Fuel delivery system

The fuel delivery system is how Im going to supply my main engine, generator and any other diesel fired device that might end up on the boat. This system is separate from the transfer system and is fed from one 200 gallon tank.

The delivery system is fairly simple although having quite a few valves. Basically, Im pulling fuel out of the 200 gallon day tank, through another Racor filter followed by a five port distribution manifold that directs fuel to either the main engine, generator or another device.

In case I have a problem with the Racor filter while under way, I installed a couple of " Ts " in line along with three valves, so I could quickly by pass the Racor filter without shutting down the main engine. I could then change the filter or do whatever was needed while leaving the main engine running. Once the problem with the filter was resolved, I then would bring the Racor back on line by moving the valves back into the filter mode.

Between the Racor and the distribution manifold, I added two more " Ts ", and three more valves so I could add a 12 volt pump to prime the main engine or generator. Both the main engine and generator have a manual primer pumps on them, but I wanted an in line electric pump to make priming the engines a quick process. If for some reason any engine looses its prime, all I have to do is close one valve, open two valves, turn on the electric pump, and crack the fuel intake line on the injection pump. Im just guessing now, but Id say I could prime either engine and have them back running in less than a minute with this set up. For me, this is an inexpensive set up that is easy to do while Im running pipe that could pay me huge dividends some time down the road.

Because Im using a manifold to feed multiple engines, I felt as if I should install check valves where the engine supply lines connect to the manifold. Im afraid that one engine could want to pull fuel from another engine, and start messing with robbing an engine of primed fuel, or causing air and headaches to enter the system.

Im waiting on the check valves to show up and Im looking into different fuel pumps for my electric lift pump I want to install. I left myself plenty of room to fit the lift pump between the valves and "Ts", but Im stopped on this system until my parts show up early in the week. Besides having shut off valves at the manifold, I need shut off valves right next to the main engine and generator. While it may seem like Im have too many valves on this system, I think that they will pay off big once I start having to service the engines and system.

Because of where I want to install the electric lift pump and and the type of pump I want, I held the 1/2" steel fuel line 1.25 inches off of the fuel tank. An added bonus of doing this is that I now have a nice grab rail running the starboard length of the engine room.

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Fuel tanks

I have four fuel tanks on board of my trawler. Given this first sentence seems to sum things up I could be getting off easy in regard to this post and leave it at that. But since Im a little on the long winded side of this world, and the fact that Im totally into all things steel boats, I feel as if I should elaborate a little on my fuel tanks.

The four fuel tanks on board are integral tanks meaning they are now part of the hull. The tanks are on the outboard sides of the hull in the engine room between station 9 @ 14. I am using the term station as this is how the prints describe frame locations, and these two locations are actually steel bulkheads. I framed the tanks using 1/4" plate. All the tanks have a baffle located @ 30" on center witch is also what the frame spacing is. The baffles have the corners clipped off of them and also have 2" holes in the center to let fuel flow freely between them. The baffles are welded on all four sides of the tank walls and by using the slug welding method I was able to weld the baffle to the tank top. All four tanks have a drain valve at the lowest point in the tank in case I ever have to empty the tanks completely.

I could not in good conscience build these four tanks without providing a way to get back inside of them if I ever have to. I added an inspection port between each baffle for future maintenance. The inspection covers are made of 3/8 plate and are attached to the tank by a 3/8 stud that is welded to the inside of the tank wall. The inspection ports are 12" in diameter and are in the front wall of the tank. Because of the size of the tanks, putting the inspection ports on the top of the tanks made no sense as it would serve little use due to the depth of the tank. Getting the inspection covers to pass the air test proved to be the most difficult part of building these tanks. Using fuel rated gasket material I cut a gasket for each cover and punched holes for the studs. I then used a fuel rated gasket sealant applied to the gasket to improve the seal of the gasket. Because I did not want to stretch my mounting studs I used a torque wrench to tighten the nuts to the correct torque for a 3/8 bolt. My first air test showed each stud to leak! Next I tried using a heavy thread sealant on the studs. My next air test showed the studs to leak! The problem was the weld holding the stud to the tank was not air tight and my 7 psi air test was leaking past this weld and then past the mounting nut. My solution to making the covers air tight was to mill a counter sink in each tank cover to accept an "O" ring for each stud. I milled the counter sink in the covers to a precise depth so that the washer under the nut would compress the fuel rated "O" ring and provide a seal once the nuts were torqued down. My next air test proved all the studs passed the 7 psi test. I spent another day or so finding pinhole leaks in the tanks and making weld repairs. The final air test was to have the tanks hold 7 psi for 24 hours.

My two forward tanks ( port and starboard) hold 200 gallons each. The two aft tanks ( port and starboard) hold 500 gallons each. I intend to use one of the forward 200 gallon tanks for running the main engine and generator and the other three tanks will be used for storage. Ill have to transfer fuel from the various tanks via an electric fuel transfer pump. Ill probably use this same pump to polish my fuel from time to time to keep it clean and keep the condensation water out of the fuel. The total fuel capacity on board will be around 14oo gallons. This 1400 gallons is more than what the boat was designed for so I contacted the architect who designed the boat and reviewed this with him. Hal Wittacre ( the naval architect) did some stability calculations and recommended adding more ballast to the boat.

Each tank has a pick up tube for fuel supply and return. These pick up tubes go to within 1" of the tank bottoms. There is a fill point for both port and starboard on the aft deck of the boat. A two inch steel pipe will be used as the fill tube, with a vent that leads back to the fill port. The fill ports on the tanks just dump into the the top of the tank but I want to change that and add a tube that goes to the tank bottom. Bringing the fill tube to the tank bottom is a better design element for fuel tanks and I will make this change.

The fuel management system is fairly complex and really needs its own post to get into the details. Once I start work on this part of the fuel system Ill add a fuel management post.

The tanks are shown in these pictures with a plywood cover. I did this so that I could protect them during construction. Plywood will also be the final cover as there are many things that will be attached to this plywood.

Conall

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Fuel system

This is going to be the first of a few posts relating to my fuel system. Im glad I did not bid building this system for someone as Im finding this job burning up a lot more time and material than I would have guessed.

The first order of business for building the fuel system were installing the fill pipes. I have four integral tanks in the engine room with a capacity between 1200 - 1300 gallons. I have one 200 gallon tank that I will use as a day tank. The day tank will supply the main engine and generator with fuel. On the aft deck of the boat Ill have two fill locations, one fill for the starboard tanks, and one fill for the port side tanks. Both the port side and starboard side fuel fill pipes have ball valves in line to direct fuel to either the forward or aft fuel tank on each side of the boat. When I want to fill the forward port tank, I close aft ball valve and open the forward valve. Likewise, when I want to fill the aft port tank, I close the forward ball valve, and open the aft valve. When the tanks are full, all the ball valves on all the fill lines are closed. The fill pipes are steel pipe, 2" sch. 40.

The tank vents are 1" steel pipe sch. 40 and will exit the boat with the fill pipes and terminate at the fill stations.

After the fill pipes were fabricated I turned my attention to the fuel transfer piping. With four tanks on board, and one of those tanks being used as my day tank, I have to be able to transfer fuel from any one tank to any tank I desire. In order to transfer fuel Ill utilize an electric pump with a manual pump as my back up. Each tank has a dedicated pick up tube that extends to about 1" above the tank bottom for the transfer system. I added a second pick up tube to each tank to give me the option on using the second pick up tube for feeding the machinery while still having a stand alone fuel transfer system. The fuel transfer system has a large Racor filter that will clean the fuel and separate any water in the fuel before the fuel goes to the day tank.

I wanted to get a decent flow rate out of my transfer system, and because I was a little nervous about friction loss in the transfer pipe, I used 3/4" sch. 40 steel pipe for the transfer system.

Im in the excavating business, and Im always calling to have underground utilities marked before I dig on a job site. The marking companies spray paint the location of the various utilities on the ground using the following colors: red for electric, blue for water, yellow for gas, orange for cable and phone, and green for fuel or oil related. Given I have to paint the pipe to protect it, I have chosen to paint all the fuel related parts in the engine room green.

There is a lot to the fuel system, and I feel as if I got a good start on my first week of working on it.

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Fuel system update fuel transfer

The fuel transfer system resides in the engine room on the port side of the boat against the aft water tight bulkhead. Ive put a huge dent in the amount of work building the transfer system, and there is enough of the system completed for me to blog about. I want to use JIC fuel fittings on the lines between the intake manifold, the filter, the pump and the distribution intake, so I have to wait until Tuesday to get the lines made. Once I run the wire for the disconnect switch and get those lines fabricated, Ill be able to pump fuel from tank to tank.

I have four fuel tanks on board for a total of between 1300 - 1400 gallons. Three of the tanks will be used for storage, and the fourth tank will be a 200 gallon "day" tank that will be used to feed the main engine and the 10kw generator. The fuel transfer system is completely independent from the fuel delivery system which feeds the machinery out of the 200 gallon day tank.

Every day we are traveling on the boat we will manage our fuel by transferring fuel from tank to tank and making sure the day tank is full. As the fuel is transferred it will be filtered through a 1000 series Racor filter that will also remove water. The fuel that leaves the day tank to feed the machinery, will again pass through another Racor filter before being filtered by the factory filters on the main engine and generator. I have a mechanical flow meter in the transfer system that will be the primary way we keep track of how much fuel we have left and how much we are using. Once I fill the tanks and have some sort of base line for tank capacities, well use a log book to track fuel usage along with a flow meter on the main engine and dip sticks for the tanks.

The transfer systems pump is a rotary vane pump driven by a 120 volt 1/2 hp motor. The motor is continuous duty rated motor so I dont have to worry about run time. The pump and motor can move 220 gallons per hour which exceed the 180 gallon flow rate of the 1000 series Racor filter. I dont know if I need to put a gate valve on the pump to choke it down or if the Racor will do that for me. The motor pulls about 7 amps, and Ill have it wired in to the inverter circuit so I don have to worry about having shore power or the generator running if I want to transfer fuel. The rotary vane pump is self priming and is pretty close to bullet proof. This is very long life pump made by Procon that should give me a long life of reliable service. If for some reason the pump or motor fails me, I have a manual pump plumbed into the system that will handle our fuel transfer needs. I got the idea of the manual pump from a careful builder doing a fine job on building their 55 footer. You can check out Peter and his families boat building blog here: building koloa . If the manual transfer pump fails me I can use one of the four drain valves and another type of manual pump to move fuel. If I dont feel like doing that, I can block the vents and carefully use my air compressor and a regulator to push fuel from tank to tank using the transfer manifolds.

When transferring fuel,the fuel is pulled for one of the four tanks via a four port manifold. After the fuel goes through the filter, pump, and flow meter it is then pushed through a distribution manifold with five valved ports. Depending on what combination of valves is opened is how the fuel will find its way to the desired tank. On the five valve distribution manifold, four valves are for directing fuel to any of the four tanks, and the fifth valve is used for pumping fuel to some place else. If I ever have to give fuel to a stranded boat or get fuel off of the boat for some other reason, the fifth valve will be the way to do it. I actually have a sixth port of the distribution manifold since I did not know from which end I was going to be feeding the manifold. I have the sixth port plugged. All the flexible fuel line Ive been using in the engine room is Coast Guard approved marine fuel hose.

This was a pretty involved project, but Im for sure on the tail end of it and will have it operational within a few days. If I were to do it all over again, I would have paid more attention to how I was going to run the piping while I was building the tanks. A plan would have been nice, but you know how that goes. Stainless steel pipe would have been another good thing, but since Im on a shoe string budget, painted steel pipe will have to do. All the piping has been air tested from the manifolds, through the tanks to the deck fills and vents. Ill probably put 30 gallons of fuel in the system and start moving fuel around to clean the tanks. The next part of the fuel system to build is the delivery system and returns for the main engine and generator. Ill be starting on the delivery system this week.

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Fuel transfer system complete

The fuel transfer system is complete, and I dont have to do any more work on it. Well, I guess a persons definition of "any more work" should be discussed over a beer sometime. I do have to decide which electrical circuit I am going to use and make that connection. I only have one circuit ran to the engine room so far ( lights) , but Im going to be installing some more circuits in the next week or so as I am beginning to do some design with Kevin Morin ( www.metalboatbuilding.org) on the electrical system.

I backed my service truck in to the shop and pumped 30 or so gallons of fuel into tank #4 . I temporarily wired a plug end on to the fuel pump transfer switch and once I made sure I had the correct valves open ( I need to label the tanks), I turned the pump on. It took a about a minute for the pump to pick up the fuel, but once the the fuel hit the flow meter the sound of the pump changed and the flow meter started clicking off tenths of gallons. It felt good to finally have a system up and running.

To make sure things were as they appeared, I checked the amperage draw on the pump. The pump is only pulling 5 amps, which is lower than its full load rating. I also ran the pump for five minutes to check the flow rate. The flow rate of the pump is just about 220 gallons per hour based on my five minute run time. The flow rate I measured is is exactly as advertised by the manufacturer. The 1000 series Racor filter is rated at 190 gallons per hour maximum flow, so I have to figure out what is happening with the measured flow rate of the pump and the maximum flow rate the filter is advertised as capable of. At a first glance, I would have figured that the filter can only physically allow 190 gallons per hour of flow through it given the micron size of the filter media. I might put in a call to Racor and ask their opinion. A gate valve would choke down the flow rate and give the pump some head to work against. Ive always felt that pumps live longer if they have some head to push against.

I want to install a vacuum gauge on the filter to monitor when it begins to clog. I think Ive seen Racors with a vacuum gauge in the "T" handle, and given how Ive plumbed things, that looks like a good option.

After I had ran the electric pump for a half hour or so, I closed a valve, and opened the two valves for the emergency manual transfer pump. I pumped about five gallons to see how it worked, and Im pleased to say it worked fine. I will say that whenever one of the kids makes it to ye ole shit list, they can meet me in the engine room to manually transfer a 100 gallons of fuel.

It really feels good to finally have a system up and running. Because I now have all the fuel pipe work completed, some of the smaller jobs will begin to fall in to place. I can now install the generator in its final resting spot vs rolling it around the engine room on 3/4" pvc pipe. Once the generator is set, I can finish the conduit run for my AC in the engine room, and so on and so on....

Now that I have fuel running through the tanks, I will continue on my schedule and build the fuel system for the main engine and generator. This is not nearly as complex or costly as the transfer system, so hopefully Ill have that up and running in a week. Ill fire the engine once I have all the fuel parts in place.

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