Earl Hinz wrote: > > Message text written by INTERNET:trawler-world-list@samurai.com > > on > 1800 rpm?> > > By reading your HP vs rpm curve, you can find the HP generated at a select > rpm and then multiply that by 20 to get the approximate static thrust > developed at that rpm. > I'm sorry, I misinterpreted your earlier message. How do I get a HP vs rpm curve? -- Bob McLeran rmcleran@ix.netcom.com M/V "Sanderling" Docked at Point Patience Marina Hailing port: Wianno MA Solomons, MD Hampton 35 Trawler

This information is useful only if you want a very inexpensive, easy, and extremely accurate method of checking or calibrating a tachometer. The only equipment necessary is commercial shore power, a fluorescent light and some white tape. The fluorescent lamp is actually a gas-discharge lamp with the inside of glass bulb coated with a light-emitting phosphor. The gas is ionized by alternating current and emits pulses of energy. This occurs at the rate of 120 times a second. (60 positive and 60 negative) Because of our persistence of vision we dont see the flickers. We use this very accurate regulated commercial frequency to check our tachometers and also check the output of a genset or generator. A small fluorescent desk lamp may be used as space may be limited. First, gain access to the front of the engine. Place a piece of white tape on the face of the large pulley mounted on the crankshaft(usually the largest pulley). (My pulley is painted white and I could not see the tape but I could see the bolts that hold the pulley on.) Illuminate the front of the engine with the light and (watching where our fingers are) start the engine. Run the engine at 1800 rpm as shown on the tachometer. If the tach is accurate, four stationary or slow moving, white marks will appear on the face of the pulley where the tape was placed. Adjust the throttle until the marks stand still. The engine will be turning at exactly 1800 rpm. If there is a significant difference your tach might be adjusted by a small screw on the back of the tach. Next, if possible, run your throttle to 3600 rpm. At this speed there should be two tape marks visible on the pulley. Using the throttle to make these stationary and, if necessary readjust your tach. Dont use the boats generator to power the lamp because if the generator is off frequency the calibration will be in error. Now connect the lamp to the ships generator and see if the gensets frequency is exactly 60 Hz. The reference mark will be steady, not rotating. If it is rotating slowly dont worry, maintaining precisely 60 Hz is not critical for most uses of shipboard power.

Also, for what it's worth, the diode type isolator which most of us have, will leak current backwards and therefore will discharge your battery to ground, over time, if the battery is left in the circuit. So it's important to shut the battery switches off if using diode isolators. West Marine has been advocating battery "combiners" which do not have the voltage drop when charging and do not leak backwards. They have a big blurb on this in their current catalog. Joe & Debbie Engel Marine Computer Service, Inc. MV "Freda Fly" 40' Tollycraft Tri-Cabin Portland, OR > -----Original Message----- > From: Anne & Henri Monnier [SMTP:seaflat@mindspring.com] > Sent: Friday, May 08, 1998 3:03 PM > To: trawler-world-list@samurai.com > Subject: Adding batteries and inverter > > Bob & Deborah, > Without the diode isolators, all batteries would end up in a huge > parallel > connection, and any load would cause all of them to discharge. The > diode > isolators prevent this from happening. like you, I also have a > multi-bank > charger that is powered from shore or gen, all banks that are > connected to > it are also diode isolated (inside the charger itself). This means > that > there are actually duplicate charging paths on each battery bank. > Yea, that > 1 volt drop.... I have set the charger regulators so that they pump > out an > extra volt to cover for the loss. > >+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+- > >Anne & Henri Monnier > >m/v Sea Flat (50' Ocean Alexander Trawler > >sea_flat@mymail.com > >http://www.seaflat.com > >+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+- > > > >

Hello Everyone We are now planning our world circumnavigation by powerboat. I am reading a new book by Paul Garrison called "Fire and Ice" which is about a couple and child that sail around the globe using there doctoring skill in trade for supplies. They are hijacked around Palau. I won't go further because it is a pretty good read and would be interesting just because of the nautical nature. It is fiction. I just returned from Calgary, Alberta and one of the stories their local paper was following is the hijacking of an oil tanker in China. This is not fiction. Pacific Yachting Magazine reported a retired policeman and wife were boarded, beaten and injured on the east coast. Their equipment was stolen. My request to you all for information is: Are their places in the world that we should just avoid because of repeated safety problems. If you could also add your favorite places not to miss and why we would be most appreciated. Dean Russell Vancouver, B.C. "Atlantis"

I'm looking into the feasibility and cost of transporting a trawler from the State of Washington to Milwaukee, Wisconsin. Can anyone recommend a transport company that serves the West Coast and the Midwest? Any idea of the maximum vertical clearance that can be safely transported? Any other issues that I should look into other than cost, reputation and the insurance carried by the transport company? Dan Stilwell Milwaukee, Wisconsin

Foster Price wrote: > > >Allowing the prop to freewheel will reduce drag, but I'd > > be interested to know if the savings is significant or not > I'm not sure if hydrodynamic drag is the same as aerodynamic, but a freewheeling prop on an aircraft has drag equivalent to a disc the size of the prop arc! A critical step to dealing with engine failure in a multi-engine aircraft is to feather the prop to avoid unacceptable drag.

We have just had a great, quality 1985 '44 trawler surveyed and have been told the aft fuel tanks have leaks. They are painted metal. The tops have rusted because of leaks where the deck fill lines have allowed water to seep straight down down and sit on the tops of the tanks. There are also 2 mid-ship tanks with a total of 490 gallons for diesel (which are fine according to the surveyor). The aft tanks represent a total capacity of 300 gallons. The fill lines on the aft tanks run directly to the top of the tanks; the mid-ship tanks have fill lines that run to the sides of the tanks -- thus any deck leak water doesn't stand on the top of these tanks. Our surveyor says that to replace these two aft tanks we'll have to pull the engines and the mid-ship tanks. It sounds major (and certainly very expensive). The surveyor also mentioned that one solution would be to "patch" or replace just the tops of the aft tanks -- but he also said if he saw that in a boat, it would raise big questions to him... As the boat sits, it essentially only holds 490 gallons on fuel. Is this going to be a problem with re-sale as well as limiting our cruising range. The boat burns 6-7 gph crusing at 9 knots -- 11 gph at 11-12 knots. We certainly have done the math and have questions regarding range/fuel capacity. On the other hand, if you're doing coastal cruising at an easy rate, 800 gallons is a lot of fuel to sit in tanks. We're under the gun as we are going to have to respond to the owner in the next couple of days regarding the survey. Bill & Holley Purcell ex Hawk's Next '86 Albin 40 Does anyone have any advise?

We're new subscribers to the list. We are Russ And Donna Sherwin of Sunnyvale, Ca, owners of a 1981 Marine Trader 44DC. We've owned it about 3 years. I lost the aft rail gate because the hinge wore out and it fell in the water. I would like to find the hinge and latch hardware somewhere. Any ideas? Russ

The following is from an aviation web site, AVWEB, AVflash@avweb.com WILL LORAN LIVE LONG AND PROSPER? Pilots who use Loran-C to get from hither to yon probably won't be forced to free up panel space anytime soon. AOPA says the Coast Guard is planning to continue operating Loran-C through the year 2008, but any extension beyond the December 31, 2000 shutdown target date will have to have DOT Secretary Rodney Slater's approval. "More than 80,000 general aviation aircraft are equipped with Loran receivers," said AOPA President Phil Boyer. "We've fought a long time to protect pilots' investment in Loran equipment and to keep this system operating." The FAA reauthorization bill pending in the House directs the DOT to maintain and upgrade the Loran-C system throughout the transition to satellite- based navigation. Incidentally, the FAA is not installing a DGPS system, but a similar system called Wide Area Augmentation System or WAAS. This system will use a satellite and several ground stations throughout the US. It is more complicated than DGPS but the same idea - known geographical locations providing corrections to the GPS signal. Some of the electronic manufacturers are attempting to sell DGPS systems to airports. Anyway, I wouldn't throw your loran receiver away just yet. Herb Hoffman My Tyme Prairie 29

From: N. Kluznick Krogen 39-006 Palo Alto, Cal. Sea Horse 650-326-9763 N.Kluznick@phc.net Thanks Joe, I needed that. I always thought that the Columbia Bar was to be avoided if possable. Now I guess it isen so bad if crossed during one of its quiet times. Nicholas ---------- > From: Joe Engel > Thanks for the correction. I'm a little over-sensitive to the > repetitive theme about the Columbia River Bar being dangerous and that > no one should attempt it. Same with the other ports on the Oregon..........