Racor Diesel Fuel Filters

45Gunner

45Gunner

Active Member
Sep 22, 2019
191
Boynton Beach, FL
Boat Info
2000 460 Sundancer. Garmin 8612 XSV, GHC 20 Autopilot, GMI 20, 215 VHF, GC 12, Fantom Radar.
Engines
Twin 450 Diamond Series 6CTA 8.3M Cummins.
I purchased a 2000 SeaRay 460DA back in December. In April my mechanic and I set out to set up a baseline for future maintenance. We changed nearly every hose in the Cummins and Westerbeke. All new oil and fuel filters along with zincs. You get the picture. The last item on the list was to change out the filters in the Racors (4). Turns out we discovered the filters were full of what my mechanic referred to as snot...a black, ugly mess. When the filters came out we wondered how the engines were never fuel starved. Once out, I made the decision to rebuild all the Racors since two of them were showing air bubbles.

I have been very careful about putting additive into my fuel tanks each time I fuel up. The Racors had a service date written on them as 10/2019. The question is can bacteria grow that fast or was the 10/2019 service date put there just to show updated service?
 
45Gunner, there is a very seasoned diesel Sea Ray owner here, FWebster, who took the time to put together a diesel fuel management program document that is worth it's weight in gold. It tells you what to do in your situation to clear it up, and what to do to keep it right. If you sign up for a sponsorship that document and access to a bunch of other info is available. I highly recommend it.
 
If they put new filters in, but didn't clean the black gunk, it would stay there. You did right in cleaning/rebuilding and following Frank W's recommendations - esp on the Biobar...
 
While an unscrupulous owner or mechanic could have just written a date on a service tag, I think unlikely..they didnt know when the boat might sell, likely at least maintaining the filters. Possiblly got some contaminated fuel, but the ingredients for this are moisture and warmer temps. Moisture is always getting in via the tank vents and that's enough to feed the bugs if fuel untreated or left long enough.
 
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carterchapman said:
Question - did you use a "shock" quantity of the biocide additive?
Click to expand...
At the suggestion of my mechanic. When this weather finally breaks, I'm going to run the boat out to the ocean and make it rock and roll....stir up the fuel. An examination of the fuel filters will follow that. If clogged up with black gunk, it may be time to have the tanks polished.
 
45Gunner said:
At the suggestion of my mechanic. When this weather finally breaks, I'm going to run the boat out to the ocean and make it rock and roll....stir up the fuel. An examination of the fuel filters will follow that. If clogged up with black gunk, it may be time to have the tanks polished.
Click to expand...

I had some 'gunk" in my tanks when I purchased. I used Clear Diesel from Power Services to disperse what was in my tanks (wasnt very much), and then ran Frank's recipe from there. Cleaned things up nicely, and my fuel is spotless to this day.

Before you head out into open water, change your generator filter and run your generator at full load for a couple hours. A diesel engine circulate a much larger amount of fuel back to the tanks than it consumes, so sludge will show up in the genny racor first. You should be able to get an idea how much sludge your dealing with and come up with a plan before exiting the inlet.

If there isnt a lot of sludge in your generator racor, you may not have a huge problem. Treat with Clear Diesel to get rid of the slime and water in the existing tanks. Burn it down as far as you dare, then refill using Franks formula.

If you do head out into open water make sure you have about 1/2 dozen filters for each filter base and I'd say at least 4 on engine filters before heading out. You will be "polishing the tanks" and using the racor/on engine filters to accomplish it. Nothing wrong with this approach, you just don't want to get clogged filters and not be able to get home if the amount of slime in your system overwhelms your filter system.
 
Last edited:
dtfeld said:
I had some 'gunk" in my tanks when I purchased. I used Clear Diesel from Power Services to disperse what was in my tanks (wasnt very much), and then ran Frank's recipe from there. Cleaned things up nicely, and my fuel is spotless to this day.

Before you head out into open water, change your generator filter and run your generator at full load for a couple hours. A diesel engine circulate a much larger amount of fuel back to the tanks that it consumes, so sludge will show up in the genny racor first. You should be able to get an idea how much sludge your dealing with and come up with a plan before exiting the inlet.

If there isnt a lot of sludge in your generator racor, you may not have a huge problem. Treat with Clear Diesel to get rid of the slime and water in the existing tanks. Burn it down as far as you dare, then refill using Franks formula.

If you do head out into open water make sure you have about 1/2 dozen filters for each filter base and I'd say at least 4 on engine filters before heading out. You will be "polishing the tanks" and using the racor/on engine filters to do accomplish it. Nothing wrong with this approach, you just don't want to get clogged filters and not be able to get home if the amount of slime in your system overwhelms your filter system.
Click to expand...

I had this exact same issue when I purchased. Removed and cleaned up the Racors units, treated the fuel, and no problem since. I always have treated my fuel very similar to what Frank recommends, and have since changed to his full "recipe".

Any water in the Racors? Either way, check your fuel cap o-rings. Really common place for water to enter the tanks.
 
Just get a couple of good long 1 hour runs on her in the ocean and all of your fuel will have passed through those filters via both burn and bypass. So you are actually polishing while your run. Change out the filters and keep the additive up on any new fuel added. My guy swears by the valve-tech biocide additive. I dealt with this once when I moved to FL and never had the issue again. I change out my racors 2 or 3 times a year, cheap price to pay for clean diesel.
 
If there is bacteria, the biocide will kill it and your filters will be black rather than pink, but there should be no sludge. Once your filters are pink at change, you have killed everything in the tank. My genny recirculates over 30 gph, and I have switched to a 10 micron filter since it is a polisher as well (as DTFeld mentioned). CAT calls for 30 micron primaries, but MAN calls for 10, so I switched the genny to 10 as well...
 
If you are seeing black stringy stuff building up in the Racor Turbine filter then you have a rather serious situation going on in the fuel tank(s). Trust me I know from what I inherited in my last boat. It will end with plugging up the fuel dip tubes in the tanks. The first thing is to shock the fuel with a biocide; I use BioBor JF as both for shock and maintenance.
The algae (that black stringy stuff) forms between water and diesel fuel so, as a side, you also have water sitting in the fuel tank. The first thing is to kill the algae with a shock treatment of a biocide; I used a 5X treatment of Biobor JF and that really knocked it down. You may need to polish which I also did to keep from constantly plugging up the Racor filters. Then follow Frank Webster's witches brew to both keep the fuel in good shape, control the water, and provide needed additions for the engines.
Tom
 
Not saying I agree but see below post from Tony Athens at sbmar.com...

Good filtration before the engine = no additives needed for #2 diesel that has just been sitting for few years.

Tony Athens
Seaboard Founder
 
That maybe true on the West Coast where Seaboard is located, but in most other coastal areas, particularly in the South, there is enough moisture in the air to cause condensation to form in fuel storage tanks so I'm not storing fuel for years with no treatment.

As to how the OP found himself with a fuel mess almost immediately after a clean-up.......2 of the sources of diesel contaminents I listed in the fuel article was accidental introduction of water into the fuel from wash water or rain run-off. (dry-rotted o-rings on fuel fill caps) Water in diesel fuel really accelerates microbial growth. The other source, and the one most likely in this caase is the introduction of sludge in the vessel's tanks in the fuel pumped into the boat at the fuel retail point of sale. The fuel you buy at your marina is transferred from tank to tank several times before it gets to your boat. Every tank can have water/sludge/dirt in it and you can easily get a load of it when you buy your fuel.

To avoid that risk, always buy your fuel from a pump that has a filter on the pump right before the hose going to the nozzle. Look for a date written on the filter indicating the last change.

ValveTech biocide is a good product; however, I don't use their general fuel additive because they will not publish what it does to cetane, lubricity, or cold weather performance. Both Stanadyne and Power Service Products publish what their products do to your fuel and the fact that you cannot over treat with either product family.

And, 45Gunner, if you will read the Diesel Fuel Management article, near the end there is a procedure for cleaning up a fuel mess that involves just Power Service additives. Their Diesel 9-1-1 is now marketed as a cold weather product, but it also has the characteristic of being able to break up the clumps or strings of microbial growth into small enough particles that it can pass through normal diesel filters without clogging then up. Using a shock quantity of a biocide + Diesel 9-1-1 may cost you a few Racors but it will be a lot cheaper than having a fuel polisher come to the boat and polish your tanks.

Good luck with it........


Frank
 
fwebster said:
Using a shock quantity of a biocide + Diesel 9-1-1 may cost you a few Racors but it will be a lot cheaper than having a fuel polisher come to the boat and polish your tanks.
Click to expand...
Or worse yet, have to cut the tanks open.....
 
fwebster said:
That maybe true on the West Coast where Seaboard is located, but in most other coastal areas, particularly in the South, there is enough moisture in the air to cause condensation to form in fuel storage tanks so I'm not storing fuel for years with no treatment.

As to how the OP found himself with a fuel mess almost immediately after a clean-up.......2 of the sources of diesel contaminents I listed in the fuel article was accidental introduction of water into the fuel from wash water or rain run-off. (dry-rotted o-rings on fuel fill caps) Water in diesel fuel really accelerates microbial growth. The other source, and the one most likely in this caase is the introduction of sludge in the vessel's tanks in the fuel pumped into the boat at the fuel retail point of sale. The fuel you buy at your marina is transferred from tank to tank several times before it gets to your boat. Every tank can have water/sludge/dirt in it and you can easily get a load of it when you buy your fuel.

To avoid that risk, always buy your fuel from a pump that has a filter on the pump right before the hose going to the nozzle. Look for a date written on the filter indicating the last change.

ValveTech biocide is a good product; however, I don't use their general fuel additive because they will not publish what it does to cetane, lubricity, or cold weather performance. Both Stanadyne and Power Service Products publish what their products do to your fuel and the fact that you cannot over treat with either product family.

And, 45Gunner, if you will read the Diesel Fuel Management article, near the end there is a procedure for cleaning up a fuel mess that involves just Power Service additives. Their Diesel 9-1-1 is now marketed as a cold weather product, but it also has the characteristic of being able to break up the clumps or strings of microbial growth into small enough particles that it can pass through normal diesel filters without clogging then up. Using a shock quantity of a biocide + Diesel 9-1-1 may cost you a few Racors but it will be a lot cheaper than having a fuel polisher come to the boat and polish your tanks.

Good luck with it........


Frank
Click to expand...
fwebster said:
That maybe true on the West Coast where Seaboard is located, but in most other coastal areas, particularly in the South, there is enough moisture in the air to cause condensation to form in fuel storage tanks so I'm not storing fuel for years with no treatment.

As to how the OP found himself with a fuel mess almost immediately after a clean-up.......2 of the sources of diesel contaminents I listed in the fuel article was accidental introduction of water into the fuel from wash water or rain run-off. (dry-rotted o-rings on fuel fill caps) Water in diesel fuel really accelerates microbial growth. The other source, and the one most likely in this caase is the introduction of sludge in the vessel's tanks in the fuel pumped into the boat at the fuel retail point of sale. The fuel you buy at your marina is transferred from tank to tank several times before it gets to your boat. Every tank can have water/sludge/dirt in it and you can easily get a load of it when you buy your fuel.

To avoid that risk, always buy your fuel from a pump that has a filter on the pump right before the hose going to the nozzle. Look for a date written on the filter indicating the last change.

ValveTech biocide is a good product; however, I don't use their general fuel additive because they will not publish what it does to cetane, lubricity, or cold weather performance. Both Stanadyne and Power Service Products publish what their products do to your fuel and the fact that you cannot over treat with either product family.

And, 45Gunner, if you will read the Diesel Fuel Management article, near the end there is a procedure for cleaning up a fuel mess that involves just Power Service additives. Their Diesel 9-1-1 is now marketed as a cold weather product, but it also has the characteristic of being able to break up the clumps or strings of microbial growth into small enough particles that it can pass through normal diesel filters without clogging then up. Using a shock quantity of a biocide + Diesel 9-1-1 may cost you a few Racors but it will be a lot cheaper than having a fuel polisher come to the boat and polish your tanks.

Good luck with it........


Frank
Click to expand...
Indeed I followed the recipe that FWebster put out and have had success. I am schocking the fuel every three months and then changing the Racors until it remains pink continually. I have not had any fuel/engine issues. Got a long trip planned and will be running the ocean and giving the generator a workout while at anchor. I did change the gaskets around the fuel filler caps and it seems to have made a difference also. Thank you everyone for your input.
 
Gunner,
You are on the right path. With you first leg to Elliot key by the time you get there if you run outside you will have cycled your fuel through the racors 3x. Change them there again and you should have a pretty clean tank. You will be taking on fuel a few times over your journey and your tank should be fully flushed out multiple times to ge the muck out. With the price of diesel so cheap right now ($1.85 a gallon today I paid) your best bet is to run your boat.
 
ttmott said:
If you are seeing black stringy stuff building up in the Racor Turbine filter then you have a rather serious situation going on in the fuel tank(s). Trust me I know from what I inherited in my last boat. It will end with plugging up the fuel dip tubes in the tanks. The first thing is to shock the fuel with a biocide; I use BioBor JF as both for shock and maintenance.
The algae (that black stringy stuff) forms between water and diesel fuel so, as a side, you also have water sitting in the fuel tank. The first thing is to kill the algae with a shock treatment of a biocide; I used a 5X treatment of Biobor JF and that really knocked it down. You may need to polish which I also did to keep from constantly plugging up the Racor filters. Then follow Frank Webster's witches brew to both keep the fuel in good shape, control the water, and provide needed additions for the engines.
Tom
Click to expand...
I think I am battling this now with the fuel pickup lines. I just bought the boat, previous owner said there was a gremlin with the generator causing a voltage spike. 2 company's have came out and looked at the genset while at the slip and said it operates as designed and there are no issues. P/O said that when he would go out in waves or rougher water is when there was an issue. I have let the genset run for a few hrs at the slip on full load with no issues...until sunday. Sunday I put 128 gallons in the center tank ( 510 DA with In/Op Fuel Gauge ) and she started to spit out the side so I knew it was full. 30 min later the Genny was hunting and then I think it was able to finally get the fuel it wanted and it oversped/spiked and shut down. I went out the next day and changed the filters and filled housings with new fuel and it ran fine... However I can see there is slimly string in the lower portion of the turbine housing. What symptoms did you have? Sorry for the exhausting post
 
So I was fortunate enough not to have biologic issues with any of my diesel fuel systems but when I bought the 58 all of the Racors had black particulate matter throughout. I had it analyzed and the results indicated Asphaltenes. I had all 5 Racors removed, cleaned and rebuilt with no reoccurrence. Not sure if that's what some of you are seeing or if you have Biologic AND Asphaltene issues.
 
Your generator siphon tubes don't go to the bottom of the fuel tanks; about 3/4 of the way down.
If you are seeing black stringy stuff in the generator's Racor filter it must be bad.
Rough seas will stir up anything on the tank bottom especially if the tank is below half full. But, I would have thought a problem would crop up with the main engine filters before the generator's.
So if it is that bad you have quite a bit of water in the bottom of the tanks that needs to be absorbed and removed.
At this point I'd shock the crap of it with Standyne Diesel Fuel Additive and Biobor JF. Have lots of filters on hand because a lot of the stuff will go into suspension. You may have to shock treat a couple of tank fulls and may have to blow back on the fuel lines with compressed air to the tanks.
@fwebster Frank may have additional recommendations.
Then when it is all cleaned up get some rebuild kits for the Racor filters and clean those up.
 
On my boat, all the dip tubes are the same length. Gen is no different then the mains.
 
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