Home built fuel polisher

PabloPicasso

PabloPicasso

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Ok so on a recent thread fuel polishing came up. Who's built a home made system. Doesit recirculate or decant into a container? What diameter are the sucking end and pipes, are they permanently fitted? Are the systems a success, would you modify them if you built them again, etc,etc?
 
I don't really see the point with my engine (Volvo 2003). When it's running, the return to the tank is a clearly audible trickle, so far more fuel is being circulated through the water trap and engine filters than is being burnt! I reckon that the diesel in the tank is probably turned over fairly quickly while running the engine - it must return at least a litre a minute, judging by the noise, so a full tank would be circulated in a couple of hours running. So, my fuel is being routinely cleaned by running the engine, without further equipment that would only do the exact same thing.
 
PabloPicasso said:
Ok so on a recent thread fuel polishing came up. Who's built a home made system. Doesit recirculate or decant into a container? What diameter are the sucking end and pipes, are they permanently fitted? Are the systems a success, would you modify them if you built them again, etc,etc?
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littleship is your man for this.
 
mine is work in progress but currently draws from one saddle tank and pumps into the other ( the active one). previously I could only do this by gravity. The intake pipe is near the bottom of the tank so I have the option ( By switching pipes around) to decant into a separate container and if it still looks mucky to switch more pipes and have several passes of the mucky stuff.
Normal practice has been to use the container only now and again ( start of season or after a shake up) then just use the system from tank to tank. I can get a fair idea of the clarity by inspection of the fuel passing through the clear pipes or in the glass bowl.
Mine is just a simple system, I don't need to use it at sea and all I need to do is just tidy the existing system up a bit.
I think you need to start with a clear idea of what you want to achieve.
 
Mine is explained and pictured here.

http://turbo36.wordpress.com/improvements/

The filter from eBay is 110489697848 now £45. I found a secondhand 12 v pump for about £15

The instant drip less connectors are great. I can suck from and return to either tank, plus I can clear the main pickup and prime the pre filters

I run it on each tank for about 1-2 hours. I don't worry about condensation with part full tanks, and run between 1/4 and 1/2 tanks, which keeps boat weight down.
 
+1
If you want to see for yourself, lead the return line to a separate container and run the engine..

AntarcticPilot said:
I don't really see the point with my engine (Volvo 2003). When it's running, the return to the tank is a clearly audible trickle, so far more fuel is being circulated through the water trap and engine filters than is being burnt! I reckon that the diesel in the tank is probably turned over fairly quickly while running the engine - it must return at least a litre a minute, judging by the noise, so a full tank would be circulated in a couple of hours running. So, my fuel is being routinely cleaned by running the engine, without further equipment that would only do the exact same thing.
Click to expand...
 
Hmmm I had not realised this. I guess this is the overflow as the fuel pump must deliver greater pressure than needed to maintain the integrity of the fuel delivery. Good to know though

So why the fuelpolishing 'industry'?
 
PabloPicasso said:
Hmmm I had not realised this. I guess this is the overflow as the fuel pump must deliver greater pressure than needed to maintain the integrity of the fuel delivery. Good to know though

So why the fuelpolishing 'industry'?
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Polishing the fuel on a regular basis sounds unnecessary.
But if you have been so unlucky that your tank contains large volumes of contamination, polishing is a better option than replacing the ordinary fuel filter + bleeding the system at frequent intervals.

If you check the fuel filter regularly and pump out a sample from the lowest point of the tank once a year you should be safe.
 
I also don't understand the point unless you have had a disaster. Fuel polishing appears to be running fuel through a filter. My engine has a filter which the fuel already goes through. I carry spares. It has a water trap. Why the need for the duplication? If concerned, say at beginning of season, run the engine for a few hours and then change the filters.

P.s. the way I set up my filters changing them and bleeding only takes a moment and certainly less time than it would take messing around with a DIY fuel polishing kit.
 
I have a pump and filter set up on a board , just to enable me to pump from jerry cans on deck and filter the contents before entering the tank, it also enables me to move fuel out of one tank and into the other to enable cleaning of the empty tank.

It does have its uses , just depends how old your boat is - mines ancient and the tanks steel so common to need a clean up after rough weather, its a pain in the ass but easier to do that every once in a while than spinning off filters in rough seas on the entrance to a harbour or something .
 
I've had the bug twice. Built a simple system that draws off the tank drain point, seperator filter, electric pump and tees into the return to the tank from the regular fuel line. All 8mm copper or fuel hose. Electric pump runs whenever engine breaker is on.

Have not had a bug regrowth in two seasons but maybe I'm just more carefull with soltron and clean fuel from road stations. Did however fill nearly 200l from a marina bowser last trip .......... Will see what that breeds!
 
I built a fairly crude but effective system after a couple of breakdowns with a clogged primary filter. The fuel in my port-side tank was well manky and as the boat was on the mooring completyely emptying and cleaning the crud out was not feasible.
I bought an Ebay racor filter and a 12v pump and devised a settlement device using two semi-transparent 2 litre containers.
The fuel pick-up was a length of copper pipe on the end of flexible fuel line to reach the bottom of the tanks through an inspection hole.
It worked by circulating the diesel from tank - x2 settlement bottles - pump - racor - tank.
At the end I had about half a settlement bottle full of crud and a fouled racor filter, but clear fuel which I dosed.
It got me through last season. During the winter the tank was emptied and cleaned by hand for peace of mind. It proved barely necessary.
 
I've just 'polished' my fuel manually. Used a £5 hand pump to set up a syphon through a "Mr Funnel" filter funnel and into a jerry can. Any obvious gunk coming up was diverted to a separate container for disposal. Took a wee while but all done with existing things I had aboard.

I now have a slightly gunky filter in the funnel- any suggestions on how to clean it? Acetone, alcohol, etc?
 
A permanently installed polishing system will filter a lot more fuel than the small amount returned to the tank from the engine.

My small system filtered over 2000L of fuel last week alone in a very rolly anchorage.

The idea is filter the fuel multiple times picking up water and debris as soon as tank contents are stirred up.
Its not a panacea, but helps prevents problems and removes or at least delays the need to clean the tank. It also reduces the risk of diesel bug problem.

Fuel related problems seem to be getting more common and for the small cost involved, a fuel polishing system can be worthwhile addition.
 
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PabloPicasso said:
Hmmm I had not realised this. I guess this is the overflow as the fuel pump must deliver greater pressure than needed to maintain the integrity of the fuel delivery. Good to know though

So why the fuelpolishing 'industry'?
Click to expand...

Yes, all diesel engines deliver more fuel than is required to run the engine to the injector pumps; the excess is then returned to the fuel tank.

I think there are several situations that can require fuel polishing, though - I don't regard it as universally unecessary, just not applicable to my situation, where I have recently replaced the fuel tank so I know it has started out clean!

  • Not all engines recirculate as much fuel as mine does; in another discussion, it appeared that Volvo 2000 series engines do recirculate more fuel than most.
  • Old tanks may have contamination that has sunk to the bottom of the tank, and which can be stirred up by a rough passage, but which normal use won't disturb.
  • Old steel fuel tanks may rust from the inside, resulting in heavy debris that is only stirred up by a rough passage (that happened to me; hence the new fuel tank!).
  • An attack of the dreaded diesel bug may require more drastic treatment.
 
noelex said:
A permanently installed polishing system will filter a lot more fuel than the small amount returned to the tank from the engine.

My small system filtered over 2000L of fuel last week alone in a very rolly anchorage.

The idea is filter the fuel multiple times picking up water and debris as soon as tank contents are stirred up.
Its not a panacea, but helps prevents problems and removes or at least delays the need to clean the tank. It also reduces the risk of diesel bug problem.

Fuel related problems seem to be getting more common and for the small cost involved, a fuel polishing system can be worthwhile addition.
Click to expand...


Engines vary; what you say is generally true. But it happens that the Volvo 2000 series of engines recirculate more fuel than most engines do, and my remarks were specific to those engines.
 
AntarcticPilot said:
Engines vary; what you say is generally true. But it happens that the Volvo 2000 series of engines recirculate more fuel than most engines do, and my remarks were specific to those engines.
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Hey hey, my boat has a Volvo 2001 so i'm with you here. I have had the bug but have treated with marine 16, and more recently with soltron fuel treatment. Together with filter changes has worked so far.:)
 
pmagowan said:
I also don't understand the point unless you have had a disaster. Fuel polishing appears to be running fuel through a filter. My engine has a filter which the fuel already goes through. I carry spares. It has a water trap. Why the need for the duplication? If concerned, say at beginning of season, run the engine for a few hours and then change the filters.

P.s. the way I set up my filters changing them and bleeding only takes a moment and certainly less time than it would take messing around with a DIY fuel polishing kit.
Click to expand...
A clear factor here is the volume of fuel. My tanks hold up to 600 litres each, and I keep them half full. This reduces unnecessary weight, but allegedly makes them prone to gathering condensation.

Having seen what fuel bug can do on large scale tanks on Type 42 Destroyers sing water displaced fuel tanks, and then simple systems to prevent fuel contamination affecting these warships developed within only a few years of the problem being noted, my simple belief is that prevention is far better than cure.

Fuel quality is diminishing especially with the use of bio fuels (read manky old chip oil), fuel bug contamination is going to get worse and is already the number one cause of engine failure at sea. My rig cost less than £75, and £10 per annum for a new element. My tanks are inaccessible for mechanical cleaning, so for me polishing is a must. Each to his own, and what I do would be OTT for a 50 lt sailing yacht tank.
 
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