Budget diesel polishing

wandeerer

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I've managed to save a wad by setting up an emergency diesel polishing system, after finding diesel bug in a belly tank again. I do carry a 12vdc portable diesel transfer pump for cruising. It pumps 40 litres a minute. Being a very practical yachtsman, my mind is always looking for easier solutions to the commercial options and I happened to have two 10" plastic water filter housings that were going to used for the freshwater footpump to basin project. Mmm - I filled them with diesel and left them until the next boat visit a week later.. Eureka! Not at all affected by diesel.Popped off to the local bearing supplier and picked up two sets of nitrile o rings and a few brass fittings and then to the local hardware for a few 10 and 5 micron blown pp water filters and a 3 way valve. Happy to say that it polished almost 80 litres and used 4 filters. No damage to the clear plastic housings . This piece of kit is now plumbed in via two bypass valve ready for the next Atlantic crossing. PS - NOT suitable for gasoline/ petrol.
 
10 and 5 micon filters ? Suitable for filtering the crud and dead bug accumulation ..... but

To actually be effective and filter out 'bug' itself - you need BETTER than 2 micron .... even then you will not succeed in 100% removal.

Fuel polishing does not cure / solve the problem ... all it does is remove the crap left behind by the infestation.
 
10 and 5 micon filters ? Suitable for filtering the crud and dead bug accumulation ..... but

To actually be effective and filter out 'bug' itself - you need BETTER than 2 micron .... even then you will not succeed in 100% removal.

Fuel polishing does not cure / solve the problem ... all it does is remove the crap left behind by the infestation.
But isn't it that crap that stops your engine?

Wont the bug itself just burn, baby, burn after its been through your injector?
 
Correct - but the bugs die .. they deposit crap ....

What are you going to do ? Run a 2micron continuously to stop your engine getting 'gunged up' ?? Stopping to change filters every so ofrten ??
I was assuming (and am still so inclined, though I could be wrong) that, provided the accumulated dead bug crap was filtered out, which the filters described apparently do, the 2 micron bacteria that get past them, whether alive or dead, would burn harmlessly in the engine.
 
Being a very practical yachtsman, my mind is always looking for easier solutions to the commercial options and I happened to have two 10" plastic water filter housings that were going to used for the freshwater footpump to basin project.
The cheap Racor filter knock-off housings are an alternative choice. The advantage is that these are designed to remove water, one of the key advantages of regularly polishing fuel.
 
I was assuming (and am still so inclined, though I could be wrong) that, provided the accumulated dead bug crap was filtered out, which the filters described apparently do, the 2 micron bacteria that get past them, whether alive or dead, would burn harmlessly in the engine.

And the gunge that accumulates between polishing ?

If you open up a fuel filter that has bug ... you see the typical gungey mess accumulating on the filter - that eventually leads to blocked filters ...

Instead of fuel polishing ... just get a decent Enzyme based Additive and add to that each fill-up ... that will break up the crud .. break up moisture in the fuel ... all will pass through and be burnt .....
 
We polish the fuel most days. An additive to kill the diesel bug is essential, but continually removing the carcass and deposits is helpful. It is also of benefit to remove any water from the tank to prevent conditions where the diesel bug can proliferate.

It has worked for us. Systems to achieve this are not expensive.
 
Keeping the fuel dry prevents the bugs from growing. They live in the water at the water fuel interface, feeding on the fuel. So if you keep the fuel dry there is nowhere for the bugs to live. I fitted a Chinese Racor 500 copy to my prior portable polishing unit and then installed a polishing system on the current boat again with the Racor copy. Result the fuel is dry and bug free, indeed in the two years since I fitted the system I am still on the same Racor element, and yet to find any water at all in the bowl. I run the system at least every 2 months for an hour or two.

Also there are only two principal places water in a tank can likely emanate from ...

1 With the fuel you purchase - so polish religiously after every refuel.

2 The deck filler cap - liberally grease the threads with a waterproof grease. Ok your fingers get a bit mucky when refuelling - hey ho.

Keep the fuel dry - keeps the bug away, and not an additive anywhere near.
 
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