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Hi
guys, I have loved reading your articles and have picked up some good
tips. Information I'm after is regardinga 240v fridge-freezer on boats.
I am currently building a 50ft powercat - long, light and low-powered
- in Australia, and want around 250 liters of fridge and 100 liters of
freeze. I have had small 12v fridg- freezer in past boats and while they
were great , the bigger setup seems to be a bit cost prohibitive. This
boat won't be attached to shore power and I didn't really want to have
a genset on board. I have seen high output alternators, great while moving
but don't really want to have to run motors just to charge batteries if
on the hook for a week. I do plan on having 4 X 100 watt panels to help
things allong. Can domestic refrigeration be a viable alternative or should
I stay with the way expensive 12v? Any advice would be appreciated
Based on our recent experience, if you don't want to be tied to a genset or a huge solar array, the best thing to do is use the Frigoboat type of system with evaporator plates and Danfoss compressor, with keel cooling. Cost and power efficient. You do need to build a well insulated box, if you want to keep the power consumption down. House systems are efficient on AC power Ð new models anyway Ð but the boxes themselves are very short on insulation. Regards - Steve
Are
you pleased with the frigoboat keel cooler installation on Wind Horse?
If so, about what depth and width and length aluminum box did you put
on the inside of the hull for a keel cooler and did you use fresh water
or a glycol mixture? (I realize the box only needs 4 sides and flanged
top edges to fasten the fiberglass). Fair winds, David
We use deionized water in the tank. Size is usually a function of what structure is handy. To fit in a couple of the keel coolers with building space is going to take at least a couple of square feet of top. If the tank is eight to ten inches deep, you should be OK. And yes, we're very pleased with the system.
Reading
your website on your new power boat and went through the refrigeration
section. I had long ago figured a powerboat could be made quiet and the
cost of running was less than sail. Your thoughts on hull design are spot
on as far as I can reason and follow my thoughts for a long-legged sea
cruising boat. BUT - on to my question - where can I get power requirements
for the Danfoss Compressors?
I would look up Danfoss on Google. On their website they have extensive data on power vs btu. Steve
Hi
Linda and Steve, We are having currently 6 x 8D as the house battery,
and we are about to upgrade to some more serious batteries. The new batteries
will weight approx. 1600 pounds and will not fit in the old spot. The
current batteries are about midship and about 1 foot in from starboard
(not the best place you would think). We have space right after the engine
room, right on the center of the boat. beam-wise we would move only a
few feets, but length-wise we would shift a lot of weight (800 pounds)
about 15 feet further aft. Now...we are talking about a 35-metric-ton
60-foot boat here, so in my opinion it should not make too much a difference,
but I would be really interested in your opinion. Thank you for your help,
Thomas
Hi Thomas: Moving the batteries aft is a change in trim of 24,000 foot pounds (15' times 1600 lbs). You can easily calculate the change in trim (the stern will go down a bit) if you find out the foot pounds required to change your trim one inch. As a wild guess, if this figure was 7,000 foot lbs, the change in trim would be 24,000/7000 or 3.4" The designer of your hull can calculate this figure for you in a couple of minutes, or you can do it yourself once you have the data. Most cruising boats end up pretty heavy, and tend to trim by the bow, so my guess is that this stern down trim will not be a big problem, and may even things out if you are presently bow down. One way to test this would be to add some sand bags, or a dinghy full of water, to the correct spot on deck and visually look at the water line. - Steve
I
am in purchase inspection of a Lancer 42 sloop, engine Perkins 85 hp.
Another same model would be far away and therefore about $25,000 more
expensive to get with the biggest engine of 220hp. I am aware of hull
speed formula, but these boats were build with planning hull and can speed
up to 12 knots, I guess. Now, how could I change the power engine, do
I need another prop and shaft, to become the most powerful and faster
boat under power? If change, what are such costs and makes it sense, if
the goal is to have just in case a fast boat? Thanks for your opinion,
have a great day, Ute
Hi Ute: There is no easy answer to your question as it depends upon how the boat you have is built. For example, the bigger engine will require different engine beds, a larger exhaust line, bigger prop shaft and prop, heavier support on the prop shaft, different prop shaft bearings. The engine will be much larger, and the layout in the engine room may have to be changed. If all these things were to occur, it would cost you a lot more than the simple cost of buying a new engine, and the boat with the 220HP engine at $25K more would be a bargain. However, it is possible that the boat with the 85HP Perkins was built with engine beds large enough to accommodate the bigger engine, and than the rest of the running gear was built for the 220HP engine and just a smaller diesel was installed. In which case it would be simple to change. If you want a larger engine, I would get a firm quotation from a boat yard for doing an installation - and then you will know for sure. Good Luck - Steve
Please
can you help. We are new to boating and have a 40ft sailboat - recently
the fuel tank was overfilled and as a result a valve in the gage popped
and allowed a considerable amt of fuel into the bilge. I had just cleaned,
polished etc the entire inside of the boat to make it smell OK after being
closed up for some time and now it smells like the inside of a diesel
tank!! Do you have any suggestion what we can do to help eliminate the
smell - we are at Hastings, Victoria Australia and everyone here says
we just have to live with it and it will diminish in time - I want to
try anything - I get sea sick. Your comments will be appreciated. Thanks
Bev
Hi Bev: Tough problem. The first thing I would do is find a company that cleans up after fires and toxic spills and see what they suggest. There are some soaps which work better than others. You will probably have to soak the areas as diesel will get into tiny crevices, much smaller than what you can wipe with a rag. The other thing to try is an ozone generator. These work well with odors. Good Luck - Steve
Steve, I've been sailing over 67 years. I sail a 1973 Pearson 33.
I'm on the verge of installing a Frigoboat Keel Cooler system, which,
as you no doubt know, runs the refrigerant tube thru a shoe outside the
hull for cooling. However, I have concerns about corrosion and marine
fouling, as the shoe cannot be painted.
The salesperson that I'm dealing with said (his spelling): "Sailing
gurus Nigel Calder, Tom Neal, and Steve Dashew all use and endorse the
keel cooler."
Tom Neale is not familiar with it and I haven't yet reached Nigel Calder.
Do you have a track record with the keel cooler? Sincerely,
from the Jersey Shore, George
Hi George: We are using the keel coolers, but inside the boat in a special aluminum fresh water tank (where the bronze cooler is isolated from the surrounding aluminum). While I have not used these before, they should operate the same as the sintered metal bonding plates which we have used on all our fiberglass designs for many years. You will have to periodically clean the coolers from marine growth, but otherwise it should be fine.
As to electrolytic corrosion, the risks with this should be the same as with any other through-hull. From my perspective, it looks like a very good approach for a fiberglass boat. Regards - Steve
Dear Steve, Just finished your Offshore Cruising Encyclopedia. Great ideas and information. My wife and I just bought a Stevens 47 and hope to start applying your theories soon on our planned circumnavigation. Its 500 nm fuel range has me concerned though. Would you advise converting 50 gal. of its water tankage to fuel, leaving 75 gal. of water and a 20 gph genset powered watermaker? - Jim
Hi Jim: No
easy answer to your question. Seventy-five gallons of water would be considered
a lot by most of the boats cruising 25 years ago. But if you were to lose
the watermaker early on a long passage, you would want to be well versed
in living frugally - and have the ability to wash with salt water and/or
catch water off your awnings and decks.
Another
question is the reliability of the water maker and genset.
Then there is the definition of your 500 mile range - at what speed and wind/sea state? Can you extend this by slowing down a bit?
Another factor is the boat's sailing ability, especially in lighter winds. The better the sailing qualities, the less diesel you require.
Finally, have you looked into a fuel (or water) soft type of tank - assuming you can secure it well? Might be that the best trade-off is to switch over a water tank to fuel as you've asked about, and then carry a bladder tank in case extra fresh water is required.
Note: Make sure you keep the fuel and water tanks physically separated. Having a water tank with an internal divider will not work with diesel and water! - Steve
Hello, I am wondering if you have any experience with Whispergen generators. I have read their information and they sound very good, however I have not met anyone who has one to get a first-hand story about their efficiency. Hope you can help. Brent
Hi Brent: I have not had any direct experience with Whispergen. However, the sterling engine concept has fascinated us for many years. The ability to get DC power, domestic heat and hot water from one unit is very enticing. Kelly Archer installed one of these on a boat he recently built and it does work. It remains to be seen how reliable the unit will be - but they seem to have a good reputation in New Zealand. - Steve
Hi. We're about to install rigid (as opposed to flexible) solar panels on our Cal 3-46: looking at a number of options for placement: atop dodger, atop Kato davits at stern, swiveled at side rails--any comments about optimum placement and subsequent sailing/safety issues? Thanks, Glenys
There are lots and lots of trade-offs. But the most important is keeping the panels from being shaded as much of the time as possible. Shading, even a thin line, acts as a short-circuit across the cells and dramatically cuts output.
Assuming your Cal 3-46 is a sloop, I think I would install the panels on one or two vertical poles off the pulpit corner(s) in the stern area. This would allow you to angle them for optimum performance, and they are out of the way of rig shade most of the time. There are a bunch of photos of different solar panel installations in Offshore Cruising Ency. Good Luck - Steve
Hi SetSail!
Following Steve's lead when building our 50' catamaran, PAPILLON, we installed
sea chests to supply salt water to the watermaker, refrigerator, galley
sink and head (stbd side) and genset, head, and deck wash (port). While
at dock in Ft. Myers Beach (Estero River) this winter, the water from
the starboard side has developed an awful stench--this despite:
(a) daily turnover of the water in the sea chest through the refrigeration
system (Glacier Bay),
(b) cleaning of the chest itself about every 3 weeks, and
(c) daily flushing of the head.
The water at the sink and head are the real problems, due to sulfur smell.
Have you experienced this type of problem, and what can you suggest? (The
port side is rarely used and has been left filled with fresh water to
delay the onset of the problem.) Thanks! - Julia P
Flush the lines with some fresh water and bleach. This will kill the algae which cause the smell. You then need to run water through the pipes for half an hour or so. - Steve
What would you used to clean a greasy electric motor body with so that it is clean enough to paint? CRC, acetone, ammonia, 3M adhesive cleaner??? - Phil
The best thing I have found is brake cleaner--comes in a spray can, available at auto parts stores. Be careful about using it as it is flammable and you need fresh air. But it is great for cleaning oil and grease. - Steve
Hi Steve, I need to get a hard drive for my boat, a 52' sloop. My question is what kind of specs do I need to know that the hard drives will keep working if I get into a really pounding sea. I'd like to have 40 Gigs of storage.
This is not the kind of question I'd expect a boat builder to know about, but can you send me on to someone who might have more information about this? Many Thanks, Mac
Hi Mac: We have used both land based and portable computers for years on our boats, and never had a hard drive problem. I suspect if you go with a portable computer, you can't go wrong as these have pretty good shock protection built in.
If you are using an external drive, on a home type CPU, maybe sitting on top of the flexible foam in which is shipped would provide enough shock protection. Steve
Dear Steve, We have a 60' steel PH cutter, mast is 76' off the water. We have had two back to back strikes, one year apart. The first strike took out the Icom VHF, the Simrad instruments and the autopilot. Just after the new electronics was installed (I literally mean 3 days), the boat took a hit at the yard in the water. The second strike took out the VHF again, and so far, the Charles Marine Isolation transformer (it was tied to dock power at the time). No other damage has been noted, and I am convinced that the strikes were well dissipated throughout the mast and hull.
Question: If I install the pom pom at the mast head, does it reduce the efficiency of the VHF antenna also on the masthead? Also, what kind of pom pom do you suggest? The electronics technician told me he could see a burn on a bolt head at the masthead where he thought the lightning bolt jumped from the antenna and ran down the mast. As a side note: both antennas were fried and literally exploded.
Thanks a million for the website, a tremendous resource.
Wow--two hits! Sounds like the damage was minimal, relatively speaking. Regarding the ion dissipating brushes, I have no scientific basis of making a decision. The last time I looked there were several sources, and I chose a pair made by Forespar--one for each mast---as they were quite inexpensive. Some of the manufacturers state they use these on radio and TV towers, with great success. But I have also seen scholarly arguments to the effect that they do not work.
As to any impedance between the brush and a nearby antenna, I doubt that would be an issue, as at the high frequencies used with VHF even a separation of an inch or two would be enough. Regards---Steve
Hi there. We are currently assisting friends to ready their vessel on which we are crewing for the passage from New Zealand to Fiji. We are installing an ICOM 710 SSB, however, as the yacht is of aluminum construction we have run into the interesting question of how to safely earth the radio. We have had a variety of suggestions made to us but would be keen for your advice. Looking forward to hearing from you. Many thanks, Jan
Hi Jan: You have to follow the same procedure with all electronic grounds, not just the SSB. Basically, you want what is called an RF ground. This is different than a simple DC ground. In the ground wire you install "Capacitors". These prevent a DC connection, but allow RF energy to pass through. I've forgotten the required capacitor values, but you can find these in our Offshore Cruising Encyclopedia. Regards--Steve
Steve/Linda: We have been searching in vain through the net to find a new---as opposed to a collectible---taffrail log. Does anyone still produce these devices or have they gone the way of the buggy whip? Any advice on procuring one would be appreciated. TIM & MELISSE
We have not used our log for 20 years. Not sure where you might find one. But I would try a professional navigation supply outfit like Safe Navigation in Long Beach CA, or Bluewater Books and Charts in Fort Lauderdale. Steve
Follow-up
suggestion from a SetSail visitor:
for taffrail logs; look on ebay--they have a variety of used to nearly new logs available--if they do not have what you what, then check back every week. I have purchased three logs--a walker and two Negus, the walker like new, one negus like new and one negus well used but working great. expect to pay about $200-250 - John
Hi SS--Seems to me a transponder is THE way to be seen by other ships. Can these be fitted legally in the South Pacific? Are there competing manufacturers? Andrew
Hi Andrew---you sent this so long ago your probably forgot it, and I just found it. Active transponders have been on my wish list for a long time. I am not sure of the latest status, but Paines Wessex was developing a unit in the UK and the guys at ACR said they were going to do one also. There are SAR units, but in theory these are illegal as they broadcast an emergency target. What we've done in periods of inclement weather, with lots of rain and big seas, where radar would not pick us up and we'd have difficulty seeing the ships, is to broadcast our position, speed, and heading on VHF channel 16 as a "securite" call. Regards--Steve Dashew--SetSail
A backup to my previous question, this boat CSY 37 has a V drive trans. giving it's more complicated arrangement than a strait drive, are these prone to problems?? Thanks again Jim
There is a section in Offshore Cruising Ency on drive trains and V-drives. Bottom line, yes they add a layer of complication, are a little less efficient (more drag in the extra direction change) and typically make working on the stuffing box and shaft coupling a nightmare. But sometimes there is no alternative. Personally, having lived with two V-drives (Borg Warner CR71/72 models) I do everything possible to stay away from them. Design wise, we'd rather make the boat 3' longer so we can fit in a straight drive. However, there are a lot of small boats with V-drives because there just is no other option. Steve
I noticed in your video, BEOWULF: The Epic Continues that she has a fuel flow meter. I have been interested in installing a fuel flow meter on my boat (80 HP Perkins diesel) but have been discouraged because all small capacity fuel flow meters are designed for gas engines and do not have to deal with return line fuel flow. What model / brand of fuel flow meter do you use on BEOWULF and how do you have it plumbed to address the fuel flow in the return line. Thank you very much for your assistance. Downing
Hi Downing: We use a Flow Scan meter on BEOWULF. We normally run between 3 and five gallons per hour and it seems to work fine. Occasionally, when we are going slow--maybe 8 knots at 2 GPH it also seems to work OK. Steve
...with prefilters on your fuel system, how often do you then change the 2ndary screw-on fuel filter... we've been doing it every other oil change (every 200hrs) phil
Hi Phil: We change the secondary filters once a year---but they have never looked dirty as the primary filters do the work.--Steve
I have a catamaran and the water tanks are about 6' long with several baffles to limit surging. There is only one access hatch on each tank at the aft end. There is now quite a lot of white scummy film lightly sticking to the sides and bottom. Although we don't drink the tank water and only use it for washing, is there any way to (chemically) clean the tanks as I can't physically reach most of the tanks surfaces to scrub them--recommendations on chemicals? The boat is based in Turkey.
Hi Arthur: There are lots of scale removers on the market, depending on what sort of minerals have been deposited (I am assuming your tanks are fiberglass--if they are aluminum, the scale could be a form of corrosion). The problem with the scale removers is getting rid of the residue. If this is only a cosmetic issue, my instinct would be to leave well enough alone and not bother with removal (which opens the possibility that the scale is covering small leaks).--Steve
Dear Mr. Dashew, I am a cruising sailor planning on taking delivery of a new Hylas 46 in June 03. I have been investigating traction battery options since reading your Tech Talk Battery Maintenance article on SetSail. In addition to the Trojan alternative source mentioned in your article, Yuassa and IBE also manufacture traction batteries. I am particularity interested in IBE as they are a "local" manufacturer to me and the boat will be commissioned in Long Beach. IBE batteries are about 40% less expensive than the source you recommended and they appear to have good life expectancy (1500 cycles @ 80%)and a 5/15 year warranty.
Since they have been available for many years, I wanted to know if you had had any experience with them and, if so, could share that experience with me. The 40% cost deferential saves me over $1200 on a 1000AH 12V bank so I would like to have additional info to make an informed decision. I look forward to your response. Best Regards, Phil
Hi Phil: Traction batteries for forklifts are a commodity--my guess is that if your vendor has a good track record, and has a good warranty, the batteries are going to be fine. Keep us up to date over time on how they work up. We'd like to know ourselves. Regards--Steve
One of my batteries won't hold a charge too long because either something is draining off some current and/or it got over charged when I was once having alternator problems. Any ideas? How does one test gel batteries? Thanks in advance, Marvin
Hi Marvin: To see if you have a short somewhere just remove the power cables and see if there's a difference. Next, make sure the tops of the batteries are clean (dirty tops will actually cause shorts between the terminals). Finally, batteries usually die from internal shorts between their plates. If the battery gas been overcharged that could cause the plates to warp and short. Regards--Steve
I've got an electrical generating concept to bounce off you. The boat is a catamaran with two Yanmar 27 HP engines. I want to power a Marine Air 16K btu air conditioner without adding a genset (third engine, weight). I'd like to run two 120 amp alternators in parallel on each engine (one regulator per engine) by connecting their fields together. Then add a second 3KW inverter that powers only the airco compressor. A link 20 runs the 800 AH battery bank. What do you think? Thanks, Bill
Hi Bill: There are special regulators made for controlling two alternators at once. These have higher amperage capacity, and two sets of field wires. You will need one of these to make your system work. However, it might be more efficient to go to larger alternators, that will carry the load in total, and then run only one at a time (or just put one big alternator on one engine). Running a single engine, under higher load, is a lot more efficient (and quieter). If you take this approach make sure the pulley on the Yanmar can handle the required HP. These are usually limited by the crankshaft bearings. Steve
Do you have any recommendation on how to isolate a alternator from engine body to prevent electrolyses on metal hull?
Hi Jean Claude: There is no practical way to isolate the alternator case. However, the diodes within the alternator can normally be isolated quite easily by any electrical shop which rebuilds alternators and starters. This will accomplish what you need. Steve
Hi Steve, What kind of sailing instruments (do you recommend) for my 52' sloop? My builder says he's found Raymarine to be more reliable than B&G. And my electronics expert wants me to use B&G. Do you have any preference? And why? Or there is always Occam, but everybody seems to say to use B&G instead. Many thanks, Mac
Hi Mac: My only direct experience over the last 15 years has been B&G. As a builder we installed their gear because it was the most reliable, and caused us and our clients very few problems. But my guess is that today you can probably go with almost any system, and do OK. B&G stuff was/is pricey. But for the high end systems, where you need the performance processor, it still seems to be the choice of most race boats. If you don't need the performance data, then I would buy a more modestly priced set of gear (the only thing you really need is a good depth finder--for wind data you can look at the woolies and water and make a very accurate estimate of what's going on). Regards--Steve
Steve, In your BEOWULF PDF, and in the Cruising Encyclopedia you mention an exhaust pyrometer. For small Diesels---30 to 60 HP, wet exhaust---what kind, brand and range of temperature, sensor and display do you recommend? At what temperature should the alarm sound? Should I fit it closest to the exhaust manifold or closest to the muffler? Thanks for your constant support, Igor
Hi Igor: The location of the pyrometer is something that must be carefully matched to the engine manufacturer's standards---but usually somewhere at the end of the exhaust system, while the exhaust is still dry.
You need to get the specific heat-work corellation data from the engine mfg.
As to pyrometer suppliers, we use a Hewitt. But any industrial supply company, or diesel engine supplier will have something on the shelf. (Also check out Murphy pyrometers.)
Temperature range is usually up to about 650/700C.
Once again, the precise location is critical to getting results that will correlate with factory data. Regards--Steve
Hi Steve, Thinking about upgrading a boat from a 12 volt system to a 12/24 volt system to handle electric windlass, electric winches, water maker, etc while still using 12 volts for electronics and lights. In your opinion, what is the best route to go? Thank you Crawford
Hi Crawford: Starting from scratch, we always go with 24V. You save half the weight of the wire loom, get better service from heavily loaded motors, can have bigger alternators and inverters, etc. The negative is that some electronics require 12V--like car music systems, SSB's, VHF's etc. We deal with these via a 24-12V converter, and an emergeny tap on the 24V bank. The other issue is the engine/genset system. Sometimes it is easier to leave these at 12V with their own battery (which is what we have on BEOWULF). But re-wiring is a different story. The easiest thing to do is leave in the existing wiring look--which means you cut any voltage drop in half. But I don't have a feel if this is an efficient use of the cruising kitty. There's a lot on this subject in the electrical section of Offshore Cruising Encyclopedia. Regards--Steve
I wonder if you have any opinion on electric propulsion? I am considering re-powering with a Solomon system. I have a 30hp Westerbeke diesel at this point. I am cruising full time with lots of hours at anchor. Comparing prices, diesel/electric, is a definite apples/oranges situation, with the result being that I may decide based on my dislike of the internal combustion engine. Certainly would appreciate your reaction to the this concept used in a cruising sailboat. Ross
Hi Ross: I have no direct experience with diesel electric. However, the concept is sound--many commercial and navy ships are powered this way. The key with taking advantage with a sailboat is prop efficiency---i.e., the ability to turn a large prop slowly. But of course this brings in other issues like prop drag (even if it is as folder or feathering), tip clearance, etc. Let us know how it turns out of you go this route. Some before and after data would be great! Steve
Am refitting a Cherubini 44 ketch (engine, tank, wiring cosmetics, etc.). At this point I would very much appreciate any info or source information regarding integral fuel (diesel) tanks. I am considering placement in the keel aft of the sealed ballast section. Is there any long term deleterious effect on the hull glass? Thanks in advance for your attention and effort. Needless to say, I have read the encyclopedia, storm tactics, SetSail info, etc. Great resources. Pete
Hi Pete: Diesel has such low viscosity that it is very tough to keep contained. Tanks that are watertight will leak diesel fuel in some situations. The problem you will have in using the aft end of your keel sump for diesel will be getting a fuel-tight bond of the flange (horizontal and vertical), and then sealing to the horizontal flange with a lid. The diesel and fiberglass laminate should not have a problem. A lot of this depends on the space available in which to work. If you do try this here are a couple of things to keep in mind: 1-The fuel pick up should be several inches above the tank bottom so it misses any crud or water. 2-Have a second pick up to the bottom for cleaning the tank. 3-Any bolts used as fasteners to hold the lid down will require "O" rings under their heads for seal--otherwise the diesel will come up the threads regardless of what you try and do. There are bolts made which have a bed machined under the head for "O" rings. Be sure the "O" rings are diesel tolerant. 4-Test the tank with three PSI air pressure for 24 hours--and make sure it is air tight. Good luck--Steve
Do you have any experience or knowledge about using Ericson Safety Pumps for damage control? I've searched through your books and only found engine-mounted pumps. The Ericson is a prop shaft-mounted pump that runs dry until it contacts water. I would like to know if there are obvious downside factors to using such a system. Thanks, Frank M
Hi Frank: No direct experience with these shaft-mounted pumps, but they appear to me to be one hell of a clever idea. There are several issues to consider. How high does the water level have to rise before the pump starts to work, and how much flooding does that represent? On modern, light displacement and/or flat-bottomed boats it is likely the shaft would be quite high and there could be a problem with the engine's v-belts flinging water around, shorting out electrics, etc. However, on a deeper bilge design, especially one where the prop shaft exits low relative to the rest of the engine, I think these could be ideal. Otherwise, a pump which allows a hose to be run to a low point is probably safer. Steve
PS: keep in what the heeled flood level looks like as well as that when the boat is upright.
What do you think about glazing up the pistons with running the engine so much with no load on it (my father is an engineer with a tractor manufacturer!)? Swan says run your engine occasionally up to 3400rpm and get the soot out!! Sounds pretty scary? What do you think? Regards Phillip
Hi Phil: It is never good to run a diesel for long periods without load. The bigger the engine, the smaller the load, the worse this is. However, this is what most sailboats do--ourselves included prior to our recent genset removal. The key, as the Swan manual alludes to, is to run the engine hard periodically. What "hard" is I am not sure. In our case, with the Hundestedt prop, we always are under load, so I don't think it is that big an issue. We used to run at full rpm for 15 minutes (after the engine was nice and warm of course!) after each charging session. Regards--Steve
STEVE, DO YOU SUCK FRESH WATER THROUGH YOUR SALT WATER ENGINE INTAKE WHEN YOU LEAVE IT FOR A MONTH OR SO, OR IS THAT TIME SPAN NOT REALLY A BIG DEAL? WE MAY HAVE TO LEAVE THE BOAT IN BERMUDA AND FLY BACK TO WORK FOR A FEW WEEKS. PHIL
Rinsing a stored engine with fresh water is probably a good idea. In fact BEOWULF is plumbed to allow us to do this. However, in all of our years of cruising we've never done it, so I'm not sure it is really necessary. One thing to keep in mind is that if the engine's waterpump is used to suck in the water you are OK. But if you force it in under pressure, you have to be extremely careful not to get in any excess which would back flow through engine's valves (since the engine is not operating and there is no exhaust pressure to force it out. Regards--Steve
Have you done any articles or do you have any information available on the cleaning and greasing of winches? Our particular problem is how to remove the top of self-tailing winches so as to get access to the spindle to remove the drum assembly. Any helpful hints would be appreciated. Thank you, JP
Hi JP: The disassembly procedure varies with winch brands and designs. For example, on BEOWULF we have three types of Lewmar winches which each require a slightly different process. The best approach is to find the manuals for your particular winches--or a rigger who is familiar with them. If you use the latter, it might be helpful to videotape the process. Re: the grease itself, both Lewmar and Harken sell a special grease. We often use a light weight lithium-based grease. For the pawls, it is usually best to use something really light such as 3 in one oil (but check your winch mfg.'s specifications). Regards---Steve
How do you "equalize" Gel cell batteries?------RJB
Gel cells are not equalized, and in fact are quite sensitive to over voltage charging! Steve Dashew
Hi, my name is Naroa, I don't know much about boats. I'm doing an investigation on the length of time a 115Hp motor should be going. We have a fleet of boats that coast guard a manmade lake that supplies water to the Panama Canal. We have 3 shifts a day which means that the boats have their motor running for 8 hours. I need to know what you consider the life expectancy of these boats to be? PS Your answer is VERY IMPORTANT.
Hi Naroa: I'd be happy to try and answer your question--but first I need a bit of information.
1-What
sort of engine, gas or diesel?
2-Which make and model?
3-What percentage of time at idle and how much time under load does the
engine spend?
A well maintained diesel---which means change the oil at regular intervals---in commercial service---is typically good for between 10,000 and 15,000 hours of operation. On a sailing yacht, where the engines tend to spend a lot of time unloaded and not have regular maintenance, this figure usually ends up more like 7500 hours.
Taking a guess, if this were a four-cylinder Yanmar, and your Coast Guards spent 1/3rd of their time at fast idle underway, 1/3 at half power and the rest at full continuous power, and if you changed the oil every few hundred hours, I would say you should be able to get 12,000 to 15,000 hours between major overhauls.
Note: Making sure that the engine and prop are correctly matched, i.e. that the engine can reach its maximum rated rpm underway, is a critical factor in your type of application.
I'll try and get you more specific data if you can answer the questions. Regards--Steve Dashew
PS: We came through the canal on our sailboat, BEOWULF, last February (2000/my third trip). Steve Dashew
Hi Steve: Batteries and their maintenance are always an issue on our boat (Grand banks 46 Trawler), so I was very interested in that equalization process you wrote about lately. My simple question is: How do I get this done? I have one of these new IUoU Chargers that does everything automatic--so how can I charge my batteries up to the 15 V you mention when the charger stops charging at 14 something volts and then just delivers a trickle of current to even out the self-discharge of the battery? We have 2 engine batteries 12V/200Ah and one service battery bank of 6 x 2V/650Ah Christian M. from Switzerland
Hi Christian: Many of the new battery charges have an "equalization" level which you can trigger manually. If you don't have this feature, you need to add a charger which has it. Steve Dashew
Steve: In the section on engine exhaust systems in your Cruising Encyclopedia you indicate that the exhaust hose should be suspended on flexible mounts to limit noise transmission. In fact, there is a photo of that arrangement that shows a bracket that is hose-clamped to the exhaust hose. Is this bracket available as a stock part anywhere, or did you have it fabricated for BEOWULF? Thanks and best regards, Scott S
Hi Scott: The exhaust fittings to which you refer are custom made. However, there are lots of ways to do this. You can use eye straps (with soft edges) and tie the exhaust hose through the eyes with light line (we've used 3/16" polyester in the past). This will accomplish the same thing---isolate noise and vibration---and the line is often kinder to the hose than hose clamps. You will be amazed at the difference in noise if you can totally isolate the exhaust line! Good Luck--Steve Dashew
Good afternoon Steve and Linda...Continuing to benefit from owning and referring to your fabulous Offshore Cruising Encyclopedia...A great investment and representative of hard work on your part...I also continue to work on buying that Jeanneau 34 I mentioned to you about a month ago by e-mail, and I saw her for the first time yesterday at her new home in New Bern where she has just arrived from being in the Caribbean for most of her seven years...She is up on the hard for now, which gave me the opportunity to see her hull below the waterline...There is noticeable blistering on both sides...Close to a dozen on each side...They are all the same size...About two inches diameter and all open and faired like somebody has already been working on them....Do you consider this type of hull blistering to be a significant fly in the ointment? I can't find it now, but I recently read an article with the point of view that hull blistering is inevitable and is really not such a big deal...that the core fiberglass remains sound...Do you share this view? Would you say these existing blisters should be filled in? Also the rudder is not on a skeg, which is probably a strike against her would you say? Thanks mucho.
Hi Richard: We've not had hull blistering problems on our yachts as we've used a resistant type of resin system for two decades--so I don't have a lot of experience. But, from what I know, you are correct in assuming if the blisters are on the surface only they are not a problem as long as they are treated and not allowed to progress. Re: the latter, you may want to consider the cost of drying out the hull, and then peeling and/or doing a barrier coat. If not now, at least get a quote for same and deduct from the purchase price. This way you are covered later on if the problem continues to develop.
Re: the spade rudder, if done correctly, these are just as strong or stronger than skeg-mounted rudders and more efficient. You'll find more data on this subject in Offshore Cruising Encyclopedia under Cruising Design and Steering Systems. Good Luck.
Good Day: We are sailing our 48' ketch up the Hudson into Canada this summer. We keep the boat in Elbow Cay in the Bahamas and plan to pull the masts in Albany.
I've seen awnings that don't need to be supported by halyards. I've seen them supported with frames made with PVC pipe. Any idea who sells or might have plans for such an awning?
Do you sell or are you aware of any videos that might be of interest to us for this trip? Kindest regards, Steve
Hi Steve: There are lots of ways of making awnings over the cockpit without support. We typically have brackets mounted on the coamings of our designs for this purpose, and of course there are lots of ways to rig a "Bimini" top. But once you get forward of the cockpit it gets more difficult.
As a quick approach, the one idea that comes to mind is to get some inexpensive aluminum pipe and drop it over (or seize it next to) the lifeline stanchions. You would then probably need fore-and-aft guys, as well as something making an "X" across the boat to keep the awning from racking.
There is a large section on awning design and construction in Offshore Cruising Encyclopedia where you might get some ideas. Regards--Steve
I'm trying to track down the "super juice" eutectic solution mentioned as being used by you to improve holdover plate performance. Where should I be looking? Thank you very much! Don Joyce
Bob Williams at SALT should be able to help. His e-mail address is saltmail@hotmail.com.
UPDATE FROM SetSail VISITOR (added 31DEC01):
Bob WIlliams told me recently that until they resolve some EPA questions with the chemical makeup of the product, they would not be able to market it. Regards, Randy
We are in the process of purchasing an LRC trawler and are wondering about the advisability of including a watermaking system. We don't know which is preferable, reverse osmosis or evaporator. Any thoughts on types, preferred brands, tradeoffs, etc? Any help would be hugely appreciated. Thanks, Tom C. and Bob S.
Hi Bob and Tom: This is a big subject with a lot of angles. First, wait until you are ready to go cruising for the watermaker--if you get one at all. They are not happy sitting around and prefer to be worked.
This subject is covered on our Offshore Cruising Encyclopedia--but in general, it has been years since many folks used evaporators for distillation. The modern systems--if you get the simple ones--are highly productive, relatively cost efficient, with many options for power (as opposed to just using waste heat as with an evaporator).
Several keys: Get more rather than less capacity as the unit will run less and the cost differential as you go up on size is usually not proportional. Make sure the membranes are installed where it is relatively cool. Keep all plumbing fittings, valves, gauges, and pumps where they are easily accessible. The watermaker will be the highest maintenance gear on board. Use a built-in system for fresh water flush and cleaning/pickling. Good Luck, Steve
Dear Steve and Linda: Your Offshore Cruising Encyclopedia was extremely helpful to me when I was outfitting my BCC "Calliste" for extended cruising in 1998. Currently in Tin Can Bay, Qld., Australia, on hard stand, repairing a gelcoat failure and discovering other maintainance problems as well.
I have removed her two ss water tanks and was using a welder's Ss pickling paste to remove the rust that developed around the welds on the outside of the tank. This revealed some deep pitting in some places, what looks to be a depth about half the thickness of the metal. Having trouble on deciding what to do, got any ideas to pass along ???
Have been enjoying your web site and will continue to do so, when we depart OZ. Sincerely, Douglas
Hi: You have posed a tough question to answer from 8000 miles away! My first impression would be to ask a local stainless fabricator what he thought. Second would be to pressure test the tanks--but gently! Using a manometer (not water pressure from mains) I'd try an increasing head pressure to perhaps six feet--and watch for leaks.
If the tanks are not too difficult to get out, and they pass the pressure test, I'd be tempted to put them back.
Note: the main thing with stainless steel corrosion is keeping it in the air. As long as it has fresh air, it will usually take care of most surface corrosion. The problems start when it is sealed--as with a bolt embedded in a laminate. If the air cannot get to it, the crevice corrosion can spread quite rapidly.
(You should be able to find more data on this in your copy of Offshore Cruising Encyclopedia).
What I would not do is to try to cover these areas with corrosion with some sort of epoxy--this would exacerbate the problem with time. Good Luck--Steve
Where can I find more information about "pillow block bearings" that you mention in your book Offshore Cruising Encyclopedia under the section on Mega Alternators (page 870).
We have a Northern Lights 8kw genset aboard and I would like to mount a high output alternator on the unit. Presently we seldom place much of a AC load on the unit and by placing a big alternator on it we could "kill two birds with one stone"; charging our battery banks as well as providing AC needs and placing a reasonable load on the engine.
The folks at Northern Lights were not overly excited about this idea (side load on the front seal and bearings). Space constraints do not allow for an opposing "slave pulley" to offset the side load of the proposed alternator.
I noticed in your book a reference to a "pillow block bearing" which alleviates the side load problem. Any other ideas would be greatly appreciated. Fantastic reference book. Thank You, John and Deanna
Hi John and Deanna: Pillow block bearings are available from any industrial bearing supply house. The tricky part is how you support these.
In most cases the support picks up the front and rear mounts of the genset or engine, and projects forward. Sometimes there is enough of a bolt pattern to just put a set of mounts sandwiched between the forward mounts of the diesel--but usually it is best to pick up the forward and aft mounts.
What you do not want to do is to mount the bearing directly onto the boat as it will then not vibrate in sympathy with the engine--which will cause all sorts of problems.
The next step is a "stub shaft" which attaches to the front power take off on the crank shaft. This stub shaft includes the various drive pulleys, and a projection forward which is supported by the pillow block bearing.
The alignment must be engineered correctly--otherwise the front bearing and seal will give problems on the diesel.
There are two other approaches. One is to have dual, opposed alternators. Since you do not have space consider adding one or two really large AC battery chargers, rather than the alternators. It may end up that this is a simpler, less costly approach than trying to re-engineer the front end of the genset (although we use pillow block bearings on a common basis on our systems, we are working with ship engineers who are familiar with this approach, so it is cost effective). Good Luck--Steve Dashew
Hi, I just received my video of BEOWULF in the S Pacific...my wife and I watched it twice, back to back, and were totally impressed with the video and of course BEOWULF.
My specific questions are equipment related:
I would appreciate any advice you can give as we are in the middle of a retrofit/upgrade. My wife thinks that your video is going to cost us a lot of cash, but she won't let me make an offer to purchase BEOWULF!!! Regards, John
Hi John: Converting a boat not specifically designed for water ballast usually adds a layer of complication without commensurate return in comfort or speed. Having said that, if you are going to be using your fresh water or fuel supply, you will be able to use pumps of much lower capacity than what we need on BEOWULF--and for fuel they need to be designed for the rigors of pumping diesel.
The sea-water pump we use on BEOWULF is made by Scott Pumps, and is a 3/4hp model, designed for self-priming (305 524 6776 is their phone).
As to controls, this can be done manually, or with electrically operated valves. We use one of the latter for dumping sea-water (with a manual override). I do not recall the mfg. however, these are readily available from most industrial plumbing suppliers.
The fuel hour meter is made by Flow Scan. These are sold by most large marine distributors. They are not difficult to install, and in our case, with a controllable pitch prop, are a real help. However, with a fixed pitch prop I'm not sure I would bother.
There is data on flopper-stoppers in both Offshore Cruising Encyclopedia and our new Practical Seamanship. The ones we like best are sold by West Marine and they are very effective when deployed at the end of a spinnaker pole.
Good luck with your retrofit! Steve
Hi Steve: I have read, with a great deal of interest, several of your publications. Being interested in yacht design, I have learnt much from them. I am interested in the water ballast system you have installed in BEOWULF. It puzzles me that these water ballast systems use only sea water. Why not use the fuel and potable water that is already on board and move that around? BEOWULF would have some 12,000 lbs of combined fuel and water if all tankage was full. Why increase displacement by bringing on board an extra (up to) 7,000 lbs of salt water? The extra displacement will increase absolute stability, but is this necessary particularly when it is at the cost of added hull resistance? There could be separate ballast tanks to carry sea water when potable water and fuel are low. I would imagine there would be a case for the use of already on board fuel and water. Would you agree? Is there a reason you don't do this? Also, would it make sense to install ballast tanks well aft, say in the stern, so as to adjust the fore and aft trim in heavy downwind/surfing conditions to keep the bow/cutwater out off the water to mitigate broaching tendencies? Many Thanks, Henry
Hi Henry: How liquid ballasting systems are treated is very much a function of construction material, and the needs of the boat. In the case of BEOWULF, being of aluminum she has a double bottom which already has fresh water and fuel tankage for about 1,200 US gallons of liquid. This is way more of both than she normally needs or carries.
The salt water ballast, carried in the hull side tanks, can be dumped when motoring or in lighter winds. If this were fresh water, or fuel, you would be forced to carry the weight.
However, we have done many fiberglass boats where both fuel and water were carried outboard, along the hull side. In this case, we usually design in about twice the required capacity, so it can all be carried to weather. This is a case of the material dictating the tankage as with fiberglass it is not practical to have thin, hull bottom tanks.
On the issue of trimming fore and aft with the liquid ballast: This can certainly help. In BEOWULF, for example, we fill the aft tank first, which pushes the stern down, increasing aft prismatic and helping steering control by keeping the rudder from ventilating (breaking the surface at the hull intersection). Hope this helps--Steve Dashew
I live in Alaska and have been doing a fair amount of work on refitting our 20 year old fiberglass cutter. Electrical, mechanical etc. I purchased new set of tools dedicated to the boat so it means keeping the tools on the boat.
My problem some of my