I really love the Lister -- plodding along at 750 revs, it's more or less bulletproof, dependable, belt and braces (belt and suspenders over here) with three cooling systems, two lubrication systems, easy to work on, a great engine, and it hurt me to take it out.
However, it has its negatives -- you have to go down to the engine room to start it and it has oil cups slopping oil around. Both of these problems can be fixed, but the remainder are harder. Like the GMC two-cycle diesels there were so many of them produced that parts will always be available, they're not getting any cheaper -- one of Fintry's sister ships paid 3,000 Euros for a starter recently. In the USA, where we expect to sell the boat in fifteen years (God willing), no one has ever heard of a Lister. It's big -- height and width are not a problem, but it's very long and has a bunch of auxiliaries that take space. Most important, it's a hard mounted four cylinder engine and the vibration is always with you -- when we took Ilchester around Scotland, there was always something vibrating.
The Cat 3406 is great. The first time we took Fintry out after the Cat was installed, I accelerated out of the inner harbor at Portland, to about 1500 RPM and the boat was smooth as silk -- I thought we were doing around six knots. I looked at the GPS and we were doing nine. The soft mounts are so good that you feel no vibration at all when you put your hand on the bottom of the engine mount.
The 3406 is available at horsepower ratings starting at 360 and going up to over double that -- I saw a pair rated at 700 horse in a UK government fishing patrol boat at the SeaWork show in Portsmouth. While certainly the Lister is the gold standard for dependability, the Cat purrs along at around 1350 RPM to produce eight knots, putting out about 150 horsepower. I can't believe that for practical purposes it won't be just as reliable as the Lister.
The Cat is close to being a drop in -- the engine mounts sit easily on the existing rails and the height is appropriate for the shaft, assuming you use two constant velocity joints in an intermediate shaft to allow soft mounting the Cat. The only serious fabrication required is the mount for the thrust bearing at the end of the original shaft (without CV joints, the original setup took the propeller thrust on the gearbox. The CV joints canít take the thrust, so you have to install a thrust bearing between them and the shaft.) Itís available with several gearboxes that provide the correct output shaft speed of around 375 RPM.
Getting the Lister out in one piece is difficult -- we had sold it, so this was essential. While there are soft patches both outboard and above the engine room, they arenít big enough. The whole wheelhouse, funnel, and main deck above the engine room unbolts, but this seemed like overkill. In the end we cut out the piece between the top soft patch and the side one, which provided a hole that was big enough. TheCat went in the same way, but much more easily.[Top]
Some of the vibration undoubtedly comes from the Lister-Blackstone. As noted above, replacing it with a soft mounted engine will reduce vibration significantly. The other major step, much easier, is to modify the propeller aperture to allow the pro wash to flow more smoothly. This year we removed the two eyes outboard of the propeller that are circled in the photo. At her next haulout, we will also remove or fair the stub of the keel (the smaller circle) which also protrudes into the propwash. The removal of the two eyes made a big difference under some sea conditions on our travels after removing them.
Neither the Cat nor the Lister-Blackstone is particularly noisy. A well set up dry exhaust system will generally be quieter than a wet exhaust, and there is plenty of space in the funnel for a good muffler.[Top]
Crossing the Atlantic, we ran at eight knots, burning almost exactly eight US gallons per hour (one US gallon is 3.8 liters -- eight gallons is about thirty liters), including moderate hotel loads on one 9kW genset. We changed the oil on schedule at Horta, but otherwise, she just purred along.
A chart prepared by Milbrookís engineer during several of her trips suggests that the Lister Blackstoneís consumption is about the same. That same chart says that at ten knots, consumption goes up to sixty liters per hour, a 60% increase in consumption per mile. Headwinds will have a similar effect. Speeds slower than eight knots donít reduce consumption much.[Top]
A standard fleet tender has about a 1,200 mile range with a 10% safety margin. The easiest route across -- going to the Azores and then straight from there -- is about 3,200 miles, with a longest leg of around 1,900. There are several other ways to go, within the 1,200 mile limit, however:
Since we expect to cruise long distances regularly, while Fintry was in England we raised the floor of #2 hold one foot from frame 19 to frame 28 (all but the two end frames) for two fuel tanks -- each around 7,200 liters. This, with the engine room tanks, gives the 5,000 mile range required to do a circumnav (we're not planning on going around again, but felt that the boat should have that capability).
While we're on the subject of fuel, note that the original fuel filters are all relatively coarse wire gauze, which are nowhere near what is required for modern engines. Racor makes a high capacity filter (FBO-10) which will handle the output of the fuel transfer pump, so that all of the fuel in the day tank can be filtered in advance.
We then have a pair of Racor 900FH filters in parallel between the day tank and the four diesels and, of course, filters on each engine. If either of the 900FH filters needs replacement, two valves switch the flow to the other one. Since the day tank is above all the engines, priming and air bleeding is very easy.
While smaller sizes will handle the flow requirements, experience has taught me that the large filter elements in a 900 series filter are only a little more expensive than the elements for smaller filters and will last a lot longer if the fuel isn't completely clean. This isn't an issue in the developed world. but is very much one in the third world -- on our circumnav, we once clogged a filter in only ten hours.[Top]
We raised the floor of #1 hold twenty inches to gain two new freshwater tanks -- each around 2,000 liters. We did this because it is now known that bitumen is a carcinogen and Manor Marine told us that removing the original bitumen coating in the existing water tank would be almost impossible. We could use the old freshwater tank for toilet flushing on long trips, particularly if we don't install a watermaker. This would require another pump. An alternative would be to accept the fact that you shouldn't drink the tap water and carry lots of bottles.[Top]
The early Fleet Tenders (from Aberdovey through boats a little later than Fintry) were equipped so that most systems ran on 220VDC. All of the boats also have 24VDC systems for engine starting and emergency lighting. The later boats have 230VAC systems. Since DC isn't very useful on a yacht, many of the DC boats have been converted to AC.
Having converted a DC boat, I think I'd almost rather have a DC boat to start rather than an AC boat -- certainly it's close to a toss-up. Going DC to AC, you have to change out the gensets, or at least the electric ends. That's fairly easy either way as most of the diesels on the boats have been used as both AC and DC sets and the ends are readily available. We put in two Northern Lights 9kW gensets in place of the smaller existing DC set and put an hydraulic pump in place of the the other DC generator (see above). You also have to change the shore power connection and add one or two isolation transformers.
All the lights will run either way (fluorescent ballasts that run on DC will generally run on anything and incandescent lights are omnivorous). We replaced the motors on the fuel transfer pump and the steering pump (using three phase motors driven through variable frequency motor controllers which run on single phase), changed the windlass to hydraulic, and put DC motor controllers running on 240VAC (US$80 each) on the engine room blowers. DC relays won't run on AC, so we had to put a full-wave rectifier (US$10) on coil supply for the relay in the navigation light controls and the water heater (calorifier) control. You could, for a little more money, change the relays themselves.
With all this done, we have a simple AC system, similar to most USA residences, with 240VAC from a generator, an inverter, or shore power, and a center tap providing 120VAC where needed. Everything is single phase, except for three-phase motors whose controllers take single phase input.
The boats that were built as AC boats have complex, three-phase systems, that run 440/230/120VAC 60Hz. You need 440VAC three phase shore power, available only in the very largest marinas, to run any of the motors and you need to pay attention to keeping the three phases balanced on your gensets (this is hard if you're running an electric clothes dryer or water heater). Inverters that supply three phase power are not readily available, so you have to run a genset when not hooked to shore power. And, the AC boats have 11 distribution boxes around the boat.
There's one other significant difference between the AC boats and the DC boats. In the DC boats, the engine room runs from frame 6 to frame 18 . The space from frame 2 to frame 6 is two large tanks P&S and a void in the center. The tanks can be used to adjust the trim of the boat, either F&A or P&S. We normally run with them full; emptying them will raise the stern about 15". While this will make the boat less stable, it might get you off a shoal.
(It's conventional to refer to locations on boats this size and up by their frame number. Frames are spaced 20" apart, frame 0 is at the rudder post and the forward waterline is at frame 45. All the bulkheads below the main deck are located on a frame.)
The AC boats, on the other hand, have a transformer room the full width of the boat from frame 2 to frame 7, and voids below, with solid ballast. The engine room is, therefore, one frame smaller, but the transformer room has a lot of empty space which could be used for various purposes.
So, the choice between an AC boat and A DC boat is not straightforward. Shorepower is a problem for either -- there was 220VDC at Manor Marine, an ex-Navy base, but I've never seen it elsewhere in the civilian world. 440VAC 3 phase 60Hz power is also rare, except at the very largest marinas in the USA. Since only emergency lighting runs on 24VDC, you need shorepower or a running genset (or inverter) to do almost anything.
Since we knew we were going to do a major rewiring, a DC boat was fine with me. I like the versatility of having the tanks aft, but ask me again when we've moved aboard and are looking for storage space.
If you've never dealt with three phase power, read the Wikipedia article Three-Phase Electric Power
By the way, all of our AC electric distribution, which originally occupied an engine room box 60"x30" by 72" high plus various auxiliary boxes around the vessel, and had hundreds of fuses, is now in a single box that is 8"x24"x84" high plus one auxiliary box 16"x20"x8" deep. Itís all DIN rail mounted circuit breakers -- no more fuses.[Top]
As part of the conversion from 220VDC to 240VAC, we took the DC generator end off of the Perkins 6-354 -- the larger genset -- and put on a 60hp hydraulic pump. It drives a 60hp bow thruster, the windlass (which was 5hp 220VDC electric), a future crane, and a 60hp motor mounted above the propeller shaft, with an overgrown bicycle chain sprocket on the motor and the shaft for use if the main engine fails. Estimate is it will do 4 knots.
The bow thruster is a real pleasure. With it, itís easy to move the boat sideways -- parallel parking in a short length. With the rudder hard over, the propeller acts like stern thruster, although, of course, you have turn the propeller forward to go sideways and then for reverse to keep from moving forward. Also, at idle the boat moves about three knots, so if you want to go very slow, you have to be in neutral. The bow thruster provides steering then, when thereís little water going past the rudder.
I've been asked if we could get away with a smaller bow thruster. Given my comments elsewhere in this FAQ about how easy they are to handle without the thruster, I could agree that a smaller thruster would work. The limit is basically how strong a wind the thruster will push against and how much sail area there is. If you don't extend the deckhouse forward, you could get away with less. Our naval architect calculated a 50hp thruster for a wind of 25 knots; we rounded that up to 60hp. As the crosswind gets up into the twenties, the bow will go upwind, but it clearly takes longer, so I'm happy with the decision. In thinking about this, remember that the wind thrust varies with the square of the wind speed, so a 25 knot wind is 56% more thrust than a 20 knot wind.[Top]
The early Fleet Tenders, at least all the DC boats, have 1,000 watt radiant heaters scattered around. None of them have any cooling. Some of the later boats have large three phase electric air heaters mounted near the funnel and distribute heated air throughout, with ducts carefully set up so you can control fire and flooding.
I've never thought much of electric heat, particularly underway, when the main engine will be throwing off ten times the energy that you need to heat the boat in any climate. So we've replaced the electric heat entirely, except for summer domestic hot water while on shore power when we use an electric water heater (calorifier). HVAC is piped heated/chilled water. Heat is a 50,000 btu Way Wolff diesel boiler (Way Wolff supplies most of the smaller vessels of the US Coast Guard). There's a heat exchanger on the CAT for use underway and on the gensets for mooring/anchor use. The system also supplies domestic hot water. Chillers will use the same piping, with the fans on the air handlers reversed.
Speaking of domestic hot water, note that the existing water heater (calorifier) is designed to work with the water pressurized only by the header tank one deck up -- much less than the usual pressure in a domestic water system. We had removed the header tank and installed a 24VDC water pump before we crossed the Atlantic. Although I had recognized the problem and had installed a pressure reducer on the supply to the hot water heater, the tank was troublesome throughout the trip, constantly spring tiny leaks.[Top]
Fintry is very easy to handle, even without her bow thruster. Without the thruster, I just put the bow into the float, put a spring line ashore, put the rudder hard over the other way and idle forward. The stern pulls right in. Since the rudder has virtually no effect below three or four knots unless the shaft is going forward, you have a built-in stern thruster available all the time. She's so heavy that the wind has little effect. One of her sisterís owners has been known to dock his boat (no thruster) single-handed, running down the stairs to put the line ashore. We don't do that, but Dee and I actually prefer it if there are no helpful strangers on the pier, as it's easier for the two of us to do it than to convince strangers to do it our way. We can also turn her in her own length without the thruster if there's not too much wind, something we have to do to get her out of her slip.
With the power steering on, the steering is a little sloppy, so she is quite hard to hold on course. If we're running her for any length of time without the autopilot, we turn off the steering pump. Although it's then 30 turns lock to lock, you don't need much wheel when at speed. As a practical matter, though, we use the autopilot almost all the time, from the moment her bow emerges from between the barge and the pier until we return to that point.
Speaking of autopilots, there is none in the original design. I have seen three different kinds of installations.
Fintryís very comfortable at sea until it gets fierce -- at 35 knots on the nose during our Atlantic crossing, it was bouncy, both pitch and roll, but most boats her size would have been similar or worse.[Top]
The RMAS ran them with a crew of five to seven. When underway, Fintry had a minimum of a watch keeping officer, an engineer whose station at sea was at the engine telegraph in the wheelhouse, a separate helmsman, and a lookout or two.
We operate Fintry in all but the busiest harbors with one person in the wheelhouse.
The only times you need more than one person are:
Dee and I operate Fintry regularly in Boston Harbor, which is certainly as busy as Portsmouth or Plymouth, maybe worse. Either of us alone can bring her alongside her wharf (actually a floating barge) unless the wind is fierce off the barge. The bow thruster helps, but is by no means essential -- point the bow at the place you want to be, go ahead until you touch, then rudder hard over away from the wharf and let the prop push the stern in, killing forward way with reverse as needed. For those who are used to running fiberglass boats, remember that docking a large steel vessel with an 8" rubrail (20 cm fender) is a contact sport. This is not to say that you can be careless while docking. 150 tons of boat can make a big dent if you hit something too hard, but it does mean that you have more ways to control the situation.[Top]
I can't speak to all of them. I've been to sea on Loyal Watcher, Ilchester, and Fintry, and been aboard half a dozen others, including Milbrook, so I've at least been aboard all of the classes except the Aberdoveys. For brief descriptions of each class see The 79' Fleet Tenders of the Royal Navy
We lengthened the wheelhouse (fore and aft) by four feet, which makes a huge difference. The standard wheelhouse is good for maybe three people, Fintry's is good for eight. The wheelhouse (and everything else above the upper deck) is aluminum so this was actually quite easy. And, of course, before we bought her, Serco and the RMAS had extended the saloon forward by about 21 feet (about 6.6 meters). Many of her sisters have been similarly extended.
The Clovellys, Dive Tenders, and Loyals are essentially the same, except for the deck layout, which is easily modified. I'd rather take the empty holds of one of the Clovellys and lay it out to my needs than one of the Loyals and have to work around (or scrap) all the existing stairs and cabins.
The Dive Tenders have a longer deckhouse forward and a full width upper deck aft. I like the full width deck aft -- we added it to Fintry -- but the full width deckhouse makes docking harder, as you must go through or up and over to get from bow to stern.
The four Manlys, I think, are also less desirable, for the same reason -- their deckhouses extend all the way out to the sides as on the Dive Tenders. That would be a nuisance after you're alongside and started putting on normal dock lines. Their only particular virtue is a longer wheelhouse.
The boats with AC electric equipment (after 1972, approximately) have a passage from the engine room aft to the steering flat and the space that is three aft tanks on the DC boats are a transformer room on the AC boats, with a lot of room left over for storage and other equipment. On the other hand, without the tanks, you have less flexibility in trim and draft, particularly if you build in large fuel capacity.
The Aberdoveys, which I've never been aboard, certainly have much less space in the same hull. The wheelhouse is probably a bit more comfortable in a real blow -- itís lower and, therefore, closer to the roll center.[Top]
This section is by no means complete. I'll add to it from time to time.
Since what follows is mostly negatives, let's start with a few positives:
Salt water for toilet flushing and fresh water for all other domestic purposes are supplied from two header tanks on the upper deck. Saltwater is pumped up by using either of the two pumps connected to the bilge, ballast, and fire system. The freshwater has its own automatic pump (on Fintry, this pump is identical to the fuel transfer pump, so when we replaced the water pump, we gained a spare for the fuel transfer). While the header tanks are lagged, presumably to protect them from getting too hot, they are not protected from freezing. And, of course, the sewage flows directly overboard, above the waterline.
First, I should say that as an American owner of a Fleet Tender, I am not governed by the MCA rules and therefore know just enough to be dangerous. This is here because several people have asked about various aspects of getting an MCA certificate.
Fintry had a MCA Class VI and an MCA Class IV certificate simultaneously. They were both very limited -- the former to "Within the limits of the Dockyard Port of Plymouth" and the latter to "Within Plymouth Sound not Seaward of a line drawn from Cawsand to Breakwater to Staddon." I have originals of both certificates as well as her stability book if that would be helpful to anyone. I also have copies of stability books for Milbrook and Fulbeck. I also have basic stability and trim calculations in an Excel spreadsheet.
As built, the Fleet Tenders were Lloyd's 100A1  for navigation from the Elbe to Brest, which is, of course, a far cry from Plymouth Harbor. My Naval Architect (who specializes in vessels of this size for offshore use) is satisfied that the Fleet Tenders are safe for use anywhere in the world, although not the North Atlantic in winter or for an extended voyage in the Southern Ocean.
The RNXS Fleet Tender Handbook (1990) believes that the Fleet Tenders have, without an engine room bulkhead, single compartment stability -- that they will float upright with any single compartment flooded -- so I do not understand why Fintry was subdivided.
One possible explanation is that the engine room in Fintry and, I think, all the DC boats, extends from frame 6 to frame 18, 12 frames, or 240 inches. In at least some of the AC boats, the transformer room occupies the space that is ballast tank on the DC boats (frame 2 to frame 6). The transformer room is one frame larger (frame 2 to frame 7), so that the engine room in at least some of the AC boats extends from frame 7 to frame 18, one frame less. Note that the #2 hold is also 11 frames long (18 to 29), so in a boat with an 11 frame engine room, the largest space would be the #2 hold, not the engine room. It is possible that the RNXS handbook is generalizing from the AC boats....
By the way, as built they are 79 feet exactly when the keel is level. I believe that it would be fairly easy to remove 3.5" to get them under 24 meters (at which length much tougher rules apply). The stern has a small curve in plan view, so that if you burned off the stern plate, then cut the framing forward 3.5", flattening the curve, and welded on a new stern plate, you would have a 23.95 meter boat. The stern framing is very heavy and, although I'm not a naval architect and am not really qualified to suggest it, it looks like you could simply remove the metal and not add any. There's adequate space in the steering flat to do the work, although a small person would find it easier to do the welding.
There are two places you can save significant space in the engine room. One, by replacing the electrical panel which is 6 feet by 2.5 feet by 5 feet high, mostly air. Fintry's new AC panel, all DIN rail circuit breakers, is 24" x 6" x 6 feet high. Since the existing panel has access space behind it, you free up floor area close to 6 feet by eight feet. The other space saver is to convert the Lister Blackstone to wet sump and eliminate the sump tank which is against BH 18 on the starboard side.[Top]
1) Voltage -- Europe is either 220VAC or 230VAC nominal (varies from country to country) while USA is 240VAC nominal. In practice, there's no real difference so you don't have to worry about it So, in everything below, I'll call it 230V and 115V. You must change the voltage appropriately -- the wrong voltage, either way, will fry most equipment. The only exceptions are that a lot of modern electronics has universal inputs which can take either 115 or 230V.
Generally the shore power voltage can be changed at an isolation transformer where the power comes aboard. If you are converting a DC boat (see above), use a multi-tap transformer so you can adjust for often low marina voltage.
2) Frequency. The USA runs on 60Hz; Europe runs on 50Hz. There are all sorts of good technical reasons why you should not run equipment designed for one frequency on the other one. Running 60Hz equipment on 50 Hz risks transformers getting hotter and cooling fans running slower, so overheating and fire is a risk. Running 50Hz equipment on 60Hz risks overloading motors -- things like fans and compressors use much more power at higher speeds.
However, my experience is that almost everything works fine on the "wrong" frequency (in either direction). Specific experience:
There are, by the way, two major technical reasons why 60Hz is better for all purposes.
The first is that 60Hz goes through a transformer more easily, so transformers can weigh and cost less.
The other is that a 60Hz generator will usually run at 1,800 RPM. (Itís possible to run them at 3,600 or 1,200, but the former wears out quickly and Iíve never seen the latter in sizes we use.) A 50Hz generator will run at 1,500RPM. The problem with 50Hz is that it will be the same diesel engine driving the genset at either 1,500 or 1,800 RPM, so the units cost the same, but the slower speed puts out less power, so a 50Hz genset costs more per kilowatt. The fuel consumption curve also favors the higher speed, so the 50Hz gensets also burn more diesel fuel per kilowatt produced.
Iíll guess that this is why the AC Fleet Tenders (and, I am told, all NATO Naval Vessels) are 60Hz.[Top]