Installing a fuel polishing system

[weavis]

Guys.
Firstly I removed a couple of posts. I apologize as one was a reasoned response to the primary removed post but better to remove it that continue it. As I have moved into moderation duty, please continue with this interesting discussion.

[Dockhead]

Originally Posted by DeepFrz

Are you trolling?

What does the bottom of your fuel tank look like? If you don't know then you are passing an important, no, vital maintenance item. Just MHO.

Go easy on him, DeepFrz. He certainly knows what the bottom of his fuel tank looks like, because it's one of these:

[Matt Johnson]

I agree that it is way more hyped than needed. Very few cruising boats have a large enough tank capacity to not turn over their diesel once a year. If you don't, than maybe a polisher is beneficial.


1) Clean your tank
2) Filter the diesel through a Baja filter before it goes in the tank.
3) If you have to choose, set-up a dual Racor first.
4) Use your boat and be happy

We now have three tanks along with a day tank (4 tanks and about 150 gallons). Due to the valving and pump needed to transfer fuel between tanks, it was only one more valve to make it a polishing type system (pick-ups are not on the bottom since that is the hull, but instead slightly above this). If, like our old boat, we had only a 35 gallon tank, I wouldn't have added the polisher.

Matt

[Dockhead]

Originally Posted by a64pilot

Weavis, it would solve none of my issues, reason is because I'm not clogging filters, never have. adding additional filtration would do nothing.

And, I haven't read the rest of this thread, yet, but what 99% of what you gys are missing is that you can't actually install a proper fuel polishing system on most factory fuel tanks, you don't have the proper sized pick up, nor do you have it in the right place.

Now the boat with the centrifuge, that is a whole different animal than simply adding another filter and an electric pump.

This is certainly true, what you write, that the pickup MUST be in the right place for this to work!

But it's not actually that hard -- most factory tanks have a sump, with the fuel pickups for main, generator, whatever, quite a bit higher than that (30cm in my case, for the main engine). So all you need is a dip tube that gets reasonably close to the bottom of the sump, and it will work. If the discharge from the polishing system can be aimed at the bottom of the sump, and on the other side of it, and you have a reasonably high flowing pump, then Bob's your uncle

Better yet to have a drain in the bottom, forbidden by ABYC, but that's what I'll have on my next boat. The reason why it's forbidden is the risk of it working loose and dumping all your fuel into the bilge. I will deal with that risk in other ways.

[weavis]

A64

I dont disagree with the need or lack of need of a polishing system.

Here is where I with it.

I go to places with dirty fuel, not on purpose but it happens. Where you live perhaps your supply is good and all that is required is a filtration system and the occasional cleaning of the tank to get rid of varnish and stuff.

For me and others, traveling in remote places, its not that easy. In the Philippines one time, we collected fuel in containers and had to run it through a polisher before it even looked like diesel.....

You dont need it and I accept that. What I do know is the safety factor for me and others in our situation makes it a good deal. You may be able to get home from a Jerry can, but home for us is not that close. Also for the cost and peace of mind for long distance traveling, I think you would eventually get one after the first bad diesel. Its likely your Jerry can would also be bad fuel and then what do you do?

There is no insistence or imposition on people getting one- usually its a free choice after the event..

[a64pilot]

Weavis, except for the centrifuge, all these "polishers" are is added filtration. Nothing wrong with that, just don't try to act is they are something they are not
I have seen none that specifically had the compound in them that dries fuel by absorbing water, and they will NOT stop biological growth from occurring, as a Dr., you understand better than most how small a bacterium is and that a 30 micron filter will not filter bacteria. Most polishers are I bet 30 micron, I have asked a number of time what size filter people had, only to not receive an answer.
But I'm going to say this again, unless your having to change your polisher filter frequently, it's not doing anything.
Fuel polishing is not a replacement for a biocide.

[peter57]

Originally Posted by transmitterdan

A diesel engine polishes its own fuel as it runs. I have a Yanmar 4JH3e and our boat has 2 fuel tanks. I ran a test wherein we ran the engine for 2 hours taking fuel from one tank and returning it to the other tank. I wanted to transfer fuel from one side to the other and had no other easy way to do it. The return tank took on about 30 gallons of fuel over that 2 hour period. So basically every hour the engine runs it polishes about 15 gallons of fuel. So to me a separate fuel polishing system would seem to be a waste of money and a source of extra leaks. I think all diesel engines work the same way. When running they return a lot more clean fuel to the tank than they burn.

And if you have a bunch of sludge stuck to the walls of your tank no amount of polishing will clean it out. That requires scrubbing or power washing inside the tank.

I have the same engine. Unless your motor intake off the bottom of the tank? if it is not it will not polish the fuel. My PO has been changing filters for years to no avail.

[kmacdonald]

Originally Posted by Dockhead

Go easy on him, DeepFrz. He certainly knows what the bottom of his fuel tank looks like, because it's one of these:

Attachment 133816

Nope, that's not what it looks like. It's a below deck 12 gallon tank. Not diesel but gas. I rarely fill it since I don't like to store it long enough for it to go bad. I fill it from a five gallon can with gas purchased from a high volume roadside gas station. Just simple fuel management.

[kmacdonald]

Originally Posted by peter57

I have the same engine. Unless your motor intake off the bottom of the tank? if it is not it will not polish the fuel. My PO has been changing filters for years to no avail.

That's the "chasing your tail syndrome". I see it all the time. Good for the economy I suppose.

[Matt Johnson]

Does nobody filter while filling anymore? Pretty easy to takeout most contaminants and water before they are even a problem.

[a64pilot]

Guys, I'm out it the boonies and get a load of bad fuel, what is going to happen?
Answer it will clog my filter, what do I do, well I flip the lever to my other filter and run until it clogs, change them both and repeat.
OK, so now I'm out in the boonies with a fuel polisher and get the same fuel, what do I do? I run my polisher until it clogs a filter and replace it, run it again until it clogs and repeat, how many replacement filters do you guys carry for your polishers?

What is the difference? I'll tell you, about $2,000.


But, but what if its real , real bad like I get a whole bunch of watery gunk, what is your polisher going to do, it's overwhelmed with gallons and gallons of junk, and the filter will only hold a cupful.
What am I going to do? Well I'm going to take my dip tube out and insert a flexible tube and use an electric pump to pump as much as the junk out that I can get to by moving the tube around, I bet I get most, and I do have a dozen Racor replacement cartridges to get the rest.

If I feel the need, then I will hook that electric pump up to my dual Racors and run it as a polisher, probably take me 10 min to disconnect the engine fuel line and slip on a hose to return fuel to the tank, actually I have a pump on it already to make bleeding easy, so all I have to do is disconnect the engine and run a hose back to the tank

What is your polisher going to do that I cant?

[a64pilot]

Originally Posted by funjohnson

Does nobody filter while filling anymore? Pretty easy to takeout most contaminants and water before they are even a problem.

I was going to point out in my earlier post that I won't ever get the worst case scenario of gallons of watery gunk, cause my Baja filter will alert me to that before it get into the tank.

[a64pilot]

Now I will make a concession for the polishers,

If you have or will have a common rail Diesel, then for goodness sake, do the polishing, but do it right, very high volume to get a swirl in the tank and have a centrifuge to get the fuel really, really clean. Common rails Achilles heel is dirt, the injectors will not tolerate it.

[Dockhead]

Originally Posted by a64pilot

Guys, I'm out it the boonies and get a load of bad fuel, what is going to happen?
Answer it will clog my filter, what do I do, well I flip the lever to my other filter and run until it clogs, change them both and repeat.
OK, so now I'm out in the boonies with a fuel polisher and get the same fuel, what do I do? I run my polisher until it clogs a filter and replace it, run it again until it clogs and repeat, how many replacement filters do you guys carry for your polishers?

What is the difference? I'll tell you, about $2,000.


But, but what if its real , real bad like I get a whole bunch of watery gunk, what is your polisher going to do, it's overwhelmed with gallons and gallons of junk, and the filter will only hold a cupful.
What am I going to do? Well I'm going to take my dip tube out and insert a flexible tube and use an electric pump to pump as much as the junk out that I can get to by moving the tube around, I bet I get most, and I do have a dozen Racor replacement cartridges to get the rest.

If I feel the need, then I will hook that electric pump up to my dual Racors and run it as a polisher, probably take me 10 min to disconnect the engine fuel line and slip on a hose to return fuel to the tank, actually I have a pump on it already to make bleeding easy, so all I have to do is disconnect the engine and run a hose back to the tank

What is your polisher going to do that I cant?

You've asked exactly the right question

And now I'm going to answer it


The difference is that your main engine filter only gets the crud when it gets stirred up. Which means the crud will lurk there until you get into rough weather when you most need the motor, and then you're screwed. That's not the time you want to be dealing with it!

The polisher will take out the crud straight away. Even while the engine is running! That is a big, big difference. Or at the dock without the engine running, and without risk of engine stoppage.


My setup is just like yours -- I have dual Racors, and count on the case of filters I have on board, and flipping back and forth, to keep going in case of a problem.

HOWEVER -- once it gets to that, you're already in deep trouble with a ton of crap in the bottom of the tank. My main engine pickup is 30cm above the bottom of the sump. IF I had a polisher (and I will on the next boat), I would be able to detect and solve the problem instantly, far earlier than when all this takes place.

A polisher is NOT merely extra filtration. It is getting at the bottom of the tank so that you can get any drop of problem, when it first occurs. By the time the problem gets up to the level of your main engine pickup, you're in a world of hurt.


Note that a very common source of fuel problems, is leaking deck fillers. These things are the work of the devil! Should be against the law. Mine fortunately is up in my coachroof, safely above deck level, but 99% of boats have them set in the deck, where not tightening it completely or having a slight defect in the o-ring means seawater goes straight in, either a drip or a torrent. With a polisher, you will see this the first day, get rid of the water, know to find the source of the leak. Without a polisher, you have to wait until your tank has got many gallons of seawater in it, or you get into a storm. Ick!

[peter57]

Originally Posted by kmacdonald

If the diesel is old enough to create sediment and gum it is no longer good and should be discarded. If you "polish" it you will have clean bad diesel. Having a filter between the tank and engine "polishes" the fuel before entering the engine. A fuel "polishing" system does not enhance the process. Diesel is good for about 18 months in cold climates and only 6 months in hot climates. "Polishing" diesel doesn't do anything to prevent diesel from going bad. Don't be "polished" by old wives tales.

I have gunk and water in the bottom of my tank and there is no way the motor fuel system is going to polish it. With a tank in the keel and no way of a successful clean.
Some of us need a polisher to clean our tanks. I have a 1/2" annealed copper pipe connected to the polisher that I sit on the bottom of the tank and move it from place to place as much as possible horrible stuff on the bottom, lift the pipe to about of the pick up for the day tank it is clean.

I will make this permanent fixture soon to keep the bottom of the tank clean as possible and only used periodical or more if the filters tell me too.

Cheers.