fuel polishing

[jim]

What does anyone think of fuel polishing?
Is it really worth the effort ( money) and could it actually cause more problems? ie holes in the fuel tank.
Thanks for any comments
Ohana is on the HARD right now and it might be a good time to have it done.
Jim

[Randy]

Jim,

I polish the fuel in Ventures tank each year. I simply bought a relatively inexpensive 12 V pump and attached a water seperating fuel filter to it. I remove the fuel gauge sending unit from the top of the fuel tank and install one end of the hose from the 12 V pump.  The other end of the hose goes into the deck fuel fill. Turn the pump on and circulate fuel from the tank through the filter and then back into the deck fill. Let pump run about 30 minutes and you will have polished all 50 +/- gallons removing all the water and sediment. Hope this helps.
Randy

[captsandy]

  To really polish the tank and fuel you have to aggitate the tank also. A professional will use a small hose under high pressure to return the fuel to the tank. The hose flops around like a snake and breaks loose as much sediment and scale as possible. This is the stuf that will break loose when you are sailing or motoring and the fuel is sloshing around in the tank. There are additives that can loosen disolve these also. StarTron is the best cleaner. Also use a additive every time you add fuel and you shouldent have to polish your fuel unless it sits in the tank for more than a year.
     S

[EdHouston]

Is it not true that your polishing your fuel whenever your running your engine, its my understanding that the engine only uses a portion of the fuel being pumped to it, the remainder is being returned to the tank, this fuel should be going through you filters and hence polishing it!

Chime in and let me know if I am wrong here!

Ed

S/V Moonlight Mile #110

[jim]

I agree that running your engine is a form of polishing, but we try to sail as much as possible. It seems hard to polish all the fuel in the tank.
I use an additive every time I add fuel. The part that concerns me is the what is in the bottom of the tank.
Jim

[EdHouston]

I am planning on using my Moeller pump to draw off any water or crud from the tank bottom, haven't tried this yet but it's on the list. My tank was replaced by the previous owner maybe four or five years ago so I am assuming the crud level should be negligible I always use a fuel additive when putting fuel on board. My Racor stays clean and shows no sign of fouling; I have a very simple logic if its not broken don't fix it!

Any crud water whatever is going to be at the bottom or lowest part of the tank (at the dock), the fuel pick up is off the bottom at least an inch so, as long as the crud is below the pickup then unless we are pounding rough seas it should not get into the pickup if it does then the Racor will catch it.

Having said all that if your Racor is showing excessive amounts of crud then you may have a problem that needs immediate attention "polishing".

Good luck remember "an ounce of prevention is worth a pound of cure"

Ed
S/V Moonlight Mile #110

[Scott]

Sorry for a bit of a hijack here, but I am curious about people's levels of crud in the racor.  After about 150 hours my filter has a noticeable bit of brown "dust" that comes off of it when I change it.  I am using a racor 500 series 3 micron filter.  I have also previously found a bit of crud in the clear bowl, but since last cleaning it out that hasn't returned.  I have been cruising for about 500 hours on the engine over the last 7 months and have definately been in seas that have agitated the fuel significantly.  I have been considering polishing the fuel, but haven't yet found a place to do it.  Is this level of contamination unusual?
Thanks! 

[Jim Cozy]

Last summer we had the fuel polished at the beginning of a three week cruise. Subsequently, the engine quit three times due to a clogged Raycor. My guess is that the polishing job was inadequate due to a lack of high-pressure backwash to loosen crud, although some was obviously loosened and not removed. Since then I pulled a sample from the tank bottom which was relatively clean. I still believe in polishing, but unless the tank is agitated I think the job will be incomplete. The very best solution is to use enough fuel to keep recirculating new fuel but with a 50 gal tank and annual usage of about 20 gal this is unlikely. Scott, from your description, you sound like you are in good shape and I would not worry too much about it.
As an aside, I had mounted a vacuum gauge on the Raycor, but it gave me no warning of impending clogging, but it may have been leaking a little air. I tightened it but with our six-month season, have not been able to check it out. If I learn more , I will post it.

[Scott]

Thanks Jim!  I had no clue how much was "too much."  The boat was from up north, so I didn't expect to have any problems but you never know....

[gazuum]

 My neighbor does fuel polishing professionally and one of the big problems he sees is boaters using too fine a filter. After all, if 10 micron is good, 2 micron MUST be better!
  Not so! Use the filter recommended for your engine.
  He polishes down to 10 microns and if you check around, you'll find most commercial boats run 30 micron filters.
  As for how often, most boats he does are from the 70's and early 80's and have never been polished and definitely need it. Once done, it should be good for years. Of course, there was the power boater that put fresh water in his fuel tank two weeks in a row!

[Puffin]

I have had a good deal of experience with dirty diesel tanks and fuel polishing.  I will be addressing this issue again in the 365 we just aquired.  We also own and cruise a trawler with two 350 gallon fuel tanks.  Those tanks had not been cleaned in 20  years and had sat unused for the two years prior to our purchasing her.  We had to move her several hundred miles in open water soon after the purchase.  The first thing I did was rig an onboard fuel polishing system with two filters and a 20 gal. day tank.  I polished fuel from the large fuel tanks, diverted clean fuel to the day tank and ran the engine off the day tank.  We did a lot of filter changing but were able to keep the engine running.  When we reached her new port we had the tanks "professional polished" by two different companies.  There efforts were helpful but not effective enough to be able to operate the vessel in rough seas.  The solution was to install three inspection ports in each tank and use a high pressure pump to "wash" each area that was separated by baffels in the tank, drain the tank, and clean by hand the sludge that washed to the bottom of the tank.  I did this with less than a half load of fuel so that I could pump all the fuel to one tank while I cleaned the other.  I did this for both tanks and then ran the fuel polisher for several  weeks pumping fuel back and forth between the tanks.  I also run the fuel polisher whenever the engine is running.  This battle was over a two year period.   Once I decided to open the tanks and clean them we were able to beat the problem.  We ran to Alaska and back without fuel issues.  I use 4 micron  filters for polishing and 10 micron on the engine.  My four micron filters are located in such a way as to be able to change them in relative comfort and ease.  The 10 micron are on the engine and are my last line of defense to protect my injecters.  They are also more dificult to change.  I like to keep them in good enough shape that I only change them at my time and place of chosing.