The Blue View - Keeping Bugs Out of the Fuel

Fifteen years ago, when Marcie and I first started cruising, we met Doug and his wife Fay, aboard his sailboat, Nip and Tuck. Doug is probably the most laid back guy I know, and possesses an immense amount of knowledge about fuels, engines and boats in general. We immediately became fast friends, and we've connected in half a dozen exotic places around the world.

He lives in Florida now, and spent some time with us aboard Nine of Cups while were in St. Augustine. We had an opportunity to get caught up and talk about a host of subjects. One of our topics was the new low sulfur diesel fuels and its effect on marine engines. I asked whether he would be interested in doing a guest blog for us on the subject, and he graciously agreed. Here it is:

Just over a decade ago, the soot produced by the combustion of diesel fuel was one of the largest contributors to air pollution in the U.S. In 2006, in an effort to improve air quality, the government mandated reduction of sulfur in diesel fuel and petroleum refiners geared up to produce ULSD (Ultra Low Sulphur Diesel). ULSD fuel has less than 15 ppm (parts per million) sulfur as compared to 500 ppm sulfur of the previous diesel. ULSD was introduced slowly and by 2014, it was the only diesel fuel available to us in the USA. ULSD, in a nutshell, is a cleaner diesel fuel. There is little argument that the fuel available today reduces exhaust emissions and dramatically improves air quality. (As a side note, marine and off-road diesel fuel, as well as heating oil are all ULSD, and is dyed red.)

The new fuel has a few negatives associated with it, however. To produce ULSD, a new process called hydrocracking was added to the refining of the fuel. During the hydrocracking process the demulsibility, i.e. the diesel fuel's ability to allow water to fall to the bottom of the tank, has been reduced, so there exists a situation where some water is encapsulated or entrained into the fuel. Also the natural lubricant quality of the sulfur has been greatly reduced which causes additional wear on injector pumps and injectors.

In addition, sulfur was also a natural biocide which helped reduce bacterial and fungal growth in diesel fuel. Many mariners do not realize that hydrocarbon-eating bacteria exist and flourish in a wet environment and can clog filters, shutting down your engine - usually at the most inopportune time. The bacteria thrive in tank bottom water, as well as condensate and feed on the fuel, leaving behind a very black, slippery effluent.

Marine diesel tanks are particularly susceptible to water and moisture contamination. Boats are often used seasonally, so diesel fuel sits in the tanks gathering moisture and condensation in what is already a very moist environment. Fuel tank vents, which are usually vented outside the hull, easily gather moisture as the diesel fuel expands and contracts with temperature changes. Air is forced out of the tank as the air gets warmer during the day and the fuel expands, then is drawn back in at night as the fuel cools and contracts. In addition, as the engine is running and fuel is being used, moist air is constantly being drawn into the tanks.

One other issue associated with ULSD is that hydrocracking refineries can now convert residual grades of crude, e.g. asphalt and #4 and #6 bunker fuels, into #2 diesel fuel used in boats, trucks and locomotives. This technology became necessary as the demand for #2 diesel fuel became higher than the available supply. The petroleum companies needed a way to produce more #2 diesel fuel and found it through hydrocracking. Unfortunately, there is asphalt fallout in the #2 diesel fuel that is called asphaltene. Asphaltene shows up in #2 diesel fuel at times and looks very similar to the black slippery effluent created by bio-contamination. The only way to differentiate between the two types of contamination is by testing.

Here are some suggestions for long term care and maintenance of diesel fuel and tanks.

1. Keep your diesel tanks full if possible. This reduces the air space in the tank where moisture can form.
2. Check deck fill pipes to insure the rubber “O” ring or gasket is in good condition. It does not hurt to apply Vasoline to the “O” ring or gasket to keep it pliable. Replace if cracked or hard.

3. Clean your tanks regularly to insure there is no water or sludge on the bottom for your pump to pick up and carry to filters. You can hire a service to do this or make your own fuel polishing system.
4. Check to see if you have a water separating system on your vessel. RACOR makes a great water separator/filter. Check the micron size of your filter. Finding a filter with a 5 to 10 micron absolute rating is best. Always keep extra filters on your vessel. Service your fuel system regularly. Some of the microscopic encapsulated or entrained water in ULSD will pass through a fuel filter, which is why tighter filtration is always better.
5. The primary issue today with ULSD is water. Using an additive to help reduce water in your fuel is very important. Power Service “Fuel Power” is a very good product that I have experience with and is readily available at most auto parts stores. There are a lot of products available that tout they are excellent. Read reviews and check them out before purchasing.
6. Test your diesel fuel annually to see if you have any microbial contamination. This is a simple process that anyone can do. I use “Liqui-Cult” test kits. They are inexpensive and will tell you if you have any “bugs” in your fuel. Liqui-Cult test kits are available from several sources on the internet.

7. If your fuel tests positive for microbial contamination, make sure any water in your tanks is removed. Treat your fuel with a biocide. Sta-Bil and BioBor are both good biocides. They are dual phase, meaning they work in water, as well as the fuel.

8. Some of the fuel purchased out of the USA is not filtered and can create an issue to a sailor in a foreign port. It is easy to pick up a small 12 volt pump and a filter housing so you can filter fuel carried in deck tanks or, with the right fittings, connect to the supplier's fuel hose and filter the fuel going into your tanks. It might slow down the fuel delivery process but I would rather do that than be sitting on the water somewhere with clogged fuel filters.

Prevention through active maintenance is always better than sitting with a dead engine waiting on a tow boat.

W. Douglas Grimm STLE CLS OMA-1 was formally an ASE mechanic and Hazmat Supervisor. He has spent more than four decades in the petroleum industry testing fuel and lubricants as well as managing a large tank cleaning crew – generally ensuring that the fuel tanks of his hundreds of corporate customers were tested and cleaned and any sediment was properly disposed of according to EPA regulations. He's also been a boat owner for 30 years doing all his own maintenance.

Doug can be contacted at Capt.grimsley@yahoo.com

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The Blue View - Finding DC Electrical Faults

Note: This blog is the condensed version of the article I wrote for Good Old Boat magazine in the June 2016 issue. For the complete version, visit their website at www.GoodOldBoat.com.

Introduction

The electrical wiring on the typical boat has a tough life. The combination of salt, water, copper wire and electricity inevitably leads to poor connections, faulty circuits and corrosion. With a little time and persistence, some basic tools and a plan of attack, it is usually not that difficult to ferret out and correct those pesky electrical problems.

Test Equipment

Some electrical problems can be found just by observation - a green, corroded terminal or a broken wire, for example, are usually easy to spot. Most electrical faults, however, will require at least a basic inventory of test equipment. The following is a list of test equipment ranging from the most basic to the more specialized.

Test Lamp

This is the most basic fault-finding tool. Connect one wire to ground and the probe tip to the circuit being tested, and if the bulb lights, there is a voltage present. A test lamp is a quick and easy tool to use and will help find blown fuses, broken wires or defective breakers. They typically cost a few dollars, or you can make your own by soldering wires to a bulb or bulb socket. If you buy one, make sure the test lamp is intended for DC circuits – most test lamps sold at hardware stores are designed for household AC circuits and won't light up when connected to 12 or 24 VDC.

Inexpensive Multimeters

For a few dollars more, typically between $10 and $35, you can purchase a basic multimeter, and no boat should be without one. A multimeter allows you not only to determine whether a voltage is present, but to quantify it as well, e.g. is the voltage at the positive power terminal of that flaky VHF 10.5 volts or 12.5 volts? It will also measure DC currents up to about 10 amps, and make resistance measurements.

High End Multimeters

The next step up is a multimeter with a DC current clamp. An inexpensive multimeter can measure small DC currents, but the multimeter must be in series with the circuit to do so. For example, if you want to measure the amount of current your refrigerator compressor is drawing, you must remove one of the power wires, then connect one lead of the meter to the wire and the other lead to the terminal. If the current is more than 10 amps, the internal fuse of the meter will blow. To measure the same current using a multimeter with a current clamp, all that is necessary is to clamp the current probes over one of the power wires and set the meter to measure DC current. The current clamp is very easy to use and will typically measure currents exceeding 400 amps – more than adequate for the circuits on a typical boat. The price for a multimeter with a DC current clamp ranges from about $40 to $250

Jumper Wires

I keep a cache of jumper wires of various lengths, each terminated with alligator clips. The shortest is about 6” long, while the longest is about 30'.

Finding and Correcting Faults

A basic DC circuit aboard a boat is shown in Figure 1. A wire leads from the battery's positive terminal, through some sort of circuit protection device, like a fuse or breaker, through a switch, and then on to the load, whether it be a lamp or a windlass. A return wire is used to complete the circuit from the load back to the negative distribution terminal, and then to the negative terminal of the battery.

In a normal circuit in good condition, when the circuit breaker is turned on and the switch is closed, current flows to the load and the lamp lights up.

If the lamp doesn't light or the windlass doesn't turn, I have a number of steps that I follow to determine the cause of the problem. Before diving in, however, I first think about any clues. Was something recently changed? A new circuit added or modified? Do some parts of the circuit work while others don't. I remember more than one instance where I modified a circuit to add some new gear and in the process, inadvertently disconnected something else. Often the newly introduced problem didn't become apparent until weeks later.

Next, I do a check for obvious problems. Is the breaker on? Are there any fuses in the circuit, and if so, are they blown? Are any of the connections corroded or questionable? Do the terminal blocks and splices look good?

If I haven't discovered the problem by now, I get out my trusty multimeter and jumper wires, and start checking voltages. A very likely place for the fault to occur is in the load itself … the bilge pump has pumped its last drop of water, the LED light has emitted its last photon or the windlass has hoisted its last foot of chain. I set the multimeter to DC volts and to the appropriate range. Once all the switches and breakers in the circuit are in the “On” position, I measure the voltage across the load as shown in Figure 2. If I measure a voltage close to the battery voltage, then the problem lies in the load.

If the problem lies elsewhere, I methodically work my way through the circuit until I find it. Figure 3 illustrates the same DC circuit with several test points added. My plan of attack is to check the voltage at each point until I find the fault.

Using jumpers as necessary, I attach the negative lead of the multimeter to the negative distribution terminal, (if your boat doesn't have one, connect the negative lead directly to the negative terminal of the house battery) and starting with Point A, check each voltage in the circuit. If I see a voltage close to the battery voltage at Point A, but not Point B, I know there is a problem with the breaker. If I see the correct voltage at Point B, but not Point C, I know the fault lies in the wiring between the breaker and the switch. I continue working my way through the circuit until I find the problem. The only point I shouldn't see a voltage is at Point G. If there is a voltage there, I know there is a break in the return wire.

Additional Tips

In a perfect world, the fault would be readily apparent. The switch is defective and there is no voltage at Point D, for example, or there is a voltage at Point D and not Point E, indicating a broken wire between the two. Many times, however, the problem is more difficult to figure out. Here are some additional tips that might help.

• There are many times when I can't access a particular point to measure the voltage. I sometimes use sewing needles to pierce the wire to make contact with the conductor, then connect it to the multimeter with a jumper wire. When I'm done making the measurement, I use silicone caulk to seal the hole.
• Many times a problem won't be apparent unless there is a substantial current flowing through the circuit. A windlass, for example, has a very high current draw. If the breaker or foot switch has dirty contacts, voltage measurements taken while the windlass is idle may all appear normal. The same measurements taken while the the windlass is energized may show a large difference in voltage. The same is true for any device with a large current draw – a refrigerator compressor, starter motor, autopilot drive, etc. Make sure you make the voltage measurements while the load device is energized. This may require the assistance of a helper on occasion.
• I don't look for just the presence or absence of a voltage. If I see 12.45 VDC at one point, and only 11.20VDC at the next, I know there is a significant voltage drop between the two points. The usual culprits are corroded terminals or wires, or dirty switch contacts. If it is a new installation, another possibility is that the conductors that are too small.

Good hunting!

The Blue View - How to Make a Rope Rug

A few years ago I did a blog on making a nautical rope rug, or in sailor's parlance, an ocean plaitt mat. As I was making my 50^th or so mat a couple of weeks ago, Marcie suggested doing it again as a video. It seemed like a good idea, so here is the video version.