Harry Sweica on engine maintenance and repair
Harry Swieca has run a boatyard, and he is a registered marine surveyor. He's certified in the repair of all marine engines.
ONE TACH TOO MANY:
I have a 2QM20 Yanmar engine that's great. But after the ignition switch and starter motor started acting up, I installed a new switch, and replaced the starter motor. But while I was taking the starter motor off I accidentally touched the adjacent s- terminal on the starter motor with a tool and the resulting spark started the engine. I turned off the engine and completed the installation. But now the ignition key switch won't illuminate the engine panel lights or power the tachometer. I know the alternator is charging and I've run a new wire from the ignition switch to the positive starter solenoid. Have I damaged anything? —Bill Robinson, Monterey Park, CA
Harry Swieca replies: The worst damage will be a few burned out light bulbs, and possibly a damaged tachometer. Although the solenoid will start the engine, your wiring arrangement appears to have bypassed the rest of the boat. To check this out, get power directly to the panel with a power source that runs from battery positive and engine ground. If the panel lights still don't work, look for an open circuit—either a burned fuse or a melted or broken wire—between the ignition switch and the panel.
Replace what is broken, making sure the replacement fuse is properly sized. If the panel lights now work but there is no reading on the tach, look for a damaged source wire running between the tach and the engine alternator. If the wire is good, you are going to have to replace the tach.
FOUR STROKE STORY
I am considering installing an outboard motor on the transom of my 19-foot sailboat but I'm not sure whether it should be a new 4-stroke design or the standard 2-stroke motor. Is there much of a difference? —Ben Graham, Little Compton, RI
Harry Swieca replies: Horsepower is horsepower, and whether it comes from a 2- stroke or 4-stroke motor the physical output is the same. Choosing between the two is determined by how much maintenance you're willing to do, how much vibration you're willing to put up with and whether exhaust smoke on startup bothers you.
The advantages of a 2-stroke are quick acceleration, light weight, and a solid track record. The disadvantages are that the fuel must be properly mixed with 2-cycle oil, there will be a lot of smoke on start-up, and in some cases considerable vibration.
The 4-stroke motor is smooth running, quick starting, quieter and has little or no exhaust smoke. However it does need to receive regular oil changes and yearly tune-ups to keep it at peak performance. Four strokes are also heavier than the 2-stroke motor, and the price can be 1/3 more than a 2-stroke.
Get the names of sailors who have the product and get their opinion on the motor's performance, and problems, if any. Things to look for in all outboard motors are good cold weather starts, performance in rough seas, minimum vibration transferred to the hull, and modest maintenance requirements. When you have this information you can make an informed decision about what motor type you want. Then consult your dealer for a recommendation on size.
You didn't say whether your boat was originally equipped to mount an outboard on the transom. Adding an outboard to an improperly supported transom could result in hull damage and loss of the motor. If possible, contact the boat manufacturer and find out what should be done prior to mounting the outboard bracket. If they are no longer in business contact a fiberglass expert for his opinion. The transom may well require additional supports and a backing plate. If the outboard you choose provides battery-charging output, check that your boat's electrical system conforms to the American Boat & Yacht Council recommended standards and practices. More Q&A below . . .
Nigel Calder on Boat Systems and Maintenance
Nigel Calder has built several boats of his own and has published many books on boat systems and maintenance. His most recent is Nigel Calder's Cruising Handbook; International Marine/McGraw-Hill
All pumped up
I take my Contest 35 offshore and would like to attach a macerator pump to my holding tank so I can off load when I get outside the 3-mile limit. But I don't want to lose the ability to also flush directly overboard. The best configuration I can come up with is to add a second Y-valve that would channel the off flow either from the toilet (via the first Y-value) or from the macerator pump to the thru-hull fitting. Am I making this overly complicated or am I just asking for too much?—David Boguki, Portland, OR
Nigel Calder replies: Unfortunately this might not be as simple as just adding another Y-valve. If the discharge line from your toilet (via the Y-valve) into the holding tank enters the holding tank at the top (which most do) there’s no spot where you can attach a macerator pump that will empty the tank; you need a hose fitting that comes out of the tank bottom.
However, your deck fitting for dockside pump-outs should be attached to a fitting on the top of the holding tank; there's an internal pipe that goes, more-or-less, to the bottom of the tank. If you put a T into this line between the tank and deck fitting you should be able to suck the tank down with a macerator pump from this point in the system as long as the deck fitting is airtight. I'd also suggest that you put a valve in this line and make sure it is closed when you are using the dockside pump-out facility. The closed valve will keep the pump-out device from sucking through the macerator pump, rather than the tank. To further reduce the change of failure you might also think about installing a manual diaphragm pump rather than an electric macerator pump.
Finally if the bottom of your holding tank is located above the static waterline you might think about flushing the tank well, and then adding another 1 1/2" hose fitting to the base of the tank and plumbing it, through a valve, to a T fitting at the discharge seacock. When the seacock and the valve are open, gravity will drain the tank without the need for any pump.
Our sailboat came with two large batteries and a Heart Interface charger/inverter. We decided to wire the positives from both batteries to a 1/2/both/off switch and wired the battery switch to a terminal bar that holds all the other positives for the inverter, the engine, the refrigeration, 12V circuit panel etc. We wired the battery negatives to a negative terminal bar that contains all the other negatives; engine, inverter, refrigeration, 12V circuit panel etc. The problem is that new we can’t hold enough charge in the batteries to start the engine. The former owner had wired the inverter positive directly to battery 1 but both batteries were wired to the 1/2/on/off switch.
Our thinking was that we could draw from one or both batteries when we used the inverter and the terminal bars seemed to make a cleaner installation. Have we done something wrong and can we test the batteries?—Kelly Reed, Gaithersburg, MD
Nigel Calder replies: There is nothing wrong with running all positive leads to a single busbar or terminal bar as long as every lead also has an appropriate fuse or circuit breaker. This arrangement will not cause your batteries to go flat, which makes me wonder whether they are being properly charged. I've got one scenario that might prevent them from getting the charge they need. If your inverter has a battery-charging mode for use at the dock and the inverter is hard-wired to one bank with a paralleling circuit between the batteries, both batteries will be charged no matter what the switch position is. But with the inverter now wired to the busbar, nothing would be charged if the switch were turned off.
Before you test the batteries make a simple test of the cranking circuit. Place one probe of a DC voltmeter on the positive battery post and put the other on the positive terminal to the starter motor. Then watch while someone cranks the engine. The voltage drop shouldn't exceed 2 volts and hopefully less. Do the same thing using the starter motor case and the negative battery terminal. The drop should be no more than a volt. If you get higher numbers with either reading you have excessive resistance in the starting circuit. You probably have undersized cables, poor connections or perhaps both.
If the starting circuit is OK, here's how to do a quick battery test. Disable the engine so that it will not start (on a diesel either pull out the 'stop' lever or shut down the fuel rack on the injection pump). Then, with the DC voltmeter planted on both battery terminals, crank the engine for no more than 10 seconds. The battery voltage should initially drop, maybe by as much as 2 volts, but then should stabilize and decline very slowly. If it starts to drop again before the 10 seconds is up, the battery is either discharged or is in sorry shape. Recharge it and try the same test. If the voltage still won't hold up the battery must be replaced. Never crank for more than 10 seconds because you could burn up the starter motor.
Not long ago you wrote in SAIL Magazine that you had cut and spliced the cable that ran from your GPS antenna to the GPS unit. Because it is a co-ax cable it cannot be cut and spliced without causing an impedance bump, increased standing wave ratio, and increased signal loss. It might be possible for a manufacturer to cut and splice co-ax when they make it because they would have a spectrum analyzer and tracking generator to test the result.
However, slicing co-ax is something you should do only when the cable is cut and there is no other choice. Cutting off the connecter, unsoldering the short piece of cable from the connector, and then reinstalling the connector on the cable after running the cable through a deck fitting is possible but it really depends on the connector.
One should never cut a co-ax cable unless a repair is required. If the antenna end of the cable is permanently installed there is no good way to check out the cable. If there is a connector at each end you could check the redone cable with DC using an ohmmeter. You then could use an RF power meter, a transmitter, and a dummy load to test it out at a frequency that is near the cable's operating frequency of the cable, which, for GPS, is microwave. A spliced cable can have a lot of signal loss and that increases the risk of having a dead area between satellites. That, in turn, creates a decreased sensitivity within one's entire GPS system. —Malcolm Mallette, (WA9BVS), Indianapolis, IN
Nigel Calder replies: Clearly Malcolm knows a lot more about this than I do but I did splice my co-ax cable and I did not have a problem. Maybe I was lucky and maybe there was some signal loss. But it wasn't enough to cause me any problems.
However, I do agree with him that cutting a co-ax cable is generally not a good idea. And since cable glands on the market are large enough to take a 'full-sized' co-ax end fitting, cutting and splicing a cable should never be done except in a genuine emergency.
I own a 1994 Hunter 23.5 that has a Honda 9.9 hp outboard with a 12 amp generator, I have installed a second battery with a battery switch and I want to be able to monitor the battery levels and the power output from the motor when it is running. What would be a good way to set this system up? —Jack Richard, Moncton New Brunswick, Canada
Nigel Calder replies: although there are a number of system monitors out there that will do the job, Heart Interface/Xantrex's 'E-meter' is a well-proven unit.
Gordon West on electronic communications
I have a 1991 Beneteau Oceanis 370 and I want to put a TV/DVD unit on my boat to keep my 10-year-old entertained. Do I run this system on 12 volts DC, or will I need to get an AC external inverter? Which set up draws the least amount of power?
—Steve Ura, Raleigh, North Carolina
Gordon West replies: You want equipment that will work directly off of 12 volts without an inverter. This will save you some amps plus reduce inverter noise sneaking into the TV over-air reception. The largest 12-volt TV I know is made by Audiovox. It sells for less than $250 in the Consumer's Marine Electronics catalog.
Because most 12-volt TVs are 9-inch, your son and his friends should appreciate the slightly larger size. You also need a 12-volt DVD player; Audiovox makes that unit. Because the automotive markets also are involved in keeping kids entertained on long distance drives, 12-volt TVs and DVDs are plentiful and work just fine out on the water. None of them are weatherproof so be sure to keep the equipment dry.
ON LINE AT SEA
I have a 44-foot sloop in the Med that I plan to keep there for several years. With my ICOM SSB and my Dell laptop, what options do I have for getting e-mail service at sea to the U.S.?
Gordon West replies: Except for their original M-700 unit, all ICOM marine single-sideband transceivers can do e-mail. You will need a modem from SCS to interface your PC to your marine SSB. One good modem is the PTC-II Pro from Farallon Electronics and their dealers throughout the world.
Several commercial e-mail radio services do not require ham radio licensing and one of the largest is SAILMAIL, with information at sailmailprimer. The commercial e-mail service costs about $200 a year, and the modem, which can also serve as a weather facsimile decoder plus powerful DSC reception enhancer, runs about $1,200. Get a competent marine SSB installer to plug everything in and program it all correctly. Once you are on the air, e-mail is at your fingertips with no monthly fees other than the modest annual charge.
I was working on the electronics panel in my nav station, and I discovered that my depthsounder wires had pulled loose from the silver plug on the back of the unit. When I reconnected the plug, everything seemed to work fine, but the plug won't hold. What should I do?--Jerry Watran, Anaheim, California
PASS THE KEY, MR. FRANKLIN
How well do those $99 lightning-alarm systems work? I plan to sail in the Gulf of Mexico, and I want as much warning of a potential lightning strike as possible.--Jim Reybold, Tampa, Florida
Gordon West replies This is a common problem where constant vibration works the silver connector jack loose. One or both of the little micro-screws vibrates loose, and the weight of the wire gradually tugs on the internal connection until the wire either breaks or momentarily shorts. Look around for both of those tiny screws that hold the silver collar together. Gently push the entire wire set back into the plug, and then tighten each screw. You might want to tighten up all of the other micro-screws on your electronics. Connector jacks constantly loosen, and you should periodically tighten them with a jeweler's screwdriver to ensure a good connection.
Gordon West replies Lightning-alarm systems do work. I observed the SkyScan lightning-storm detector in action during an el niño season on the Pacific Coast, and it sounded off when we spotted a distant lightning bolt traveling from cloud to cloud. A lightning discharge creates radiowave-like static that can be easily detected with an alarm system or even a simple AM or marine SSB radio; it sounds like a sharp crack over your radio receiver. The intensity of this audible snap might help you determine how close you are to the lightning.
If you have radar, turn it on and turn off all interference filters. Look for a clearly defined cluster of echoes that resembles a cotton ball on the screen. The cluster is probably a big storm cell that's returning the radar echoes. You can use your radar's electronic bearing line (EBL) to keep track of the storm's relative position while you're sailing the other way.
If lightning is flashing all around you, turn off all your electronics--kill the master switch--and instruct everyone down below to stay away from metal objects. About one second before your boat receives a direct hit, your hair will literally stand on end. After the hit, check that everyone onboard is okay and then check your bilge to make sure that the hit didn't blow out a through-hull.
Don Casey on sailboat care and maintenance
Don Casey is the author of "This Old Boat" and many other books and articles on boat repair and maintenance.
My Bristol 24 has an open well aft, so that the shaft for the outboard engine can go down into the water. But the bulkhead that separates this area from the bilge is wet. I want to fiberglass over the well and move the outboard to the transom.
I'd like to dry the bulkhead before I apply the fiberglass but I'm not quite sure how to proceed. Can the bulkhead be dried and treated with an absorbent resin, or should I replace the wet wood?—Carlos Linares, Staten Island, NY
Don Casey replies. I am going to assume that you are talking about plywood bulkheads surrounding your well. If saturated is an accurate description of the wood, replacing them will be less work than drying them out. Saturated plywood is also likely to be suffering from delamination, which destroys the wood's integrity.
There is no practical way to quickly dry plywood in situ, but if you can keep water off it, eventually it should dry out. You can speed up this process with forced air from a fan or a small heater but be careful not to overheat anything. If you apply epoxy resin to a wet bulkhead the resin will cure, but it won’t displace the moisture that is trapped in the wood. So the wood does need to be dry before you seal it.
If the plywood is just wet and not fully saturated, you could cover the hull opening now and come back to the bulkhead in a couple of months. By then it should have dried out on its own. However, if the wood still is saturated you should replace the bulkhead.
GETTING A FRESH START
I want to remove the old varnish from my boat's teak and holly sole. Can you tell me how to proceed?—Ken Germain, Hockessin, DE
Don Casey replies: Are you sure you need to remove all the old varnish? If the varnish is not peeling and if water has not penetrated the coating and discolored the wood underneath, a thorough sanding with 100-grit sandpaper will prepare the surface for a fresh top coat or two. But if the existing varnish must come off this is one of the few places on a boat where I would recommend a chemical stripper. Though a heat gun does make short work of stripping varnish on solid wood, scorching thin veneers like these would be disastrous. Mask all surrounding surfaces to protect them from the stripper and after the stripper has done its job, lightly scrape the surface with a scraper—never use a putty knife. Now use a palm sander to go down to bare wood. This should require minimal wood removal. Also be careful with the chemical scrapings because they contain potentially-damaging chemicals. Once the surface has been sanded, apply an appropriate number of varnish coats.