Diesel Polisher Diy

[Cheesey69]

Hi all,

I've got the basics together to make a portable fuel polisher,

1  racor fuel filter

2 CAV type twin filter

3 Hand prime pump

4 12volt pump

I've gone with the racor first because the filters easy to change.

The problem is, there is no drain tap at the bottom of my tank (at least what I can see) and I was hoping to use this. I don't really want to put a take off point in what is now an air tight line so do you think I could get away with a long copper pipe into the bottom of the tank?

And some say chanel the cleaned fuel into jerry cans but 45 gallons is a lot of cans so is there anything wrong in recycling the flow? I know it might take longer but no damage?

silly questions I know but I'm determined to keep those break downs to a minimum. 

thanks  

[Smoggy]

A pipe to the bottom would be better as the pick up probably leaves a dead area below where the crud and water collects, slight slash cut to the end would help.

[Smoggy]

Recycling back to the tank means the system can run for much longer and pass through a few times, rock the boat as much as you can while the polishing setup is running to stir it up as well as the crud will settle and will only be stirred when you hit choppy water (not that it's going to happen badly on the broads even on breydon).

Most river/coastal boats are fine until they get the first good shake up then it stops abruptly in the worst place it can find.

[annv]

Hi DO NOT ROCK THE BOAT TO STIR THE DIESEL if you dont have a drain of pipe there will most proberly be water in bottom of tank this needs to be removed first, i use a large glass coffee jar place your copper pipe in lowest part of tank when water removed then suck diesel into as many cans that you have,  then when you do your polishing etc try to suck from as far away from replacement hose, then leave the cans to stand for as long as you, then when replacing the cans   place suction pipe two inches above bottom of cans then clean polish etc and return to fuel tank, you can then check the diesel thats left in the cans , It is bad practice not to have a drain tap in lowest part of tank BUT!! it may be impracticable to fit one so at start of each year suck some fuel from lowest part of tank to remove water. John

[Smoggy]

A racor filter should show water straight away assuming it's a turbine type, the faster the fuel flow the better they work as they spin the fuel as it goes through and water being heavier spins to the outside and into the bowl.

If you have a vent fitting opposite end to the filler that is the best place to return the fuel.

[Cheesey69]

Thanks all

[JanetAnne]

Just in case anyone is unsure, this came out of a broad cruiser a couple of weeks ago

over two gallons of water and once apart we found an inch of slime laid in the bottom of the tank.

[Oddfellow]

The portable polishing systems you can buy tend to just cycle it through the tank. It will take a LONG time. 

 

[annv]

A Racor filter will not stop the formation of diesel bug that forms/grows at the boundary of the water and diesel dont let water stand in the tank! and if a steel tank rust/corrosion can form. John

[Cheesey69]

True, that’s what hopefully the bug treatment I put in does (as recommended by griff)

just trying to remove the rubbish at bottom of any tank. Will look more carefully or at least think about getting a drain tap or plug put in. 

[Smoggy]

I was never advocating leaving water in the tank, if it's there it needs shifting, but the racor should still show the problem if it is there by the bowl filling with water.

When I did a fuel tank cleaning job on my last boat I used 10" string wound filters in clear housings and a good rocking shifted loads more crud than sat still, if it's not stirred up it won't come out.

[TheQ]

Note, drain TAPS are illegal on fuel tanks according to the BSS, they must be drain plugs that require a tool such as a key or spanner to open. Rule 2.8.1

 

On my DIY diesel polisher I have a glass demijohn before the filter,

So I have a 4ft, 1/4nch copper tube to reach the bottom of the tank.

Rubber tube,

Then the diesel fuel lift pump.  (Doesn't require priming)

Rubber tube,

1/4 inch copper pipe to  the bottom of the demijohn, 

1/4 inch copper tube from near top of demijohn to Rubber pipe

Rubber pipe to fuel filter, 

Fuel filter to return rubber pipe.

The demijohn allows much of the water to settle out before the filter.

When I go down to the boat to work on it the polisher is set up and left running not much comes out now, but on the first run a couple of gallons came out..

[annv]

Drain taps on fuel tanks are NOT illegal BUT must have a blanking cap on end of tap to stop drips and leaking. John

[TheQ]

19 hours ago, annv said:

Drain taps on fuel tanks are NOT illegal BUT must have a blanking cap on end of tap to stop drips and leaking. John

only if that cap requires a tool or key to remove it..

2.8 Fueltank connections 2.8.1 Is the fuel tank drain fitted with a plug or cap which can only be removed with tools? R Check each fuel tank for the presence of a fuel drain facility. If present, check the drain outlet for the presence of a plug, cap or blank. If present, the outlets from fuel tank drains and drain valves must be terminated with a ‘tools‐to‐remove’ plug, cap or blank.

NOTE – the provision of a fuel tank drain facility is not a requirement. NOTE ‐ The plug, cap or blank must be of proprietary manufacture and/or metallic and it must be fixed in place by a screw mechanism which requires a tool to remove it.