What is this crap in my RACOR fuel filter ?

[a64pilot]

Your going to have to bleed most likely.
To get fuel to drain, you have to let air in, it won’t unless air goes back in to replace the drained fuel, then you have air in the system.

I had nothing but trouble with that little filter on my generator, replaced it with a Racor 500 and put the small filter on my outboard.
The filter elements were both harder to find and more expensive that the cartridges for a Racor 500. So be sure if your cruising that you have several. Maybe overkill, but I try to keep a dozen on board, if you ever get a load of bad fuel, then you can go through quite a lot of them.

[thinwater]

Xxhat: What fuel additive do you use, if any?

[Qayaq]

Looks like aluminium corrosion to me, possibly from previous water in the tank, possibly from alluminium reaction to fuel bug killer. Looks like a good opportunity to learn how to change the filter and bleed the system. Can you get a look inside the tank with a torch to see how much of that crud is in there, if its a lot you might be pleased that you are now comfortable with your ability to change the filter.

[elcappytan]

A good habit to get into is use a fuel strainer every time you fuel up. That crap looks like the rust inside a fuel storage tank. West marine sells one that will also show you if there's any water in your incoming fuel. Cheap insurance and take's a little longer when your fueling up but worth it.

[ArmyDaveNY]

Your question about what to do depends to an extent upon where you are and what your itinerary is. If you are in a location with good facilities and are not planning on passage making soon, then you can try a more graduated approach. If the initial actions don't solve the problem at least you are close to "home" and can get towed back in a worst case situation.

If you are planning a trip soon I would take more thorough actions, e.g. drain the bowl, change the filter, polish, clean the tank and lines, etc.

In all cases I would purchase several spare filters. Good luck with it!

[Taipe]

We may have had a thread last year with light brown, grainy sediment in an aluminum tank. If I recall correctly, by process of elimination, it disappeared when changing to a different diesel fuel additive.

In most cases, assume that water vapor condensation favoring the growth of fungi is involved in one way or another. Fungi are smart little buggers in the way they can figure out how to digest almost anything as their food. So for prevention, keeping the tank full to purge the humid air out is rule number one. And another way water can enter the tank is when sea water finds its way into the breather outlet that boat manufacturers for some reason feel it's necessary to locate on the outside of a cabin structure on deck. The solution to this is to relocate this passive vent to an area inside the boat as high up as possible (definitely higher than the fill tube) with a double loop at the upper end and someone to keep a sharp eye on it when the tank is being filled. Attaching a sink faucet aerator with a copper mesh end to this breather works well to let air in and out of the tank.

[sanibel sailor]

At least on my set up, air in the racor gets cleared as the engine filter fills with returned fuel. I still always fill the racor. The 200 size (now obsolete) is a good alternative to the 500. Our little engines generally do not move enough fuel to take much advantage of the turbo spin water separation effect.

DO NOT vent inside boat. A P trap solves solid water probs

[belizesailor]

Just cleaned similar crud from inside my Racor 500's water separator bowl. Fuel coming from tank runs clear, but there was about a teaspoon of this gunk in the bowl. Happiness is a big filter!

[thinwater]

Originally Posted by Qayaq

Looks like aluminium corrosion to me, possibly from previous water in the tank, possibly from alluminium reaction to fuel bug killer. Looks like a good opportunity to learn how to change the filter and bleed the system. Can you get a look inside the tank with a torch to see how much of that crud is in there, if its a lot you might be pleased that you are now comfortable with your ability to change the filter.

Snicker...."Can you get a look inside the tank with a torch...?"


This is primarily a US forum, and here torch means fire.


I am inclined to agree that looks like aluminum corrosion; if it is slightly gritty that would convince me. There are some additives that are very effective against aluminum corrosion.

https://www.practical-sailor.com/iss...s_11083-1.html



And for you trivia fans, aluminum is the ONLY element that has two correct IUPAC spellings.

[jooa]

Last fall I had diesel bug in my 40 year aluminum fuel tank. As my tank is only 40 litres and not too difficult to remove, I took it out to give it a proper cleaning. I also decided to cut an access port into the tank so cleaning in the future would be easier. After cutting the access port I discovered there was a lightish coloured sandy deposits on the bottom of the tank. I gave them a scrub and they came off as crunchy bits, looking very much like what appears to be in your filter. End result was I had to replace the tank because I could see that some of the pit corrosion spots appeared to be about 1/16th inch or so deep into the 1/8th inch aluminum tank wall.

If you are able to get a hold of a mini inspection camera, the type on the end of a cable, you could empty out your tank and see if the camera reveals anything. My friend owned one of these cameras and was eager to put it to use. It did not necessarily show me any corrosion but it did reveal that the tank had sludge on the bottom and a cleaning of both the tank and fuel would be a good idea.

Depending on how much fuel is in your tank, you could try run it down as low as possible, pump out the little remaining fuel and recycle it. Simpler than trying to polish it. Also has you ready to clean the tank.
Good luck!

[a64pilot]

Aluminum corrosion that I have seen is usually white or grey in color, and extremely “gritty” aluminum oxide is I believe what a lot of sandpaper is made from.

I love how Brit’s pronounce aluminum.
It was early 70’s and I was listening to a Brit salesperson explaining why JBL speakers were superior to the competition, it took him several times telling me about the aluminum frame for it to click that he was saying aluminum

[Dooglas]

I agree with JPA Cate - whatever it is, it's time for a fuel polish - as well as cleaning/replacing the fuel filter.

[Dooglas]

Originally Posted by a64pilot

I love how Brit’s pronounce aluminum.

No you don't. You love how Brits pronounce aluminium.

[bigreelsc]

I had what looked to me to be clean fuel in my Racor bowls. My engine guy pulled out what looked to be a cross between a kelp forest and a spinach farm. We use Biobar and such but that's why we use filters.

[casual]

Bio sludge, have seem it before. Or filter is coming apart inside .