Fuel Polishing

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Arthurc

Guru
Joined
Sep 24, 2016
Messages
752
Location
USA
Vessel Name
Sea Bear
Vessel Make
Kadey-Krogen 54
Hi,
I am about to completely redo my fuel manifold system so now is the time to redo the polishing system as well. My question is whats the best way to keep the storage tanks (350G on each side) in good condition, should each have a polishing system that runs regularly, and if so what filter and pump would you recommend. I have one polishing system already which is a higher end Racor system and plan on using it for the day tank in the middle. I was thinking that each tank with a polishing system running daily for 1 hour would ensure fuel is agitated regularly and in good condition.

Also does anyone have any experience with the P510 Racor filter? Has a pump built in which is cool but likely more expensive and harder to repair than a separate pump/filter?
https://www.racorstore.com/racor-p510mam-12-24v-multipass-fuel-polisher-with-fittings.html

Any thoughts or advice? This is an area I haven't put much time or thinking into.. yet :)

AC
 
A couple of thoughts:

Depending on your engine(s) you may already be getting a decent volume of fuel filtered just by the recirculating volume used for cooling, especially since your tankage is not so much for that vessel size. Do you know the recirc. rate for your engine(s)?

Second, whether you install more Racor filtration or not, I strongly recommend putting a large prefilter (eg Gulf Coast) before the Racors. In the event yo do pick up dirty fuel, this would take care of excessive crud before it blocks the Racors. We had no problem routinely running all fuel through a GC filter even without our (110V) fuel polishing pump operating.
 
There are lot's of opinions on polishing but I would have thought that with a day-tank there would be no need to polish.

The fuel doesn't sit around for long in the day-tank and when you refill it you are doing so with just filtered fuel. Any water or junk in the main tanks would be caught as fuel is transferred to the day-tank, normally while still in the dock or at anchor.
 
My day tank is huge so it lasts a pretty long time, and during the winter she doesn't get a ton of use so polishing may make sense...
 
I didn't see a micron specification for the P510.

While your system is more complex with more tanks, I would think a single pump and filter that can draw from any tank and return to any tank would be sufficient. For my system, I felt that a single Racor 1000 filter / separator was sufficient. That combined with around a 100 GPH pump should do a nice job and provide respectable fuel transfer speed. Then it's just a matter of picking which micron rating, 30,10, or 2.

Ted
 
The p510 has either 10 or 2 micron filters. My thinking is that each tank could benefit from a daily polish/agitation.
AC
 
It seems that "fuel polishing" discussions always err towards 2 micron or 10 micron Racor filtration. Simply put, if your fuel only has 2-10 micron particles then it is plenty clean enough. Plus the on-engine filter is always there as a back-up. IMO the real value of "fuel polishing" is not to polish at all but rather to provide a level of security in the event that you get a load of dirty fuel, or you end up with gross tank contamination usually associated with water in the tank enabling micro-organism growth, or you have really old fuel that is depositing asphaltene particles. So the real objective here should be to get rid of the crap that is significantly larger than even 50-100 microns. The way to do that is to PREFILTER with a good depth type filter before filtering through a micron-rated filter. A prefilter such as a Gulf Coast will absorb an immense amount of crap compared to any micron size Racor. While not specifically intended to remove water it will also effectively remove a significant amount of water from fuel. BTW I have no interest in GF other than as a satisfied user.
 
The p510 has either 10 or 2 micron filters. My thinking is that each tank could benefit from a daily polish/agitation.
AC
My experience is that stuff settles out to the bottom and requires serious agitation to resuspend it off the bottom. A 3 to 4' beam sea or 4'+ head sea works well for my boat. Without the agitation, I don't think polishing will have meaningful effect. In my system, fuel is taken on in one tank, and polished as it's transferred to the tank it's drawn from. Theoretically, the fuel stays clean until it's used with the possible exception of asphaltene formation. Typically I polish when in rough seas.

Ted
 
It seems that "fuel polishing" discussions always err towards 2 micron or 10 micron Racor filtration. Simply put, if your fuel only has 2-10 micron particles then it is plenty clean enough. Plus the on-engine filter is always there as a back-up. IMO the real value of "fuel polishing" is not to polish at all but rather to provide a level of security in the event that you get a load of dirty fuel, or you end up with gross tank contamination usually associated with water in the tank enabling micro-organism growth, or you have really old fuel that is depositing asphaltene particles. So the real objective here should be to get rid of the crap that is significantly larger than even 50-100 microns. The way to do that is to PREFILTER with a good depth type filter before filtering through a micron-rated filter. A prefilter such as a Gulf Coast will absorb an immense amount of crap compared to any micron size Racor. While not specifically intended to remove water it will also effectively remove a significant amount of water from fuel. BTW I have no interest in GF other than as a satisfied user.

Interesting, so I could install one on my fuel transfer system and always fill the side tanks, filling the main day tank from the sides.
 
Not sure what you are asking, Arthur. If you mean to install a filter in your fuel fill line for fuel being delivered into your side tanks, then that would be a NO. The fuel fill rate from a shore or barge pump is typically too high (20+ GPM) for any filter that would fit easily on your boat. You can install a prefilter between your side tanks and your day tank.
 
Not sure what you are asking, Arthur. If you mean to install a filter in your fuel fill line for fuel being delivered into your side tanks, then that would be a NO. The fuel fill rate from a shore or barge pump is typically too high (20+ GPM) for any filter that would fit easily on your boat. You can install a prefilter between your side tanks and your day tank.

Sorry, No, I meant install it inline with my xfer pump so the fuel is cleaned anytime it transfers tanks.
AC
 
Depending on your engine(s) you may already be getting a decent volume of fuel filtered just by the recirculating volume used for cooling.
For years I was paranoid over my fuel cleanliness. I then read an article by Tony Athens that illustrated how all the fuel that is returned from the engines to your fuel tank(s) is already filtered. Made sense to me and I shut down my frequent fuel polishing and let the engines do the work. That was about 6 years ago and I haven't had any fuel contamination since. Unless you have very large fuel tanks (i.e.: a couple thousand gallons) I think fuel polishing is "over kill!" :hide::whistling:
 
For years I was paranoid over my fuel cleanliness. I then read an article by Tony Athens that illustrated how all the fuel that is returned from the engines to your fuel tank(s) is already filtered. Made sense to me and I shut down my frequent fuel polishing and let the engines do the work. That was about 6 years ago and I haven't had any fuel contamination since. Unless you have very large fuel tanks (i.e.: a couple thousand gallons) I think fuel polishing is "over kill!" :hide::whistling:

Never polished our fuel and never found any noticeable contaminants in the crud sump built into the bottom of the tank (sample drained every 2nd month).
Never used biocide and never had a dirty filter or noticeable vacuum on gauge.

Main engine pushes 86 gallons 326 litres/hour through the racors and most goes back to the 1850 gallon 7000 litre tanks
 
I didn't see a micron specification for the P510.

While your system is more complex with more tanks, I would think a single pump and filter that can draw from any tank and return to any tank would be sufficient. For my system, I felt that a single Racor 1000 filter / separator was sufficient. That combined with around a 100 GPH pump should do a nice job and provide respectable fuel transfer speed. Then it's just a matter of picking which micron rating, 30,10, or 2.

Ted

Exactly.
No need to do more.
Use 2 Micron.
Done:dance:
 
Hi,
I am about to completely redo my fuel manifold system so now is the time to redo the polishing system as well. My question is whats the best way to keep the storage tanks (350G on each side) in good condition, should each have a polishing system that runs regularly, and if so what filter and pump would you recommend. I have one polishing system already which is a higher end Racor system and plan on using it for the day tank in the middle. I was thinking that each tank with a polishing system running daily for 1 hour would ensure fuel is agitated regularly and in good condition.

AC

I just re-did my fuel system plumping on my trawler. Originally it was equipped with Racor 500's (one per engine and gen). I replace them with Racor 900's 10 micron, same configuration one per engine and left the 500 @ 10 micron for the gen set alone. I got brand new twin set of 500's @ 30 micron and plumb them in to a new manifold powered by 12 volt Marco fuel transfer pump. Important do not overpower your filters! If your filters flow capacity is 160 GPH do not use 200 GPH pump. You will collapse the filters. The other hint I got from pro's is if you really want to clean you fuel effectively I add an extension to each of my four tanks drain valve's to connect small air compressor. By blowing ( not allot of pressure just enough to bubble other wise open you filling port then you can blast ) the air in, it lifts all sludge from the bottom. Creates better suction and much better result. I hope this will help you. Good luck.
 
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On my AT (400 gal fuel) I had an Reverso 12vt 80GPH fuel polishing system installed. It is installed so as to draw from either tank and sent to either tank. (Also, draw from both makes and returned to both tanks, my default.) I believe it is on a 7 day scheduled timer or manual on-demand timer defaulting to 5 hours.
For the 80 GPH model, it has a proprietor filter, this is the only part I do not like. The filters come in 10micron or 30micron or 50micron sizes.
After a initial run of more than 20 hour run on a 30micron filter, I changed to a 10micron filter for the long run.
Per when to filter, I like dock side filtering although, I can draw and return from one tank while underway. Underway, the installed dual Racor1000 does a mighty fine job.
 
True fuel polishing is done with high pressure and high volume (600 to 1000 gallons per hour and up) gear pumps. Without the volume and pressure, there is not enough agitation to remove contaminants stuck to the tank wall and at the bottom of the tank below the fuel pick up.

Without cleaning the tank sides, the contaminants will reappear.

To clean the tank thoroughly, openings are required to access the interior of the tank. A spray wand is used to spray diesel onto the tank walls at pressure to remove stuck contaminants. Sometimes brushes and plastic scrapers are required to dislodge stubborn contaminants. The contaminants washed off are directed to the fuel pick up point to be filtered and recycled back to the spray wand.

In severe cases, the contaminated fuel is pumped into drums to be cleaned before returning to the cleaned tank.

Once the tank interior is completely clean, biocides and periodically recirculating the fuel through filters with a lower volume pump will keep the fuel clean.

I inspect my two 300 gallon fuel tanks by opening the inspection ports every 10 years. If contaminated, I use a portable gear pump with two Racor 1000's in parallel to clean the tanks with a wand.

I have a small 80 GPH pump permanently installed to circulate the fuel through the engine Racors and back to the tank. My tanks are bottom feeders from a sump so the filters picks up all water and debris.

I test for water in the tank with Kolor Kut and run the circulation pump monthly.
 
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Short of cleaning up a load of bad fuel, or a tank fouled by long term neglect, I don't think there is a lot of value in on-going polishing. As others have noted, polishing is continuous when running the engine and I have never seen any significant accumulation of crud.


Personally I like the arrangement of a transfer pump and filter that can also be used to clean up a mess, should you get one.
 
Short of cleaning up a load of bad fuel, or a tank fouled by long term neglect, I don't think there is a lot of value in on-going polishing. As others have noted, polishing is continuous when running the engine and I have never seen any significant accumulation of crud.


That does'nt apply to us Ford Lehman 120 owners. The engine returns very little fuel back to the tank while running.
 
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