Fuel for Thought, Epilogue

Note to the reader.  Again, just as with my last posting, this is one of the (even longer), “this is what I learned to today, everything you ever wanted to know about” blog posts.  For those less technically drawn, my next post will be about retrieving my smuggled pick-pocketed phone near the US-Mexican border.

San Diego Skyline at Dusk
San Diego’s peacock-colored skyline at dusk, as seen across from the Silver Gate Yacht Club at Shelter Island.

Long time, pre-college friend, Deren, having read my previous blog post, “Fuel for Thought,” got on a plane and flew from Seattle to San Diego to help me finish getting Kandu ready. With his help, we found the likely source of a clicking sound I’d heard when we came in from Oceanside: the alternator belt on the engine was loose and worn. We replaced it and the refrigerator air-conditioning compressor belt as well. With a little help from Bryce, Deren replaced the rechargeable batteries in the solar vents, while I determined that the wind generator had a faulty controller and arranged for a replacement. We tested the Honda generator, insuring it could properly charge our boat’s batteries. And we went sailing in San Diego Harbor, successfully testing the wind vane self-steering. With Deren’s help, we accomplished three days of work in one!!! I was elated. We celebrated with a Bali-Hai Restaurant cocktail (the strongest libation California law allows a bar to sell) and a spectacular view of a full-moon rising over a peacock-colored San Diego skyline.

Full Moon Rising over San Diego
Full Moon Rising over San Diego

The next day, with fish net in hand, we removed the inspection plate from Kandu’s largest fuel tank, the 90-gal center tank, located in the bilge. Following legend Tom’s advice (read blog post “Fuel for Thought, Part II”), I had marinated the fuel in bacteria sugars-eating elixir for 5 days.

11" cover plate.  The towels keep nuts from straying too far while removing.
11″ cover plate. The towels buffer nuts from straying too far while removing.

Lifting off the 11-inch diameter steel inspection plate cover, we immediately observed the rotted edges of the black neoprene gasket material that made the seal between the outside edge of the cover and the 8-inch diameter steel tank opening. Carefully we cut away the rotted gasket material from around the opening, insuring nothing fell into the tank. Once cleanly removed, it was time to perform Tom’s other recommended tasks: 1) determine whether the tank’s drawtubes had filters on the end, and if so, their condition, possibly removing and cleaning them, and 2) find and remove whatever material may be blocking the drawtube.

Long time friend, Deren, sporting two sets of eye glasses and an LED spotlight, helps me determine next steps.
Long time friend, Deren, sporting two sets of eye glasses and an LED spotlight, helps envision next steps.

Appreciating the importance of the tasks, I couldn’t leave success up to chance. I needed the best possible information I could afford. I also wanted to know whether I had a bunch of slimy tar-like sludge at the bottom of my tank, or slime growing on the sides of my tanks. Rather than blindly waving a fish net in hopes of capturing the offending articles, I decided to alleviate any doubt. From the outside face of the tank, I compare the depth of the tank against the length of my arm. The inspection plate is close enough to the aft-side of the tank and the bottom is shallow enough that my arm should easily reach the bottom of the drawtube. Removing my shirt, I reach the full length of my arm into the bowels of the tank. Fortunately for me, I don’t have the best sense of smell, so the Eau d’Diesel wasn’t bothering me so much. Besides, I find the newer diesel formula doesn’t smell as bad as the older stuff did.   Reaching down to the bottom of the 5/16” drawtube’s intake, all questions were answered. A quarter-sized piece of rubber is stuck to its end and I felt no filter. Feeling around further, I found and removed large pieces of rubber, making up what was likely the 8” center of the 11” gasket. It turns out that the gasket wasn’t a ring but rather a single circular piece. The center had dissolved and dropped to the bottom of the tank. Piece by slimy piece, I pulled the harmful segments from the tank’s bottom. The diesel had apparently swelled the rubber material. Most satisfyingly, the slimy texture seemed more a result of oily diesel having saturated the neoprene rubber than that of a bacterial coating. Better yet, I felt no slimy sludge at the tank’s bottom or sides or top, only some rust sediment which is too heavy and would be easily filtered even if it did get pulled up into the drawtube, nothing to worry about. I am relieved, . . . very relieved. Better to discover all this now, in the calm of San Diego Bay than later, in the rough of Mexico and the Pacific beyond.

My elation is clouded by disappointment, why had someone installed such a poor gasket material, something that could dissolve and slough off into the tank and block fuel flow? The tanks had been cleaned by a professional tank cleaner four and half years earlier in San Carlos, Mexico, a popular boating town on the eastern edge of the Sea of Cortez. Surely, as a professional, he knew what he was doing when he replaced the gaskets? Then it dawned on me: newer US diesel is formulated with biofuels and additives that don’t exist (or at least didn’t 4.5 years ago) in Mexico. The new diesel eats rubber. Aware now of the problem, we made a plan to replace all four inspection plate gaskets (the main/center tank has two inspection plates, the second is a square opening added after the factory). First, we had to determine with what material to replace the faulty gaskets. While I moved on to other tasks, Deren walked to vendors along Shelter Island Drive to determine the proper substance. Cork was one idea that I rejected immediately. Ten minutes later, Deren called with a recommendation of nitrile. After a couple of phone calls, I located a distributor in northern San Diego’s industrial park. They said nitrile was indeed impervious to diesel. Thank goodness Leslie wanted to keep our car until we left California! An hour later, I had a $20 roll of shiny black, stinky nitrile rubber on board.

Cutting diesel impervious nitrile into inspection plate gaskets for Kandu's fuel tanks at the Silver Gate Yacht Club guest dock.
Cutting diesel impervious nitrile into inspection plate gaskets for Kandu’s fuel tanks at the Silver Gate Yacht Club guest dock.

While Deren prepared the other tanks for the removal of their inspection plate covers, using the center tank’s plate as a cutting pattern, and the side tanks having the same size inspection plates, I went on the dock and used a utility knife to cut the rubber to shape. Inspection plate by inspection plate, we carefully removed the deteriorating gasket material and replaced it with fresh cut, 1/8” nitrile.

Deren prepares inspection plate removal from saddle tanks.
Deren prepares inspection plate removal from saddle tanks.

The center gasket material for the side (a.k.a. “saddle”) tanks had not yet fallen in. We were able to remove them intact. But the center section of the second, rectangular, inspection plate, the ‘after-market’ one installed as an after-thought on the forward part of the center tank, had been eaten away, just the rotted rubber outline remained. So, without hesitation, we prepared a bucket, I pulled off my shirt and confidently slipped my arm carefully through the opening and into the cool cavity of pinkish diesel. But unlike the other side of the tank, I found no rubber bits at the bottom of the tank. Each tank has baffles, metal walls of sheet metal welded in place to prevent the fuel from sloshing back and forth. Holes in the baffles allow fuel to flow more slowly toward the lowest part of the tank, where by means of the engine’s fuel pump, the drawtube, like a straw, sucks fuel into the engine’s injectors, after passing through four fuel filters. The baffle hole edges are sharp. I needed to be careful when I reached into them, searching around and behind the baffle walls with my fingers like a game of blind-man’s hide’n’seek. Still, I found nothing. I did it again, to be sure, and again, I found nothing. The tank has no slime, but no trace of the deteriorated rubber either. Then it came to me: I had pulled a lot of rubber out of that first inspection plate port. Maybe with all the movement, the rubber from this port had made its way past all the baffles to the lowest part of the tank and to the other port. But how could I be sure? I recalled that when a mother gives birth, to insure the entire placenta has been removed, OB GYN’s piece together on a side table all extracted placenta bits and make a complete placenta, thus confirming no pieces remain inside the mother. On the dock, I set down a large black plastic trash bag and pulled from the orange 5-gallon plastic bucket the pieces we had collected. I set aside the saddle tanks’ gaskets, as they were intact. Making space for the center tank’s gaskets, I first took the drier edge remnants of the circular port and butted them up to each other. Paying close attention to how the edges lined up, careful to match their patterns, I made a ring. But the center circular section of the gasket was larger than the outer ring, presumably because it had swelled with diesel and slept on the bottom. Still I was able to piece most of it together.   There were plenty of rubber pieces left to make up another gasket puzzle. I laid out the dry outer edge of the rectangular inspection plate gasket. The inside pieces dwarfed the outline, so I pieced the interior puzzle adjacent to it. It was a near perfect match and I was satisfied that we have recovered everything from the rectangular port. Only a nickel-sized strip was missing from the circular gasket. Either we weren’t so careful to toss all the extracted pieces into the bucket, or there’s still a piece of rubber floating somewhere behind a center tank’s baffle, large enough to plug the center tank’s drawtube. Solution? 1) Draw the fuel from the saddle tanks first. 2) Using the fuel polishing system, pull and filter fuel from the center tank into the emptied saddle tank. 3) Should the polisher’s fuel pump get held up by the orphaned piece, or once we get to a calm anchorage in a couple of months, I’ll reach in again and feel around for the rascal. In the meantime, because the saddle tanks sit higher than the engine’s fuel pump, it’s better to draw fuel from them, taking advantage of gravity to feed the engine than to draw from a tank that sits lower than the engine’s fuel pump, making it work harder.

Among the many tasks Deren completed, adding two emergency backstays was one.
Among the many tasks Deren completed in three days, adding two emergency backstays was one.

And so ends the mystery of Kandu’s fuel problem: time was devoted, knowledge was gained, and only a little money spent—a more-than-fair trade. The next day with Deren was as equally productive as were the first two, eliminating nearly all my hardware tasks. His was a gift well received.  For the first time in two and half years, I woke up without a significant to-do list pointed at my head. The Bali-Hai Mai-Tai didn’t hurt either.

Imbibe at your own risk . . . you've been duly warned!
Imbibe at our own risk . . . we’d been duly warned!

Eric Rigney

Leave a Reply

Your email address will not be published. Required fields are marked *