We mentioned that upon delivery, we found Nauticarazi to have clogged fuel lines. Of course, this didn’t become an issue until we were off-shore in bumpy waters off the coast of Huntington Beach on our maiden voyage. No worries, as a few nights in a marina and a temporary rerouting of the fuel lines with some hose got us home.
The Nauticat line of boats are generally motorsailors, with huge fuel tanks. The Nauticat 40, 43, and 52 were exceptions to the brand, built as sailing vessels with auxillary engines. Nauticarazi is a Nauticat 43. True to the brand, the vessel has huge fuel tanks – twin 100 gallon tanks to be exact. That’s an effective range of about 1500 nautical miles for this boat WITHOUT any sailing. That means we could leave San Diego and travel the whole coast of Baja Mexico without refueling. Much further if we sail most of the way. Carrying this much fuel on a sailboat is something I never heard of before.
The issue, then, became that there was a lot of fuel in the tanks that sat… and sat, and sat… you get the picture. We talked to the owners before the guy we bought it from (they are friends of ours and our boat brokers) and they never put fuel in the boat because it already had enough. We are positive the guy we bought the boat from never put fuel in it, so we estimate the fuel to be over seven years old.
Seven years, sitting…
The issue is diesel fuel in a marine environment gets the equivalent of flu. The combination of excessive moisture and untreated fuel made for a perfect environment for a bacterial explosion that went unchecked for years. It didn’t turn up during the survey because we were out in relatively calm conditions. As soon as we left in some rocky weather… BOOM. The sludge in the tanks got sucked up, the fuel lines became clogged, and the engine shut down due to fuel starvation.
The Nauticat fuel lines are all copper tubing. It was easy to clear the clog and run a temporary fuel line to get us home. But that was only a temporary fix.
Nauticats have two pickups in each tank (three in the port tank – the extra for the heater). One is shallower and plumbs through filters to the engine. The other is deeper (almost the bottom) to suck out water, contaminants, and other crud that settles to the bottom of the tank. The idea is you can pump out the crud on the bottom, while the engine takes fuel from a safer, slightly shallower part of the tank. Great idea, if you use the hand pump to remove the bottom crud. No one had done that and the deep pickup and line was completely impacted with crud.
My initial goal was to install a separate filter and a fuel circulating pump on the deep line to build my own fuel “polishing” system that would filter out the crap and return clean fuel to the tank. I used a Carter vane pump (inexpensive on Amazon) and some valves and tubing from a hardware store to modify the original set up. Only problem was I couldn’t draw anything through these lines. I had to use high pressure air from a small, cheap air compressor to clear them. But as soon as I did, they would just become clogged again.
At this point, I’m really excited to spend even more money on this, so we scheduled with Ventura Harbor Marina and Yacht Yard to use their industrial fuel polishing gear to filter all our fuel. I went over to their dock and we began pumping fuel out of the tanks, but even their heavy-duty gear became clogged if I put their suction hose too close to the bottom. We “ran shallow” and removed all the fuel from the tanks to find the real culperate.
In the bottom of the tanks, we discovered a thick sludge the consistency of molasses. It looked like cake batter. It was disgusting. The yard determined they were unable to help me, but one of the guys had a great suggestion of getting a “burner” shop vacuum that I could use just once to suck all the sludge out of the tanks and throw away after. It sounded like a solid plan, and I had such a shop vac already, so I returned to our slip and got ready to get dirty.
The next day, Sanaz and I began clearing the tanks of all the sludge and slime we could. It was actually easier than we thought as the sludge was quite resilient and stuck to itself. Since it was covered in diesel, it made it slippery. All we needed to do was to get it started into the vacuum hose and it sort of pulled itself out of all the nooks and crannies in the bottom. After a few minutes, all the sludge was gone. Then, we pumped all the fuel from the other tank into this one and repeated the process on the other side.
I am happy to report the process worked. After a few rounds of blowing clear the lines, my fuel polishing system began to work. We treated fresh fuel with a biocide to kill off the bacteria that remained. We’ve been circulating fuel weekly for about a month now and every time the whole system improves. While the tanks aren’t exactly “clean”, they do get better each time we take on fresh fuel, treat it, and polish it. Last we looked at an empty tank there was a remarkable difference. Progress has been made.
Unfortunately the sludge also ruined one of the fuel level senders and left one working, but unreliable. Of course, they don’t make those anymore (i.e. we spend more money), so that has turned into a long issue with a recent resolution — I discovered an adapter plate from a pre-1959 Ford that will adapt the old sender mount to a new one, so we will soon know how much fuel is in our tanks at all times.
This is a process. I never said this boat thing was easy. Just said it’s always worth it.
Here’s some photos for reference. Try not to gag.
– Steve