Tech Net Q-R

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Query: How to connect a Faruno 1720 radar to a Raymarine C8 plotter?
It's highly unlikely to work. Older Faruno models are analog based.
It will not work with a chart plotter. We have that model. (Salty Paws)

Query: What are the benefits of wideband radar?
It reduces power consumption.
It picks up smaller, closer floating objects.


Query: How disassemble the pump to remove the impeller?
Use a hammer and chisel gently, then use glue to reassemble.
Use a heat source; with a heat sink on the shaft.
Update: Success. Info from manufacturer's site: lock rotor, give it a whack with a hammer and it unscrews easily.

Issue: Raw water flow was low and yet the impeller was intact. Disassembled the hoses and found a very old impeller vane which was impeding the flow.
Use a strainer (inexpensive from West Marine) between the pump and the heat exchanger to capture exploded impeller parts.
If an impeller vane is missing, keep searching for it because it's guaranteed to come back to haunt.

Use a strainer to catch impeller pieces. (Discovery)
Reverse a worn cover plate; install embossed side down. This will extend it's life by 2. (Dyad)
Shaft seal rebuild kits. (Dyad)
Use a dental pick as a tool for seal replacement. (Scaramouche)

(also impellers)


Query: I'm considering adding a computer fan in the fridge unit. has anyone done this before?
One good way improve performance is to make a duct with pvc pipe to direct the cold air from the freezer to the fridge section. Mount the fan in the duct. (Moira)
Make sure the fan bearings can handle the cold temperatures. (Five and Dime)

Issue: Intermittent shut down after engine driven. Affects AC and fridge side only. I have to hold down the temp sensor to get it to start.
The capillary sensor may have residual water that freezes. Remove the water and dry it out.

Query: The controller quit. Is there a get-home fix available?
Not really. It needs a replacement.

Query: What's the best way to plug a freon leak hole?
Use solder after leaving the system at zero pressure. Using acid flux will work.
Use non-silver solder for this application. (Passages)
Dremel the joint a little bit to help hold the solder. (Serengeti)
Wrap it a few times with a heat source to help the solder grab. Keep heat away from direct contact with the wire. (C_Language)

Issue: Have been unable to trace the source of a leak even with the use of dye and black light.
It may be leaking in the evaporator, where it's very hard to detect.

Issue: The thermostat won't shut off unless physically thumped.
Moisture is usually the cause of this problem.
Replacements are easy to install. Use an electronic thermostat as a replacement. (Salty Paws)

Issue: The sender on the temperature monitor freezes up while in the freezer. It works fine on the fridge side.
Use a standard outdoor thermometer instead. Place in a zip bag to prevent moisture intrusion. It's very inexpensive and will last five years or better. (C_Language, Valkyrie)
Update: Success. Placed the temp sensor inside a zip bag and it works. Keeps the ice off too.

Issue: The refrigerator will run with the generator on, but not at all with the inverter.
Check all the connections.
Try the fridge without the high capacity starter, to determine if the starter is the problem.
Disable battery-assist.
Lower the AC voltage cut-out.

Issue: The electronic sensor-stat takes awhile to get up to 12 volts.
Its common for electronics to stall for a few minutes due to vapor lock.

Issue: Refrigeration fuse holder was getting hot. I replaced it and it melted three months later.
Check wiring from the terminal block.

Query: I need to recharge the refrigerant. How much do I need to use?
Look for the number on the plate on the unit for information.
The plate will also recommend which type of gas to use.
Add freon until the return line feels cold, but not to the point where ice forms. (C_Language)
Don't let the line get frosted up beyond the box. If it frosts the line, bleed off some of it. (Discovery)
Use small amounts to refill.

Issue: Thermostat recycles too rapidly.
That's normal behavior when it turns on after being off for awhile.
Clean the contacts and thermostat switch.
Clean the contacts with stiff paper.
Clean with denatured alcohol to remove all traces of water.

Issue: Cracked metal blade on the fridge fan.
Use Aluminum Brazing Rod for repair. Practice on a similar material before putting heat to the blade. (C_Language)
Drill a stop hole at the end of the crack to relieve the stress. (Salty Paws)
Then secure at the edge with J.B. Weld. (Leah Hona)
Aluminum Putty is a good for repair. Use a very thin layer. (Soul Mates)
Try a splice if the crack is due to vibration. Patches may fall off. Then add a bit of weight to other blades for balance. (Dyad)

Issue: Compressor buzzes and shuts down.
Solution: Bled the system and added new refrigerant.
The valve may have been clogged.
It may need a bleed with a vacuum pump.
Thump the unit to dislodge contaminant.

Issue: I need to charge my system, but have no vacuum pump onboard.
Charge it with freon to remove moisture, then drain. Repeat. Charge with freon again. (Naked Lady)
A hair dryer is useful while evacuating. (Salty Paws)

Query: How to fix an evaporator tube that's been broken off?
Use a brazable aluminum welding rod. carries them. They work well.
The surface must be clean.
Aladdin 3in1 is another good product to repair aluminum.
After repair, you'll need a vacuum pump and replacement freon.

Issue: Compressor slows down then stops. Its a problem with both fridge and freezer.
There may be particles in the expansion valve.
Test with ammeter. If current goes up, there may be blockage in the plumbing; possibly ice.
Ammeter: if current goes down, refrigerant may be low.
Remove belt and run with no load to check motor current.
Check brushes on the motor; they may be worn. They're rated for six years.
Expand springs through soldering to lengthen brushes as a temporary fix. Make sure spring or copper connector doesn't come in contact with commutator.
If bare copper is showing, the brush is shot.
Update: Success. New brushes did the trick.

Issue: The unit is running, yet the freezer won't freeze properly.
Check for freon loss.
Remove and prevent excessive ice on plates.
Expansion valve may be iced.
Use a heat shield between plates and valve.
Check the thermostat which may be iced.
Bypass thermostat, electrically, and see if it gets cool.
Check the temperature of the lines by physical touch.
Dye can be used to check for obstructions.

Issue: Thermostat is set to conserve energy yet freezes things like lettuce.
Reposition the sensor to the lowest point in the freezer; place it against the plate.
Use thermal grease on the thermostat.
Change to a Dometic 12 volt mariner unit.

Issue: Adding freon.
Get an adapter from an auto supply store. With the connector, add one can of refrigerant to your system. Its trivial to do.
A newer blend is Freeze-12 which is 'green' and will work in place of R12, which is being phased out.

Danfoss compressors have diagnostic LEDs on them. These can be located on the wiring schematics on the tech sheet: bd35 pdf and pdf. Also available are tech sheets for other models. (Discovery)

Expansion orifice; capillary tube is clogged with Stop Leak. Lesson: don't use Stop Leak in refrigeration system.

Remember to clean the cooling coils periodically. (Valkyrie)

Use room temperature water rather than a heat source. This prevents drastic temperature changes which may cause cracking. (Salty Paws)
An ice scraper is a helpful tool. (Mon Amie)
Use a fan to help melt ice. (C_Language)

Drill holes on the inside of the fridge, then use styrene foam to fill the inner gaps for further insulation. (New Attitude)

I used a two-part self inflating product as further insulation. Mix small batches to work. (Windsome)

The product Great Stuff, a self expanding foam, fills with great force. Make sure you don't overfill. (C_Language)

Great Stuff also comes in a blue formula which expands more gently with less force. (Valkyrie)

MEK (methyl-ethyl-ketone) will dissolve Great Stuff residue. (New Attitude)

Try for fridge parts and a useful forum. (Discovery, Cutter Passages)

Refrigeration on 22 amp hours per day, 12 volt system. Stella Blue and Syzygy document their rebuilds. (Discovery)

A Freon and Halogen Leak Detector a good diagnostic tool for finding leaks. Its electronic and effective. (Salty Paws)

Dwyer makes an excellent refrigeration temperature controller. It runs by temperature or by time. (Discovery)
Newer controllers use less power and are more efficient. It's an add on to improve Danfoss. (Amazing Grace)
Practical Sailor reviewed these October 2013. (Aurora)

A small refrigeration unit that runs on 12 volts. Works very well and can control temperature. It doesn't draw much power. Use 2 1/2 amps at 80% for a hard freeze. Drawback: the unit is heavy and doesn't hold much. Advice: get a large unit. [Several thumbs up]
Use two units, one for freezing and one for refrigeration.
It takes awhile to freeze something from room temp, but it does work.

Kollmann Marine is another good resource for boat refrigeration. This site has a good tech forum and Kollmann has published two books on boat refrigeration. (Discovery, Cat Tales, Anania)
Calder's Refrigeration book. (Anania)

If in the Bahamas: Paul Saunders, an independent refrigeration tech, works out of Cat Island (242-475-0055) and Nassau (242-544-0283). You can also reach him through Donna at the front desk of Fernandez Bay Resort; Paul's mom is the straw lady at the resort. (Soul Mates)

A product called H2Out will absorb moisture. Its good for the fridge. (Trumpeter)

Use Silly Putty to plug drain holes in the fridge to prevent water from running to the bilge (if that's your configuration). It will help keep the fridge cold. (Scaramouche)
Comment: It will also save energy. (Valkyrie)

Use the fresh water tank to cool refrigeration. Create a closed-circuit system. Leave all the saltwater plumbing in place and just cap it off so it may be easily reinstalled later if needed. This fresh water system is working well. (Trumpeter)

Use ultraviolet dye and light combination to detect leaks in refrigeration system. (Dyad)

(also welding,   galley tips)


Issue: The rod rigging creates a resonance or vibration at certain wind speeds.
Take length that vibrates and tie a line to it. It won't stop the vibration, but it will change the pitch/tone to something you might tolerate.
Try wrapping the rod rigging with small line, like monofiliment, to dampen or confuse the air flow.
Slip a tube of something like hard rubber around the rod.
Graphite golf club shaft clamps could work. (Serengeti)

Query: The seal on the hydraulic Navtec boom vang is leaking. Is this easy to fix myself?
The tools are easy to get at auto parts stores and its not a difficult job.
Getting the screw-on end cap off will be the biggest challenge. Its messy. (Dyad)
Use sheet rubber or a leather piece to pad the vice to prevent marring the cylinder. (Lion Heart)
Update: I found a mechanic to repair the boom vang, as I deemed the job too dangerous for DIY due to its pressure.

Query: How to tell when standing rigging needs to be replaced?
Check the connections at the bottom. That's where water collects and would be the weakest point. Look for wear.

Issue: The Harken furler drum is loose on the forestay.
Make sure the key is intact.
Use Loctite on the place where the drum slips.
Make timing marks with a magic marker to see how much it slips.
Check the set screws.
Talk with manufacturer. [ans: tried; they're not responding.]

Query: Where's the best place to purchase line?
Defender for a good price.
Sailnet for a better price.

Bell Testing: Hit the chain plate with a hammer and listen for the sound to test its integrity from time to time. (C_Language)

Our surveyor uses this method. And it does not release tension in the process. (Destiny)

Stop Water chain plate caulk stays flexible and pliable. Found at (Anania)

Automotive windshield bedding compound stays pliable, and is a good choice for bedding chain plate. (Pandora)

Check the sealant every so often to be sure its in good shape. (C_Language)

High modulus lines made of Dyneema have an abrasion resistant core and a 4000 lb breaking strength. (Phoenix)

Top Climber is a perfect mast climbing system. It allows you to reach the top of the mast without a helper. And you can actually stand safely above the mast height. Link has video demo. (Le Bella)
Shop around for better prices.


Query: How can I remove pop rivets?
Drill through it with a small bit, then it should just come out.

For some applications, pop rivets are easier and better than using stainless screws for thin material. (Dyad)

A bolt that continually loosened eventually stripped its threads. An aluminum rivet worked as a perfect replacement. Found at auto parts stores. (Salty Paws)


Issue: A squeaky stuffing box; have applied grease with no change.
Use a drinking straw filled with any waterproof grease and squeeze it under the lip of the sleeve. (Final Lee)

Issue: The rudder bearings are too tight.
That's not uncommon. Address this problem at first sign of trouble, as bearings get harder to work with over time.
Look for new material that doesn't absorb water.

Query: Can I use 5200 to reattach a sail drive faring piece?
Yes. First scrub, clean, then sand to rough up a dry and brittle faring piece. Then glue in place with 5200. (Amazing Grace)

Issue: Possible bent shaft; vibration.
Check the cutlass bearing. That may actually be the source of vibration. (Aurora, Serengeti)
Disconnect the coupling and rotate the shaft. Look for any change in the gap to verify. (Discovery)

Issue: Bronze strut needs straightening by one quarter inch.
Take it to a metal shop. Its too difficult to work onboard.

Query: Which transmission fluid is best for S series Volvo sail drives?
Amsoil. (Cat Tales, Salty Paws)
Volvo recommends changing to motor oil; 15 W40.

Query: Should I change the seals on the sail drives while on the hard. They don't leak, but they're very old.
Go ahead and change them while you've got easy access. They're nearly at the end of their life.

Issue: Sail drive has water intrusion of the oil.
Have a Speedi Sleeve installed.
Use epoxy or similar material to fill in the shaft grooves before installing a Speedi Sleeve.
Use synthetic oil in sail drives. It will hold any water intrusion in suspension without loosing lubrication.

Issue: The shaft is turning while under sail with the engine off.
Problem just started recently.
If you have a cone clutch, it may be worn out.
Leave the engine in reverse position when it's off and you're under sail. This will help stop the prop and will prevent wear.
Check for axial play, which would cause cone clutch to slip.
Check lube. Take a sample and smell it. If it smells burnt, it indicates a burned clutch.
Check for debris. Use a magnet to sweep for microscopic filings.
Make sure your cable is adjusted correctly.

Issue: The shaft is scored due to a worn seal.
Use a stainless sleeve to build it up.
Milk carton-type plastic can be used as a shim for a temporary fix.
Ultimately, a replacement is in order.

Query: How can I tell if my sail drive is electrically grounded?
Use a 12 volt test light. Connect one end to the battery, touch the other end to the sail drive. If the light lights up, then the sail drive is grounded.

Query: I want to inspect my center board. Is there a camera I can use to slip in there and take a look?
Try a sports model Kodak underwater one shot use. (Salty Paws)
Drug stores carry disposable underwater video cams. (Salty Paws)
There's a tool called a bore scope, which is used to run wires. Allows you to see what's there. Lowes/Depot.
Contact a local plumber. They have tools for this type of job. (C_Language)
Update: I used a USB web cam sealed into a waterproof box. Used a flashlight as a light source. Found and fixed the problem which was a jammed line.
The cam sounds like a great idea. It could also be used to check zincs, etc in cold water cruising grounds. (Wind Chaser)

Issue: Cutlass bearing is developing a shimmy.
Replace the bearing.
May actually be an out of balance prop.
Breathing hole may be blocked.
Grease the prop twice a year. (Mon Amie)
It may be a motor mount problem.
Prop may be fouled.

Query; Need to remove seal on shaft coupling. Is it reasonable to use heat?
Use a concentrated heat source to heat the bolt quickly without heating the surrounding area. Then give it a jolt with penetrating oil. (It will smoke.)
Heat, then what it to shock it.
Try an impact wrench.

Query: Is it okay to use lube or Anti-Seize between the prop and shaft to make prop removal easier?
Try a copper based anti-seize.
Tef-Gel works.
Never Seez may be more durable underwater than Tef-Gel.
Use your product on the shaft only.
Valve grind product before inserting the key.
Use care when using prop puller to avoid stripping threads.

Query: Does zinc spray paint prevent barnacles on running gear?
Probably not if the boat gets underway. The paint will likely peel off.

Issue: CV joint failed.
Rotate by hand to feel the fit. If there's no play our sound of looseness, its probably fine.
This could be replaced with a car parts CV joint for around $50 vs $500 for a boat part.
[Counter] Auto part can fail due to needing about 7 degrees of angularity.
Lovejoy may be a better choice. Lovejoy coupling comes in a nice variety of sizes.
Drivesaver may allow sufficient angular motion.

Issue: A dripping prop shaft.
Tighten 1/4 turn.
Make sure it's still movable by hand after tightening.
It shouldn't drip more than 1 drop per minute underway.
It may need new packing.
If boat has been out of the water long term, the packing may be dry.
Teflon impregnated packing is superior to wax. McMasters carries it.

Occasionally practice with your emergency tiller before you ever need it. (Salty Paws)
If backup steering is the auto pilot, practice with that.
Have a compass available where the emergency rudder attaches, to help relay info to the person at the helm. (C_Language)
Use your sails to help.

Volvo recently (and pretty much silently) changed the lubricant for the 130S sail drive from ATF to engine oil. Reading carefully between the lines, it may be due to clutch issues. see Bulletin (Amazing Grace)

If shaft seals fail, install header tank for transmission oil. (Amazing Grace)

Put a tube into the dipstick port. This will maintain the air bubble at the top. (Salty Paws)

Use a lengthwise split hose clamped over the shaft seal. Put it slit down, over the nut of the packing gland. This will prevent the tiny bit of water from spraying. (C_Language)

Remove seal for a sail drive with a 2" diameter tapered wooden plug as a tool. (Salty Paws)

Use Great Stuff as an emergency repair for sail drives. Our boat yard recommended this. (Salty Paws)

We've used a Sharpie pen on a prop zinc with success around the screw. They were falling out prior to this. Paint prior to installation, use Sharpie on contact point/attachment screw. (Early Out)

Use a plastic screw for prop zinc attachment. (Soul Mates)

Trilux 33 works well on the sail drive. It's held up for two years without growth. (Valkyrie)

Speedi Sleeve shaft repair kit for replacing a worn prop shaft seal. It's a sleeve designed for the end-user to install.

Gore GFO Packing has gortex fibers in it and works well. (Cutter Passages)

"Dripless Packing" from West Marine. It has the consistency of modeling clay. Work it into a rope shape and apply. Use in conjunction with regular packing. (Cat Tales)

Port Townsend Foundry for pintles and gudgeons. (Calypso)

Prop shaft alignment recommended measurement is calculated .0001" for each inch of coupling diameter. (Moira)

Shop international. I needed some spare Volvo sail drive covers. The cheapest in the U.S. were over $120 each. I got them for less than half that in the U.K.(Amazing Grace)

(also props,   zincs)


Query: In an emergency, what can be used to replace running lights?
Use a flash light with lens repair tape from an auto store.
Use any kind of colored tape.
For the red, use a ketchup bottle over the lens.
Wrap colored cloth around the lens; use sharpies if necessary.
Use your anchor light to be more visible.

Life Gear LED Glowstick is found in the camping section of WallyWorld. Use as emergency running lights. Grab a few red and green ones to have on hand. Inexpensive. (Barefootin)

Issue: Orca Green Tri-Color light failure; blew the 2 amp fuse.
Trace wiring, look for continuity.
Look for something shorting across the junction box.
Look at the fuse. There may be a short between the fuse and the junction box.
Isolate control board from the wiring and replace the fuse. If fuse blows, the problems is in the control board, if not, the problem is wiring.

LED Nav lights.   Use LED lights only in LED fixtures. If you use LED bulbs in incandescent fixtures, the light will be affected adversely through the colored lens. Example: red may appear pink, green may appear blue. (C_Language)

Tri color LED replacements for Aqua Signal Light bulbs can also be found on Ebay. (Discovery)

Tri color LED running lights use low energy, provide high visibility. Doctor LED carries them. (Geru)

Marine Beam lights are quality built and last for years. (Cat Tales, Salty Paws, Dyad)

(also anchor lights,   deck lights,   LED lighting)


Ospho is an economical rust remover-converter. Makes a good primer coat for rusty parts. (Cat Tales)

Lemon juice removes rust stains (but not mold or mildew). Use full strength and ignore for hours. Stain will be gone. Use on any surface. (Salty Paws)

Prevent rust particles and steel filings from getting all over the boat. Do your work over a carpet scrap, then use a magnet to pull out the metal dust. (Dyad)
Use a plastic bag over the magnet, then invert the bag, which now contains the mess. (Salty Paws)
A good source for magnets are old speakers. (Scotch Mist)

3M Compound/Wax. Use as a rust inhibitor. (Valkyrie)
Collinite brand #845 Heavy Duty Insulator Wax. Protects.(St Jude)
Flitz. Polish, Protect. (Salty Paws)
Gel Gloss. Cleans, removes rust. $5/16oz. (Dragon Seeker)
Soft Scrub. For rust removal. (Solitaire)
Starbrite Metal Polish. Rust prevention. (C_Language)

(also corrosion)



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