Sludge in the fuel tank

[Siberian Sea]

Your problem starts with the fact you have water in the bottom of your fuel tank. It gets there from one of three ways. First it was introduced with the fuel you put into the tank, second way it leaked into the tank through for example a poorly sealing fuel filling cap or third through condensation inside the tank that can occur when tanks are left partial empty for periods of time.
Now what’s this slime? Well this slime is the waste produced by a very unique algae that live not in your fuel or in the water in your tank but rather it lives in this very thin layer between the water and fuel. This algae is special because it needs no light for growth. It gets its oxygen from the water and it’s energy by consuming the hydrocarbon diesel. This algae is microscopic, you cannot see it but you can see the waste it produces as a dark slime that eventually plugs your filters.
Now it’s said often you can just add some chemicals and kill this algae and problem solved right? DONT go this path to solve this problem. You need to remove its habitat and you do this by removing the water in your tank. Best is to drain off the bottom of the tank, or next you can get your tanks/fuel “ polished “ or if the problem is not to severe you can add a diesel fuel additive that breaks down the water molecules and suspends it in the fuel and it passes with the fuel into the combustion chamber and is burned. Remove the water, remove the water.
I venture to say your engine will not start because you have failed to bleed all the air from your system.

[theoleduc]

Hello, follow the step by step process by summarized by "lordgeof"... I had a bacteria contamination a few years ago and I cleaned up my two 300 gallon tanks myselve. You have to open the tanks. I even cleaned the tanks with a high pressure Karcher in order to ensure that all bacteria sh... which sticks like glue to the baffle welding is gone. Lots of work and messy. I do not believe in a quick polishing exercise for a heavily contaminated tank... there is no way one can create enough turbulence in the tank via a filling opening and extract the sludge.
Use biocide every time you fill up. Fill up tanks before winter and add a killer dose.
Success! Theo / Ritser

[DeValency]

I had an almost similar issue. The engine started ok but after some time stopped. That’s AFTER everything in the fuel system has been replaced and after a thorough cleaning of the 95 gallons tank. Two different mechanics tried for hours to locate the issue.
Only the third one, after taking apart the Racor filter found out that some sticky sludge under the internal non return ball that seats at the lowest interior part of the filter captured the ball after some operating time. Once cleaned and well washed, never experienced any problem.

At any case, cleaning of the tank and the entire system is critical and after that use the engine for a few hours and few times at a safe area before planning a long offshore trip.

Originally Posted by s3raphim

Hello,

I have a 1978 Cal 39 MkII here in Seattle, WA. She has a Perkins 4108 with dual Racor 75/500 FGX primary filters (10 micron), and a 2 micron secondary filter at the engine.

I had the filters changed last month and the mechanic who did the work said (about the Racors) that he'd never seen as dirty a filter. I figured this was because the previous owner hadn't changed it, and I was a year in to ownership. At any rate… just 1 month and 10 engine hours into the new filters, the engine died at sea and I had to emergency anchor and then get towed into my slip.

On inspection, the port side Racor filter was black and coated with a bit of dark sludge. I have a 2”” inspection port at the top, and was able to take a photo inside the tank.

See photos below.

I replaced the filter myself, in an attempt to simply get the engine running, but the engine still won’t start.

It’s very likely that I didn’t bleed the engine correctly, or perhaps the sludge has gummed up the primary filter (which I haven’t changed), or the fuel injectors (please, Lord, no!).

My knowledge of bleeding the engine is strictly from researching online posts. I know enough to be dangerous, and it seems like a real chore. I was able to bleed the top fitting on the primary engine filter, and the fuel injector fittings themselves. I was NOT able to bleed the fitting at the top of the governor, as for the life of me I could not fit a wrench or socket into that small a space.

At any rate — my thoughts are to figure out or hire someone to properly bleed the engine, with new filters all around, just to get her running again… and then to immediately determine the scope of issues in the tank.

The tank is 57 gallons and about 15% full. I believe my error was in not keeping the tanks topped up over the winter, and I assume some sort of moisture has entered in.

INSIDE THE TANK


CLEAN STARBOARD RACOR


DARK PORT SIDE RACOR


PORT RACOR FILTER W/ SLUDGE


So the question becomes paying someone to polish the fuel and clean the tanks, or trying to do the grunt work myself.

Would love any thoughts/advice from people who’ve gone through this process in the past, or might have a recommendation of a person, service, or yard here in the Pacific NW to help.

And on that note, I would ALSO really love to find "a guy" who knows Perkins 4108's and who I could pay to spend a few hours training me on engine basics (filters, oil change, bleeding the system, pencil zincs, other misc maintenance issues).

Thanks in advance,

Sean
1978 Cal 39 MkII S/V AIOLOS
Seattle, WA

[Bullshooter]

I didn't notice anyone mention that with all this contamination, it would be wise to carry a small (5 gallon +/-) portable fuel tank, preferably with filter(s), to at least avoid getting stranded until all contamination issues are sorted. A new portable tank with new fuel could possibly allow you to get out of the marina and sail in the mean time.

Having one may also aid in diagnosing the possible bleeding of air problem noted.

[Reddogg]

Sean I would greatly appreciate speaking with you regarding the filter issues. My name is Bill Miller and I have been with AXI International for over 21 years now. Our website is www.axi-international.com and my number is (239) 707-1606.

Best regards,
Bill Miller

[David B]

Originally Posted by s3raphim

Hello,

I have a 1978 Cal 39 MkII here in Seattle, WA. She has a Perkins 4108 with dual Racor 75/500 FGX primary filters (10 micron), and a 2 micron secondary filter at the engine.

I had the filters changed last month and the mechanic who did the work said (about the Racors) that he'd never seen as dirty a filter. I figured this was because the previous owner hadn't changed it, and I was a year in to ownership. At any rate… just 1 month and 10 engine hours into the new filters, the engine died at sea and I had to emergency anchor and then get towed into my slip.

On inspection, the port side Racor filter was black and coated with a bit of dark sludge. I have a 2”” inspection port at the top, and was able to take a photo inside the tank.

See photos below.

I replaced the filter myself, in an attempt to simply get the engine running, but the engine still won’t start.

It’s very likely that I didn’t bleed the engine correctly, or perhaps the sludge has gummed up the primary filter (which I haven’t changed), or the fuel injectors (please, Lord, no!).

My knowledge of bleeding the engine is strictly from researching online posts. I know enough to be dangerous, and it seems like a real chore. I was able to bleed the top fitting on the primary engine filter, and the fuel injector fittings themselves. I was NOT able to bleed the fitting at the top of the governor, as for the life of me I could not fit a wrench or socket into that small a space.

At any rate — my thoughts are to figure out or hire someone to properly bleed the engine, with new filters all around, just to get her running again… and then to immediately determine the scope of issues in the tank.

The tank is 57 gallons and about 15% full. I believe my error was in not keeping the tanks topped up over the winter, and I assume some sort of moisture has entered in.

INSIDE THE TANK


CLEAN STARBOARD RACOR


DARK PORT SIDE RACOR


PORT RACOR FILTER W/ SLUDGE


So the question becomes paying someone to polish the fuel and clean the tanks, or trying to do the grunt work myself.

Would love any thoughts/advice from people who’ve gone through this process in the past, or might have a recommendation of a person, service, or yard here in the Pacific NW to help.

And on that note, I would ALSO really love to find "a guy" who knows Perkins 4108's and who I could pay to spend a few hours training me on engine basics (filters, oil change, bleeding the system, pencil zincs, other misc maintenance issues).

Thanks in advance,

Sean
1978 Cal 39 MkII S/V AIOLOS
Seattle, WA

When you have your tanks and lines clean, my suggestion is to always use a decent biocide at every fill, and an extra dose if you put your boat into hibernation for winter.

Its also nice to use your own filter funnel when filling, but I must admit, that becomes a hassle at times.
So far with that practice (the biocide), nine years on, our tank is still clean.

The other thing we did from early on is a pair or switchable clear-bowl filters so:
1. we can see what's happening (totally clear)
2. if we do get an issue, we can quickly switch over to a new filter while servicing the blocked one.

[billy_boat]

Originally Posted by s3raphim

Hello,

I have a 1978 Cal 39 MkII here in Seattle, WA. She has a Perkins 4108 with dual Racor 75/500 FGX primary filters (10 micron), and a 2 micron secondary filter at the engine.

I had the filters changed last month and the mechanic who did the work said (about the Racors) that he'd never seen as dirty a filter. I figured this was because the previous owner hadn't changed it, and I was a year in to ownership. At any rate… just 1 month and 10 engine hours into the new filters, the engine died at sea and I had to emergency anchor and then get towed into my slip.

On inspection, the port side Racor filter was black and coated with a bit of dark sludge. I have a 2”” inspection port at the top, and was able to take a photo inside the tank.

See photos below.

I replaced the filter myself, in an attempt to simply get the engine running, but the engine still won’t start.

It’s very likely that I didn’t bleed the engine correctly, or perhaps the sludge has gummed up the primary filter (which I haven’t changed), or the fuel injectors (please, Lord, no!).

My knowledge of bleeding the engine is strictly from researching online posts. I know enough to be dangerous, and it seems like a real chore. I was able to bleed the top fitting on the primary engine filter, and the fuel injector fittings themselves. I was NOT able to bleed the fitting at the top of the governor, as for the life of me I could not fit a wrench or socket into that small a space.

At any rate — my thoughts are to figure out or hire someone to properly bleed the engine, with new filters all around, just to get her running again… and then to immediately determine the scope of issues in the tank.

The tank is 57 gallons and about 15% full. I believe my error was in not keeping the tanks topped up over the winter, and I assume some sort of moisture has entered in.

INSIDE THE TANK


CLEAN STARBOARD RACOR


DARK PORT SIDE RACOR


PORT RACOR FILTER W/ SLUDGE


So the question becomes paying someone to polish the fuel and clean the tanks, or trying to do the grunt work myself.

Would love any thoughts/advice from people who’ve gone through this process in the past, or might have a recommendation of a person, service, or yard here in the Pacific NW to help.

And on that note, I would ALSO really love to find "a guy" who knows Perkins 4108's and who I could pay to spend a few hours training me on engine basics (filters, oil change, bleeding the system, pencil zincs, other misc maintenance issues).

Thanks in advance,

Sean
1978 Cal 39 MkII S/V AIOLOS
Seattle, WA

Hello Sean,
I came across your post and felt I need to let you know of my experience with the same issues in my tanks. We had a good day on the water but the wind picked up when returning back port and my engine died in minutes. I had dual Racor 500’s like you and was able to get back to the dock but went through a case of filters to do it and things got real interesting close to the slip. I had about 20 knots of wind and a ton of full moon current to deal with. After this nightmare I went to school on fuel. As much as possible anyway. I sent a fuel sample off to a lab and specifically requested them to let me know how many ppm’s (parts per million) of algae was in my sample. The report cost me about $110.00 and it was very thorough. It showed that I had some water and lots of particulate or sludge some microbes/bugs but no algae. It seems Algae needs water and sunlight to grow and we certainly have no sunlight in the fuel tanks. We find algae in ponds and swimming pools like always. I had called the stuff in my filters algae all of my marine life and it appeared to be the most common term amongst us mariners. I had used Biobor for years. Long story short, I purchased a small portable fuel polishing system and cleaned the tanks myself and stopped using biocide as well and began using another additive to dissolve any sludge and prevent the formation of a worse problem in my tank. I now polish my fuel about once per month ever since and have not experienced the problem again. Hope this helps and good luck.

[LittleWing77]

Originally Posted by Lepke

If you use enough fuel to continually add new fuel, then the additives that kill bugs and stabilize the fuel stay current. But if your fuel goes many months without refueling, you need to add a fuel conditioner. The better ones kill organisms that live between the water and fuel, stabilize the fuel components, add lubrication, help the Racor remove water, minimize soot, and enhance combustion.
To clean the tank, you can add an electric pump that pulls thru the racor and returns at least 30-40 gph to the tank. The 4108 doesn't return enough abundance of fuel to get ahead of the debris. Whatever fuel conditioner you use, start with a triple dose.
I use Archoil AR6200 and never have fuel problems. I also get about 6+% better mileage with it. Available online at archoil.com, Amazon, eBay and better fuel suppliers.

Lepke is the man who KNOWS diesels on this Forum, Sean. Listen to his advice especially!

(Although everyone else's has been pretty darn helpful, too)

Good luck!
Warmly,
LittleWing77

[capt jgw]

Originally Posted by Stu Jackson

In addition to cleaning, you should also check if you have a ball style check valve on the INLET of your filter housings. I just learned about this the other day, as a result of forensics on a fuel starvation issue I had. After 33 years (!!! - imagine that!!!) there was a buildup of sediment, thick black gunk, that prevented the ball from operating and stopped fuel flow. I learned about this by reading the filter housing manual - RTFM. I removed the housing, opened the cap to the ball valve and cleaned it out.

Check valve could also be a stand alone unit in the fuel line, could be anywhere between the tank and first filter. It prevents the fuel from draining back to the tank when you open the line as in changing a filter. Handy if the tank is lower than the engine but unnecessary if the other way around.
If you can't get a wrench on the injector pump bleed screw, try the injectors themselves. Crack loose one of the nuts that holds the injector pipe to the injector nozzle. Cycle the lever on the lift pump if it has one, or crank the engine till solid fuel without bubbles comes out. Tighten the nut and move on to the next one. You may have to do this even if you did bleed the injector pump as there's still air in the pipes and it won't start till it's all gone.