Finding a Weird, Unknown Creature Living Inside My Fuel Tank
While I was sailing singlehanded from Channel Islands Harbor to Santa Cruz Island aboard my Bristol 299 sailboat, my trusty Yanmar diesel sputtered and died two miles from Scorpion Anchorage. “No problem,” I thought, while jumping to the engine room in moderately rough sea conditions to check filters and other possible obvious causes of the problem.
It soon became evident that the fuel line from the tank to the engine was plugged. It was getting late in the afternoon, and sailing back to CI Harbor and crossing shipping lanes in my exhausted state seemed a bad idea. So I took a tow back to my harbor.
The next day, I went for the jugular to trace my plumbing from the poly tank. Unfortunately, the tank’s fuel pickup tube proved impossible to remove without destroying the plastic fuel exit nipple on top, so I dropped that idea. Next, I started to remove the fuel hose that was connected to an elbow on the tank, and this move revealed something extremely shocking.
What is that wormlike “creature?” With limited study so far, including a reply from a UC biology department, I have not found a definitive, authoritative ID.
As a longtime cruiser, I know the importance of keeping fuel clean and free of contamination from critters that can live in diesel fuel and other petroleum products. For example, I have learned that small nematode worms are being used to digest and clean up petroleum spills — and to digest waste at treatment plants.
Very surprising. Could it be a nematode?
I routinely use diesel fuel conditioner, and I pump out fuel from the bottom of my tank to check for cloudiness, dirt and water. Result: crystal-clear fuel.
What is this creature/organism? And how could it survive to reach the size it had? Checking with fuel dock staff at CI Harbor, I’m told all fuel goes through a 5 micron filter. If you can assist with this ID process, I’m sure that many sailors and other boaters would be very interested.
I checked my ship’s logbook and found that I’d replaced the old aluminum fuel tank 30 years ago, after we returned from a voyage from S.F. to the Caribbean and the US East Coast. So whatever “it” is, it wasn’t picked up from fuel we got in travels through nine countries.
Let’s see if together we can come to some conclusions that might help us all to avoid this potential clog-up problem.
Rather than a “creature” it may be degraded sealant used in the tank or plumbing.
Wow, the creature looks quite alien. Glad you found the source of your fuel supply problem.
No idea but I want to know what you find out
Dear sirs, a conundrum that can be solved by your local Agriculture agent who would have it tested. If your imagination lets go, I see a snail carcass but I also see degraded sealant. Only a lab will tell for sure. Let me know please.
It is a diesel slug, their microscopic eggs ( less than one micron) travel in misty air and can be sucked up into your tank through the vent. They are from the age of dinosaurs and the eggs survive deep underground in the crude oil. Crude oil from one well is the best known source of the eggs. They have started to spread mostly in the marine small engine environment. Be careful how you handle it they have stingers in their tail.
Silicone sealer, probably put on threads at some point either in your system or the suppliers. Saw it many times on a 23 footer that previous owner used silicone on all the threaded fittings. I had to TOTALLY replace entire system to eliminate repeated visits from that “creature”.