Fuel Polishing

Dec 19, 2006
5,809
Hunter 36 Punta Gorda
I had fuel problems and so I have a extra Racor 500 and electric fuel pump and want to add a fuel polishing system on my 2007 H-36.
I have plenty room and want to add into my already fuel system.
How did you install your system and how do you work it.
Nick
 
May 20, 2016
3,014
Catalina 36 MK1 94 Everett, WA
I installed dual racors with on-off at entrance to each then lift pumps for each then “3-way” valves for each with output going to engine or back to tank. Electricity for each pump goes to an on-off-on toggle for each pump. One on goes to switched power and one goes to power.

You can polish with either or both or feed the engine with either; or it can sit and do nothing. I can switch fuel filters in the time it takes to flip 4 valves and two switches ( under 30 seconds).

Les
 
May 24, 2004
7,129
CC 30 South Florida
Nick it is not worth it to fabricate your own fuel polishing system unless you intend to go commercial. It is not something that will be frequently used and fabricating a fuel system with the needed high capacity components is not cheap. If needed it is best to pay a professional to come out with his equipment and polish the fuel. A 2nd Racor filter can hardly be called a fuel polisher. Our 2001 h320 had the tank cleaned and the fuel polished in 2016 for the first time. We had a glob like you did which was mostly extracted by the power of the high flow pump and hoses of a commercial fuel polishing system. For redundancy you could carry a spare electric fuel pump. I'm happy with the mechanical lift pump and simple connections. If the engine quits we sail in or call TowBoat US.
 
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Oct 10, 2011
619
Tartan 34C Toms River, New Jersey
I agree with Benny. Although I have a OLD gas motor, most of my friends have diesel and just use a fuel additive. No one has an fuel problems.
The thing is I use very little fuel during the season as I motor out of the channel which is a few hundred yards and let the wind take over.
I have used a total of six gallons, which means my fuel sits in the tank for a long period of time. The additive I use seems to keep the fuel clean. I replaced the tank seven years ago, when I refurnished the boat (she is a bit if a dinosaur).
I'll be honest I am not familiar with fuel polishing!
 
Oct 22, 2014
20,995
CAL 35 Cruiser #21 moored EVERETT WA
she is a bit if a dinosaur
Careful. Loose lips sinks ships. She (your Tartan 34 is a female) is always listening and being called a dinosaur might be considered derogatory. You may pay a price for that.

Fuel polishing is a fancy word for filtering your fuel in your tank. With diesel it is removing water, biologicals, and contaminants that can occur in fuel stored in a tank over time.

There is a science to all this, but the basics is to reduce the contamination so the the fuel flows and can be consumed in the engine to move your boat through the water. Clogging the fuel injectors with goo will stop your engine, especially these modern engines.
 
Dec 19, 2006
5,809
Hunter 36 Punta Gorda
Basically that is what I thinking of doing is running the unused fuel in my tank
through a separate racor filter, use the pickup tube in tank to suck out fuel from tank
back into return tube into tank.
 
May 20, 2016
3,014
Catalina 36 MK1 94 Everett, WA
I agree it's not worth it to have just for polishing, but add in a ready spare for both lift pump and clogged filter - to me its worth it. The filters are hard enough to change/get to, I suspect if they plug it will be in severe chop, mixing up and unsettled bottom. I know @jssailem is a master and quick changing his Racor, but I can beat his time easily - without a drop of diesel in the boat or air in the lines.

Les
 
Dec 19, 2006
5,809
Hunter 36 Punta Gorda
A friend said what he does a bout once a year sticks a tube into his fuel tank down to bottom of tank and uses a oil changer to suck out anything like water or dirt out the bottom.
Don’t know if that does any real good.
Nick
 

Tom J

.
Sep 30, 2008
2,301
Catalina 310 Quincy, MA
I think that, technically, "polishing" should refer to a specific process by which the fuel is reconditioned to a like-new condition, and the tank is cleaned of as many contaminants as possible. I was very impressed with the mobile setup of the gentleman I hired to polish my fuel a few years ago. He removed the access plate on the fuel tank, placed a suction hose to the bottom of the tank, and inserted a return hose. His cart was equipped with multiple filters and sensors to detect contaminants. He let the fuel recycle repeatedly, until he was satisfied the fuel and the tank were clean.
I have been at marinas where a pump was attached to the existing fuel lines, and the fuel was passed through a filter. I would call this "cleaning" the fuel, as opposed to actual polishing.
I have been on several boats, including my own, where the engine has died due to the filter being clogged. This almost always happens at the worst possible time, because usually conditions are rough, which has stirred up the contaminants, and it would be very difficult to change the filter. Yes, I have been able to continue sailing, and change the filter later, but can you imagine being off a lee shore and trying to claw your way to safety? For this reason, I think having a spare filter in the system, available for immediate use, is well worth the effort and money to install.
 
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Jul 23, 2009
857
Beneteau 31 Oceanis Grand Lake, Oklahoma
If you can reach the bottom of your tank with a suction tube and pump the trash/water off of the bottom do it.

I have to pump the water, slime and rust out of several diesel generators that I maintain. It does wonders to prevent clogged filters later in the year. I also use a commercial fuel polishing rig every 5 - 10 years on the large units.

Fuel polishing is just repeatedly filtering the fuel through a water separator and fine filters. The beauty of a high volume unit is that it stirs up the trash at the bottom and knocks it loose from the tank walls.
 
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Mar 20, 2004
1,729
Hunter 356 and 216 Portland, ME
My 29.5 had a really dirty tank and she continually died entering the Merrimac river to head for our mooring - so I built a fuel polishing system with a racor and a transfer pump mounted in a 5 gallon pail - worked well, so I keep it around and periodically clean Escape's tank if I see signs of an issue, However, I use Biobor and like Leslie, I have dual racors with independent pickups on Escape as well as a reserve electric fuel pump.
 
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Oct 10, 2011
619
Tartan 34C Toms River, New Jersey
Why all the fuel problems here? I ran a 31 Bertram out of Manasquan inlet to the Hudson Canyon for years and never had a bad fuel problem, not saying there were other problems encountered!(guess we used a lot of fuel)
We had a regular service plan that changed/cleaned the filters on a specific schedule. Believe me we beat the hell out of that boat on our trips.
 
Feb 6, 1998
11,667
Canadian Sailcraft 36T Casco Bay, ME
Guys,

Fuel polishing, the come to your boat with large equipment type, is really a big waste of money on a sailboat with small tankage. For a power boat with 300+ gallons it may be your only option but on a sailboat with sub 40 gallon tank I will chalk it up to a quasi scam level service.

You can DIY this job better than a professional can. Let the fuel level drop, over a period of time, suck the rest into 5 gal cans and dispose of somewhere that burns #2 oil in a furnace, boiler etc.. We're talking a few dollars worth of old fuel here.

Now spend the time and money to get in there and physically & manually scrub the tank walls. The money you save in professional polishing will pay for some excellent clean out/access ports such as those made by Seabuilt. You'll need one for each chamber in the tank. Unlike a one-time service, that really only gets the fuel in the tank clean, these access ports can be used numerous times over the life of the boat.

I have yet to see any professional "polishing" job that gets the inside of the tank "clean", not one, and I have seen a LOT of boats after they have been "professionally polished". Once you've done this job, you'll quickly see why it can't actually get the tank clean only the fuel and most of the free floating debris. The stuff is essentially like tar and no amount of pressure can reach all areas of the tank, due to baffles, or get the tank walls physically clean.

Once your tank is physically clean there is no reason not to install an on-board polishing system that, from this point onward, helps keep the tank clean and spotless.

I did this on our own boat back in 2006 and the tank walls to this day are still 100% spotless & shiny with not even a hint of discoloration. I work on far newer boats, more recently built, where the tank walls are already filthy and fuel related issues are already rearing their ugly heads.

To say that an on-board re-circulation/polishing system can't work, I can only surmise, is simply a clear lack of experience with such a system. Personally, I will never again own a vessel that runs on diesel without also having an on-board polishing system. Our re-circ system filters down to 2 micron, turns the tank twice per hour, and is completely separate from the engine system. Our fuel is always crystal clear with no-haze. The re-circ runs whenever the engine does or can be flipped on at any time even without the engine running.

Perhaps the biggest culprit I see when it comes to diesel issues is lack of o-ring maintenance on the fill cap. Ours gets replaced about every fourth fill up because it is dirt cheap and takes all of 4 seconds. Very cheap insurance. I simply located the correct size O-ring then ordered 100 of them for about $8.00.
 
Mar 26, 2011
3,401
Corsair F-24 MK I Deale, MD
^^ Everything he said.

I am a licensed API tank inspector, and I have been in many tanks that had been "cleaned" by polishing contractors. I'm not sayin' they didn't remove some water and suspended dirt, but they didn't get to the bottom. Important, from my point of view, is that serious corrosion nearly always occurs UNDER hard deposits that can only be removed mechanically. It is the hard sludge that creates the conditions required for serious galvanic corrosion (not dissimilar metals, in general, but the micro-environment under the sludge is sufficiently different to start a battery.

I don't considered being towed in to be a plan. Doesn't work everywhere, doesn't work in bad weather, and doesn't work well at night. I've never been towed in 40 years.
 
Jun 1, 2007
265
O'Day 322 Mt.Sinai
FWIW, here's what I did with my O'Day 322 w/Yanmar 2GM20F. I bought a 12V fuel pump, and placed it after my Racor fuel filter (I run with 2 micron here. If there's a problem, I want it stopped at the primary). I then bought 2 3-way valves and some fuel line, and added an engine by-pass circuit. I can now set the valves to by-pass, turn on the fuel pump, and run tank diesel through the Racor and back to the tank to polish. I do this from time to time. I can also use the electric fuel pump as a backup to the engine driven pump. In addition, I can drain my fuel tank with the electric pump (which I just did).
I also just bought a Seabuilt 6" inspection port. Now that my fuel is mostly drained, I'm cutting an 8" hole in the top of the tank, draining every last bit of fuel, and then wiping that tank nice and clean, then installing the inspection port (8" hole ends up with 6" port opening). From here on out, I should be good to go as Maine Sail said earlier.
 
Dec 19, 2006
5,809
Hunter 36 Punta Gorda
I did pump out every drop of fuel out of my tank and than used shop vac to suck out the bad globe
laying in bottom and now tank so clean and will add new O ring on fuel tank cap.
It was 2007 since ever having any fuel problems so not too bad,never had a fuel problem before ever.
Nick
 
Oct 22, 2014
20,995
CAL 35 Cruiser #21 moored EVERETT WA
I’ve resisted cutting holes in my tank and getting oily up to my elbows for a couple of reasons.
  1. Fear of what I may discover.
  2. Another hole is a place for a leak
  3. More holes more diesel perfume smell opportunities
  4. Chemical additives, fresh fuel, replacement of fuel cap O rings, a fuel filtering (polishing type project) and filter changes appear to have addressed the problem.
I was about to buy a high volume fuel pump and a couple large filter units on a hand truck in 2016. I decided against the plan for a couple of reasons.
  1. Concerns about putting air into the stored fuel (foaming).
  2. Static charge build up in fuel lines from high flow through pvc pipes/hoses.
  3. Effectiveness of a copper spray wand to dislodge fuel sludge in the tanks.
  4. The problem of spill containment and liability.
The inline multiple Racor filters do not have that problem. They are not as robust as a high speed pump cart system but they serve to provide redundancy and immediate change over for a dirty fuel filter blockage problem. This may be enough to keep you safe in most conditions.
 
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