

[captain58sailin]

Here are some shots of my fuel system, I used a Diesel Craft centrifuge, and converted my racors into a dual system, 3 way valves and a vacuum gauge. I've now have enough time on the unit to report my performance. Since May, I have been operating almost continuously and ran approximately 2000 usg through the system. On the initial start the fuel in the tanks was several years old, I added new fuel and Power service additive to all the tanks, as well as ActiveX. I had to add a larger electric fuel pump as the engines starved for fuel when I put the blast freezer online. In the early running, I experienced a clog of the centrifuge as I had not drained it since the start up, it plugged completely and I had to run a zip tie up the drain to knock the sludge loose. After that I drained a small amount of fuel off every other day to prevent this from reoccurring. I then ran the vessel all over, never once needed to change a racor or engine filter. When I arrived in Sitka, AK from Homer, AK approx 560 nm across the gulf of Alaska, I did change the engine filters and the racor, although there was no indication it was needed. I am using 10 micron racors, my vacuum gauge never came off of zero. There was some sludge in the main engine secondary filter housing, but not enough to affect performance. Coming across the gulf of AK we experienced large enough seas to thoroughly stir things up. After Sitka, we made for 200 nm offshore and made our way south trolling for Tuna, we experienced no fuel related problems and adhered to our draining a small amount from the centrifuge every other day. I realize my system is a larger capacity than most here would find usable, I just wanted to report on something that worked for me. I just put the vessel on the hard, and we were still running on the same filters we left Sitka on and we rode out several hard blows offshore, so there can be no doubt about the fuel getting stirred up.

[Dockhead]

Originally Posted by kmacdonald

If the diesel is old enough to create sediment and gum it is no longer good and should be discarded. If you "polish" it you will have clean bad diesel. Having a filter between the tank and engine "polishes" the fuel before entering the engine. A fuel "polishing" system does not enhance the process. Diesel is good for about 18 months in cold climates and only 6 months in hot climates. "Polishing" diesel doesn't do anything to prevent diesel from going bad. Don't be "polished" by old wives tales.

Where did you get that idea? Polishing fuel is specifically recommended by BP and others:

http://www.bp.com/content/dam/bp-cou...age-diesel.pdf

Fuel polishing most definitely does take a load off the main engine filtration system and may catch problems before they can overwhelm the main engine filtration system and stop the engine.

Fuel which is "old enough to create sediment and gum" is one hour old. Diesel fuel oxidizes and throws sediment. It's what it does. It's a continuous process.

[Dockhead]

Originally Posted by captain58sailin

Here are some shots of my fuel system, I used a Diesel Craft centrifuge, and converted my racors into a dual system, 3 way valves and a vacuum gauge. I've now have enough time on the unit to report my performance. Since May, I have been operating almost continuously and ran approximately 2000 usg through the system. On the initial start the fuel in the tanks was several years old, I added new fuel and Power service additive to all the tanks, as well as ActiveX. I had to add a larger electric fuel pump as the engines starved for fuel when I put the blast freezer online. In the early running, I experienced a clog of the centrifuge as I had not drained it since the start up, it plugged completely and I had to run a zip tie up the drain to knock the sludge loose. After that I drained a small amount of fuel off every other day to prevent this from reoccurring. I then ran the vessel all over, never once needed to change a racor or engine filter. When I arrived in Sitka, AK from Homer, AK approx 560 nm across the gulf of Alaska, I did change the engine filters and the racor, although there was no indication it was needed. I am using 10 micron racors, my vacuum gauge never came off of zero. There was some sludge in the main engine secondary filter housing, but not enough to affect performance. Coming across the gulf of AK we experienced large enough seas to thoroughly stir things up. After Sitka, we made for 200 nm offshore and made our way south trolling for Tuna, we experienced no fuel related problems and adhered to our draining a small amount from the centrifuge every other day. I realize my system is a larger capacity than most here would find usable, I just wanted to report on something that worked for me. I just put the vessel on the hard, and we were still running on the same filters we left Sitka on and we rode out several hard blows offshore, so there can be no doubt about the fuel getting stirred up.

That's a pretty cool system!

Where did you get the fuel centrifuge?

Seeing your larger Racors made me think -- for those of us who have room for them, is there any downside? Does the fuel need to flow at any particular velocity in order for the swirling water separator thingie to work?

The bigger filters will be able to catch more crud before clogging -- might be a sensible precaution.

Theoretical question for me (knock on wood!) as I've never had fuel problems on my present boat. I have the tanks opened up and cleaned out every two years, and I've been lucky not to have had to buy fuel at any dodgy places. Also, I think diesel fuel is more stable in cooler climates like up here.

[DeepFrz]

Boats and ships are not the only things that polish fuel. Most commercial fuel polishing outfits make their money taking care of emergency commercial fuel systems. I would guess that most of these organizations store the fuel for years until some emergency situation forces them to use it.

[Matt Johnson]

Originally Posted by Dockhead

That's a pretty cool system!

Where did you get the fuel centrifuge?

Seeing your larger Racors made me think -- for those of us who have room for them, is there any downside? Does the fuel need to flow at any particular velocity in order for the swirling water separator thingie to work?

Yes. Check Parker's site for info on needed flow for their filters water separating feature.

Matt

[kmacdonald]

Originally Posted by Dockhead

Where did you get that idea? Polishing fuel is specifically recommended by BP and others:

http://www.bp.com/content/dam/bp-cou...age-diesel.pdf

Fuel polishing most definitely does take a load off the main engine filtration system and may catch problems before they can overwhelm the main engine filtration system and stop the engine.

Fuel which is "old enough to create sediment and gum" is one hour old. Diesel fuel oxidizes and throws sediment. It's what it does. It's a continuous process.

You should reread your own link. It says:
Under normal storage conditions diesel fuel can be expected to stay in a useable condition
for:
• 12 months or longer at an ambient of 20ºC.
• 6-12 months at an ambient temperature higher than 30ºC.

I don't know how it could be any clearer than that.

[Dockhead]

Originally Posted by kmacdonald

You should reread your own link. It says:
Under normal storage conditions diesel fuel can be expected to stay in a useable condition
for:
• 12 months or longer at an ambient of 20ºC.
• 6-12 months at an ambient temperature higher than 30ºC.

I don't know how it could be any clearer than that.

That was not what I was challenging. You said that fuel polishing is useless. It certainly is not. British Petroleum say this about it:

"Establish a system for filtering the contents of the main storage tank through a recirculating filter system. This can be made automatic and will reduce the potential for problems by removing sediment and gums. The filters should be checked and changed at regular intervals. When the filter change interval reaches a certain frequency then the fuel should be changed over. "

From the link referred to.

The point is that diesel fuel doesn't sit there in perfect condition for 6 to 18 months and then just one day turns bad and starts throwing sediment. It oxidizes continuously, so it is worth while cleaning from day 1.

Fuel polishing is best practice, and many long distance cruising and expedition boats have such a system.

The best one I've seen is on Jedi, a Sundeer 64, described in detail in another thread here. But Ken's is also very nice.

[weavis]

NOt to knock the years of experience people have with diesels in whatever capacity of being country boys an awl, and not to step in as an expert here coz in the USA i was a big offshore 40 foot petrol user.. However, here is Seville and back in the UK, my buddies who run diesel operations SWEAR by fuel polishers.

It seemed to me that J who had twin diesels, for nearly 15 years had fuel issues. He had his tank cleaned a few years ago and did it again a couple of years later. In 2009, he invested in a polishing system and never had an issue since.

Here on the river in Seville, after a bad batch of diesel and a huge cleanup of the tank and system, another friend put a polishing system aboard. He runs his unit all day as a passenger /restaurant service and the engine and generator runs all his essential services so cannot afford to entertain bad fuel. He has had no problems since.

For those that have no trouble and 30 years trouble free diesel operation, that is great. It is not the norm though. So much so that once a person has an issue it seems to hang around despite filters and unclogging pipes and removing sludge etc.

YOu may consider it an expensive "add on" to a boat. I see Diesel as the source of a lot of problems depending on how its processed. Its not 'clean'.

Polishing fuel DAILY keeps everything clean. Its not a huge drain on power and not ever a waste of energy. It would solve all of a64 issues simply because it negates the requirement for all the filters to work so hard by only having a clean source of fuel to important parts.

TO me its a no brainer. Logical and cheap to run and something most of the commercial diesel operations use. YOu just cant trust diesel fuel in some places... I wouldnt risk it.

[Stu Jackson]

Thanks, Steve. Between you and DeepFrz I have some good learning points.

Originally Posted by Panope

Stu, Not to discount DeepFrz's comments, but here is a local data point.

Panope has:

-Had fuel in her tank(s) continuously for 37 years,
-Tanks that have NEVER been full.
-Sometimes been stored on the hard, once for more than a decade.
-Had one load of fuel sit unused for 12 years.
-Had a total engine running time appx 5000 hrs.


Results:

-I have never found ANY foreign material in the fuel filters or tanks.
-I once found a couple DROPS of water in a sump. (fuel pick-up is at the EXTREME low-point of tank - no water is hiding in the tank)

Perhaps I am not only a fool (black hull), but a lucky fool to boot!

Steve

[kmacdonald]

Originally Posted by Dockhead

That was not what I was challenging. You said that fuel polishing is useless. It certainly is not. British Petroleum say this about it:

"Establish a system for filtering the contents of the main storage tank through a recirculating filter system. This can be made automatic and will reduce the potential for problems by removing sediment and gums. The filters should be checked and changed at regular intervals. When the filter change interval reaches a certain frequency then the fuel should be changed over. "

From the link referred to.

The point is that diesel fuel doesn't sit there in perfect condition for 6 to 18 months and then just one day turns bad and starts throwing sediment. It oxidizes continuously, so it is worth while cleaning from day 1.

Fuel polishing is best practice, and many long distance cruising and expedition boats have such a system.


The best one I've seen is on Jedi, a Sundeer 64, described in detail in another thread here. But Ken's is also very nice.

I never said it was useless. Please get your facts straight or stop making wild and unfounded accusations. I said it wasn't necessary.
As you can see from your bolded quote above, BP says the fuel should be changed over, meaning discarded as bad, when the filters clog at an excessive rate IMHO.
The simple solution is a fuel management system that uses fuel before its minimum useful life has been reached. Polishing fuel is like chasing your tail. I just love the stories where people get their tanks "professionally polished" only to have the problem return in short order. Then they spring for a tank cleaning. If the old fuel is discarded, problem solved, if not the process continues.
I don't know of any Maine lobster boats using "fuel polishing systems" and they don't have problems with fuel. No one does that use their boats often and replace the o-ring on the fuel fill once in a while. Trucks don't "polish" their fuel because they use it before it goes bad. Try to connect the dots, it's really not that hard to do.

[weavis]

Originally Posted by kmacdonald

You should reread your own link. It says:
Under normal storage conditions diesel fuel can be expected to stay in a useable condition
for:
• 12 months or longer at an ambient of 20ºC.
• 6-12 months at an ambient temperature higher than 30ºC.

I don't know how it could be any clearer than that.

I tell you what can be clearer. It could be you in a diesel powered vessel 40 miles offshore with dirty fuel in a seaway that is throwing you all over the place, stirring the tank and your 8 month old useable fuel has water and chunks in it.

'Useable' refers to the whether diesel is able to be used, it does not refer to problems encountered with water and contaminants. Its clear that engines have masses of filtration to prevent 'useable' fuel from becoming unusable.

Diesel trains regularly have issues with fuel. SO much so that after taking on board about 10000 gallons of diesel for the long haulers, this particular unit has four external polishers, 2 at each end of the train, running at stops and services. These units pump at 80 gallons a minute which clean the main tank into the supply tanks. Their issues stopped after this.