Racor 1000 filter change interval?

Riverguy said:

It's not more complicated. The complicated part (apparently) is the concept of the multi-phase absorption-precipitation-absorbtion-precipitation cycle. I think I've explained this three times, but some of the skeptics still don't get it, or maybe don't believe it.

Humidity in the tank can either be (a) absorbed directly into the fuel, or (b) condense on a cold surface and then be absorbed by the fuel. Either way the fuel is soaking up the water until it can't hold anymore (becomes saturated).

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Actually, it is more complicated. I understand the physics well regarding moisture transport. You state that humidity in the tank ullage space can either absorbed into the fuel or condense on another surface. Actually there is (c), as the tank warms, the humidity in the air is expelled with the air. It does not necessarily condense. Diesel is not hygroscopic, unlike ethanol gas.

There will be a small air exchange during thermal cycles, but the water in that air does lose its moisture unless it crosses the saturation line while in the tank. That is not a common situation.

Boating, huh? I joined because I thought there might be some boaters on here, but now I’m afraid there actually are.

Kill me now, I’m drawn to this thread like a moth and the poppyco never mind I’m just going to kill myself.

WTH? No, diesel is VERY hygroscopic...

Ski in NC said:

...Diesel is not hygroscopic, unlike ethanol gas....

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What? Of course it is...


LMGTFY

Riverguy said:

.


Anyway...Water's not the problem, it's the microbes that live off of the water and their corrosive bio-waste.

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Water is the problem, without it there are no microbes.
Perhaps fix the problem instead of applying the repeated bandaid biocide temporary fix.

Use a biocide, keep the bugs from growing, and sleep well at night.

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Nah, I'd rather stop the water, keep the bugs from growing, spend the money saved on beer and sleep even better at night.

BrianSmith said:

We've bought fuel in Nassau, Providenciales, and Salinas (PR) during that time. Since all fuel goes through the 2 micron filter before it goes into our "day tank", and that filter has never gotten really cruddy, I feel like we've never gotten any bad / dirty fuel.

As noted in the OP, the filter in the pic is 10 micron, and everything goes through 2 micron on its way into our day tank.

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How does the 2 micron filter look after a season or two?
Crude and water? How many gallons do you carry?

hollywood8118 said:

Good God we're doomed!


Yet there are those of us who have boats that never have water or any of the water living crud issues that if it really was that wet inside our tanks we would pumping out buckets of the stuff.


HOLLYWOOD

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At some point, debates with someone who can never be wrong, no matter how far up their kazoo their heads are, or how politely you try to explain why they are mistaken, become psychological studies into narcissism.

I'm spending my time explaining epistemology to my cat. Greater chance of a break through.

hollywood8118 said:

Good God we're doomed!

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:lol:

I personally think this "discussion" is excellent.
However I am still going to change my filters once per season just because.
And I like it when they look like this:

Riverguy said:

What? Of course it is...


LMGTFY

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Which brand of biocide do you use 'all the time"?

Riverguy said:

Currently own both the Mainship and the Bayliner.




Anyway...Water's not the problem, it's the microbes that live off of the water and their corrosive bio-waste. Use a biocide, keep the bugs from growing, and sleep well at night.

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Good point about warm and cold fuel, above and below ground storage, and the varying ability to hold water in suspension.

I disagree, water is a huge problem for metallic tanks, even if it's not supporting biological colonies. This is why, once again, I deem biocides a panacea, they address the symptom, not the cause. Water and no biological life is better than water and biological life, but water remains problematic, it shouldn't be dismissed as a mere nuisance.

Also, regarding water absorption by fuel in a tank, the inverse is also true, if the air in the tank is "dryer" than the fuel, i.e. it contains less water, water entrained in the fuel (not free water) will "evaporate" or be absorbed by the air.

Black contaminant in filters can be evidence of a microbial infestations (or more accurately its byproduct) or asphaltene contamination, the latter is mineral-based. Although some claim to clean tanks, no additive I've ever encountered will remove either of these per se, they need to be removed manually, by accessing and cleaning the tank.

smitty477 said:

One "O" ring had completely failed and we had just about 15 gallons of water in that tank - pumped it out with a vane puppy pump and a length of soft copper ice maker line snaked into the tank.

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As a note to anyone who has an aluminum fuel tank, do not use copper plumbing/dip tubes to access the tank. Copper is cathodic to aluminum (every metal except zinc and magnesium is) which means when the two are in contact with each other, and an electrolyte, i.e. water, the anode, aluminum, will corrode. Dragging a copper tube across the bottom of an aluminum tank will leave behind deposits of copper, where water will accumulate, this can set up the right environment for galvanic corrosion. Stainless steel and non-metallic tubes are preferred.

Steve DAntonio said:

As a note to anyone who has an aluminum fuel tank, do not use copper plumbing/dip tubes to access the tank. Copper is cathodic to aluminum (every metal except zinc and magnesium is) which means when the two are in contact with each other, and an electrolyte, i.e. water, the anode, aluminum, will corrode. Dragging a copper tube across the bottom of an aluminum tank will leave behind deposits of copper, where water will accumulate, this can set up the right environment for galvanic corrosion. Stainless steel and non-metallic tubes are preferred.

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Good point - the tube was coated with glyptal.

Wow. Take two cups of science, add 1 cup reality, 1 cup assumption, mix well in a well designed tank, and as my late gran would say, "There you are, you don't know where you are."

So what do we know?

1) Water can be held in suspension in diesel
2) The water/diesel interface can be a breeding ground for diesel bug

The point at which this becomes a potentially dangerous issue is in an emotional sea when the contents of your tank are being shaken around picking up the dead, brown, slimy bug from the tank's bottom and delivering it towards the engine(s) with the inevitable result of blocked lines and filters. Just when you need your engine(s) to stay working for you. Not the most helpful of results.

Given this potential, regularly adding a biocide is a good hedge, helping to reduce your anxiety levels when coping with nasty seas.

At the same time, the obvious regular tasks are:

a) keep your filters fresh (we do ours annually). Looking at their state will give many a good clue to what's going on.
b) ensure the O rings on your filler caps are in good conditions to minimise 'unnatural' water ingress.
c) only buy your diesel from a supplier which has a regular fresh turnover.
d) wait a good 24 hours after your supplier has had a delivery before you fill-up to give time for anything stirred up to have settled.

Having helped lead many cruise in company events (25+ boats per cruise) around the UK and Europe, diesel bug has always raised its head at some time during the cruise. I've lost count of the times I've had to tow.

Prevention is better than cure.

smitty477 said:

Good point - the tube was coated with glyptal.

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I love that stuff!