Funky Fuel filters....>>

On my "new to me" boat, I'm in the process of re-plumbing my fuel system and adding a light duty polisher. The Previous to the previous owner installed a 27 micron Fleetgaurd water separator ahead of the Existing Racor (10 micron filter) about 4 years and 300 hours ago. Not seeing any replacement of these in the logs, my re-plumb job presented a perfect opportunity to put in new filters. They were pretty funky as you can see. The new system will pull through a Fleetgaurd ($13) then a 10 micron Sierra cannister ($7) for the polishing, then on to a 10 micron Racor and the on engine cannister filter on my volvo when running. 4 filters....Overkill you may say? Maybe, Maybe not. Better safe than sorry I say. The caveat is, the engine was running just fine when I tackled this project. The Fleetgaurd should capture the majority of the crap as it has from these pics. The rest are icing on the cake.
I'll be changing filters on a more regular basis from now on!
There's a moral to this story somewhere!

Racor and Fleetgaurd:






Walbro Pump (FRA-4) and a single "Y" valve to activate the polishing system..All the re-plumbing installed today. Simple and inexpensive.

Fiber on filters will pick up asphaltenes, commonly found in older oxidized fuel. They are typically soft and not necessarily harmful to your fuel pumps or injectors.

Black filters like that are typically indicative of old fuel.

Northern Spy said:

Fiber on filters will pick up asphaltenes, commonly found in older oxidized fuel. They are typically soft and not necessarily harmful to your fuel pumps or injectors.

Black filters like that are typically indicative of old fuel.

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Yeah, I would assume that's the case...Only 50 hours accumulated in the past year, and sat for quite some time before that.....(2 60 gallon tanks). I'll be exercising it quite a bit more this season..

The moral of the story is, a low fuel flow engine can run along just fine until it's filter elements are completely blocked off.

Filter Autopsy at 300 hours....NOT pretty!

If you run or polish on low fuel you will get rid of the junk faster that if you fill the tank.

Do you have any access plates on the tank?

Fuel that dirty needs real agitation or access to the interior of the tanks to get clean. As Bruce mentions keep the tank levels low if you try to filter it clean. But it needs to be stirred up very well as you filter it. You'll need to use a pump capable of high flow rates and some decent pressure to have any hope of moving the fuel around in the tank. Even then it's hard to get the fuel agitated in all the baffled areas without access.

Heron said:

Filter Autopsy at 300 hours....NOT pretty!

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' DAMN!!
Dude! Where's my fuel polisher?

I think the new ultra low sulfur diesel is more subject to developing asphaltenes than the previous formula. A lot of people mistake the asphaltenes in their fuel for algae and start dosing their tanks with algicides. I have been using Stanadyne additive in my fuel because it claims to reduce asphaltenes. Anyone found a better preventative for asphaltenes other than a fuel polishing system?

bayview said:

If you run or polish on low fuel you will get rid of the junk faster that if you fill the tank.

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I'm at about 30 gallons per tank now so I should be able to run a few polishing cycles fairly quickly and clean it up.

Capt.Bill11 said:

Do you have any access plates on the tank?

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No, Not accessible...But I will provide some agitation as I start the Cleaning process.

BlueYonder said:

I think the new ultra low sulfur diesel is more subject to developing asphaltenes than the previous formula. A lot of people mistake the asphaltenes in their fuel for algae and start dosing their tanks with algicides. I have been using Stanadyne additive in my fuel because it claims to reduce asphaltenes. Anyone found a better preventative for asphaltenes other than a fuel polishing system?

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Good point. I use Stanadadyne in my Diesel VW . There are apparently some specific additives to deal with these (common) asphaltenes...See my new post down a few.

At 300 hours on that filter, it can obviously deal with quite a lot of crap and still run perfectly. A regular filter change schedule is now on the maintenance list..
I think it was an out of sight, out of mind thing for the previous owner as the boat continued to run perfectly.. All other systems were upgraded and maintained well..

I'm missing something but perhaps because I don't recognize all the items you mention correctly. However, all I saw was filters, not any centrifuge or actual polishing equipment. Am I wrong?

BandB said:

I'm missing something but perhaps because I don't recognize all the items you mention correctly. However, all I saw was filters, not any centrifuge or actual polishing equipment. Am I wrong?

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I am re-doing the Fuel system on my boat. It is only filtered now (Fleetguard, Raor, and Volvo canister). A light duty polisher is being installed.

BTW, I've researched the Asphaltene problem and apparently it is quite common with the new low sulphur fuels as mentioned. This is exactly what is seen here on these filters.
Read more about it here: Asphaltenes and Fuel Filter Plugging

More than a few of us likely have this condition. There are specific conditioners available to minimize the issue. Apparently you need to disperse the asphaltenes, not just circulate. I'll be adding these to the fuel regimen:

Like: Fleet-Tech Asphaltene Conditioner, Quart CC2597

Or: Amazon.com: Penray 105032, Total Diesel Fuel System Cleaner - 32 fl. oz: Automotive

Heron said:

I am re-doing the Fuel system on my boat. It is only filtered now (Fleetguard, Raor, and Volvo canister). A light duty polisher is being installed.

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What polisher are you installing?

Yes, reduced to layman's terms, filters remove particulates while polishers remove water, sediment, non combustible particulates and microbial contamination. Polishing also in doing so restores fuel to specifications. Actually filtering by itself can pull the fuel out of specification by removing combustibles.

And you're very right about fuel downgrading much quicker than it once did. I've seen quotes that the "shelf life" of today's diesel fuel is between 6 months and 12 months.

I only understand the very basics and the theory but the science of how polishers work is a bit beyond me. I just know they do work.

Heron said:

Filter Autopsy at 300 hours....NOT pretty!

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The picture of that filter and your statement that the engine was running just fine at the time you removed the filter just reinforces what I've seen to be true with low fuel use engines.
That your money is best spent first buying large capacity filters with large surface area element before buying a fuel polishing system.

Low GPH engines flow so little fuel that with even badly clogged large capacity filters they will still run fine. Plus any time you are running your engine you are "polishing" your fuel.

It also reinforces my skepticism of the valve of vacuum gauges for low flow engines.

Capt.Bill11 said:

The picture of that filter and your statement that the engine was running just fine at the time you removed the filter just reinforces what I've seen to be true with low fuel use engines.
That your money is best spent first buying large capacity filters with large surface area element before buying a fuel polishing system.

Low GPH engines flow so little fuel that with even badly clogged large capacity filters they will still run fine. Plus any time you are running your engine you are "polishing" your fuel.

It also reinforces my skepticism of the valve of vacuum gauges for low flow engines.

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I think you're right on the money. That big fleetguard pretty much proved that. My burn rate is typically 2-3 GPH. As to my "Polisher", I should probably call it a supplemental recirculator. Just a Walbro pump and a "Y" valve pulling fuel through 2 filter/separators of Decreasing Micron ratings and able to run while stationary for a little extra cleansing. Cheap ($200) and simple enough to do and will allow fuel transfers from tank to tank, and filter priming as a side benefit..

In the future, some Asphaltene conditioner and regular replacement of 2 inexpensive spin on water separator filters once a year should do the trick..

Keep in mind, that filter shows a 5 year and 300 hr build-up..

300 hours over 5 years? Now that you say that are you sure your tanks are really that dirty?

Capt.Bill11 said:

300 hours over 5 years? Now that you say that are you sure your tanks are really that dirty?

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I don't believe they are at all...From logs of previous owners the boat has NEVER had a fuel related problem and likely won't in the future unless I take on a load of bad fuel. I think this is more of an age issue.

Once I put in new filters, condition the Asphaltenes and start really using the boat and running some fuel though it they'll likely be clean as a whistle. I've only had the opportunity to put 12 hours on it since the December purchase.

I get the picture now. Sounds like a good plan you have.

Pulling fuel thru four filters " over kill you say". Maybe but it's not the best thing for the longevity of your fuel pump. Better to stick with a standard primary and secondary fuel filter set up. Let the Walbro recirculate the fuel thru a filter/water separator on the fuel tanks which can be done underway or at the dock to polish the fuel.

HiDHo said:

Pulling fuel thru four filters " over kill you say". Maybe but it's not the best thing for the longevity of your fuel pump. Better to stick with a standard primary and secondary fuel filter set up. Let the Walbro recirculate the fuel thru a filter/water separator on the fuel tanks which can be done underway or at the dock to polish the fuel.

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I've been pretty impressed with the effectiveness of my 3 filter system given how that fleetguard looks! Had that not been in the system the previous owner would have gone broke replacing those little Racor filters had the asphaltene issue not been addressed. The secondary 10 micron polishing filter will be by-passable with a valve while running leaving me with the exact 3 filter configuration that I (successfully) had. I have a vacuum gauge on the system as well. The Walbro is inline so can be left off (flow through design) or pump to the engine or to the polishing circuit with a "Y" valve. All in all it will be pretty simple and versatile in both run and polish configurations. All are water separators. No worries!

When i bought the boat, it had about 100 gallons in the two tanks. After putting about 300 gallons in my tanks on the first fill, and going up the east coast in some rough weather, my filters looked like that at the first filter change.

My fuel polisher also took about 2 gallons of stuff that looked like that.

i did open the inspection port, but the tank was clean, all the agitation had done all the work already.

not a problem since.

We bought our Defever 44 about a year ago. Took her home (about 1000 miles and 150 hours) with the filters that were on board. We did have the fuel polished dockside in Palm Coast before leaving. No water, no crud was evident even though the boat was little operated the three years previous to purchase. Cruised home through some very rough seas in St. Andrews Sound so the tanks were most definitely stirred up. Still nothing in the bowls. Changed out the 2 micron filters when we arrived at our home port near Annapolis. The filter elements were hardly discolored. Although I have no way of knowing for certain, it would appear that my tanks are pretty clean. Either that or the tank crud is firmly stuck to the bottom.

From the looks of those filters I'd say you might also have a water in fuel problem to solve. It's easy to check if the filtered material is asphaltene or organic by placing a bit of it in a bath of acetone. If it dissolves it's asphaltene. Can you drain the fuel from the bottom of the tank into a clear bottle to have a look see?


Via iPhone.

cafesport said:

From the looks of those filters I'd say you might also have a water in fuel problem to solve. It's easy to check if the filtered material is asphaltene or organic by placing a bit of it in a bath of acetone. If it dissolves it's asphaltene. Can you drain the fuel from the bottom of the tank into a clear bottle to have a look see?


Via iPhone.

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Thanks for the tip. I put some of the filtered material in Acetone and it did, in fact, dissolve. From this info and the visual I think Asphaltene is confirmed.

No access to the bottom of the tank, but I can drop a hose in and pump some fuel out to check that.

I have some Asphaltene chemicals coming tomorrow and my polisher/circulator is one fitting away from completion. I'll do a cleanse on Thursday.

On water, don't know. Remember those filters are 5 years and 300 hours old. The boat has never had a problem with fuel delivery. All new filter/separators were installed today. I think I'll have it all corrected shortly..

Asphaltene dissolved:

Funky stuff on the first filter from newly-built tanks:

One thing you might also want to consider is that Racor recommends installing their filter on the suction side of any transfer pump. This prevents pressurized emulsification of any water which may be present upstream of the filter. Also the turbine is designed for a specific flow rate and needs to be properly sized in order to do its job effectively (for the walbro the 500 is the size you need). The large fleet guard upstream when plugged may prevent this. Do you know the return rate of fuel for your engine? If your tank/tanks are getting all the return fuel, a rise in temperature could be contributing to the asphaltene precipitation you have been seeing.


Via iPhone.

cafesport said:

One thing you might also want to consider is that Racor recommends installing their filter on the suction side of any transfer pump. This prevents pressurized emulsification of any water which may be present upstream of the filter. Also the turbine is designed for a specific flow rate and needs to be properly sized in order to do its job effectively (for the walbro the 500 is the size you need). The large fleet guard upstream when plugged may prevent this. Do you know the return rate of fuel for your engine? If your tank/tanks are getting all the return fuel, a rise in temperature could be contributing to the asphaltene precipitation you have been seeing.

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I Want to retain the Racor for running filtration only (along with the Fleetguard and Volvo on-engine filter) as it has been running now (and the past 5 years). All are water separators. Based on those pics I highly doubt that fleetguard will ever plug with regular change outs from now on. I's the first filter in-line and will capture the bulk of any junk in the system. It can capture a whopping amount as evidenced by the pictures. The pump is really for at dock circulation/polishing and "Y's" just before the Racor. Fuel will be filtered down to 10 microns with the "polisher". All water issues, should I have any, will be captured by the 2 water separators upstream. Both accessible and easy swapped or drained of water. Dunno the return rate or temps of the fuel (Volvo TAMD41P 200hp turbo) and there's not much I could do about that anyway. Asphaltene conditioner, some fresh fuel and regular running seem to be the solution.

Again, despite the gruesome pictures of that filter, the engine has continued to run perfectly. Just a long deferred maintenance issue by the previous owner(s). The new system is simple (one switch and one valve) and will be worlds better as well as versatile.

Just an update on my "New" system. Filters all replaced and the polishing function run several times. Asphaltine Chemicals added and fuel bowls look clean. The Walbro filters/Transfers 30 GPH (observed) which is more than adequate for my dual 60 gallon tanks. It's nice to be able to move fuel while at the dock. As small as my boat is, an empty tank on one side and a full one on the other results in a pronounced list!
I can balance things nicely now and filter at the same time. Works great!

Heron said:

It's nice to be able to move fuel while at the dock. As small as my boat is, an empty tank on one side and a full one on the other results in a pronounced list!
I can balance things nicely now and filter at the same time. Works great!

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Same on larger boats with fuel tanks on opposite sides of the keel line Heron. I have four tanks in the stern and sometimes I forget to reopen the crossover fuel line on longer cruises. My generator only draws from the starboard tanks. After a couple of weeks of light cruising and prolonged anchoring out, the stern rises and boat will develop a pronounced list to port. If you let it go long enough even rain water will begin to puddle on the starboard deck.

Since we're showing each other our nasty business, here's what the Racor looked like when we bought the boat (there's the Racor, then a large fuel filter, then another one on the engine)