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 Wednesday, June 18, 2008

Packing Box Maintenance

There are several different types of packing boxes, including the dripless because they are lubricated by water from the cooling system. Most other boxes are very similar. They form a sleeve or a chamber around the shaft that contain, as we call “packing”.  Which water can’t flow through when it’s compressed; however, the packing allows the shaft to spin.  The packing is compressed around the shaft by tightening the packing nut to the point at which it drips only occasionally and remains barely warm when in progress. This is the importance to checking the packing box whenever taking the boat out.  Because when the packing is gone or disappears, allowing more than 12 drips per minute to penetrate the bilge while in progress, or allowing any water at all to enter when standing still, then you need to follow the next step.  Try tightening the packing nut and it should solve the problem, but if it does not reduce the flow, then it causes the packing box to become more than warm to the touch. And that means it’s time to renew the packing. 

 

How to Renew Packing Box:

1.  First have to back off the locking nut. Water will flow into the boat when the packing nut is loosened, so be prepared or do this job when the boat is hauled. Position yourself so you can reach the packing box with two wrenches.  Crescent slip-joint pliers with jaws to fit will be nice to have too. (Sometimes you may have to resort to a hammer and punch.)  Each wrench handles should be moved toward each other to loosen, away from one another to be tightened. When the lock nut is loose, remove the packing nut.

2.  Get rid of the old packing material with a pick of some kind. The best picks look like a corkscrew and have a flexible shaft, but you can make your own pick.  Packing boxes have the packing inside the hollow core of the threaded sleeve. But be careful, sometimes you will find it in the packing nut instead of the sleeve. It doesn’t matter what kind, just make sure you take out all the old packing. Also make sure that there is no sand or grit left behind because that could score the shaft.

3. Cut pieces of packing material to the proper length to go around the shaft in a full circle. Typically, you can determine this length by using a fabric tape measure or a string.  Be sure not to wrap the packing material too tight around the shaft because your rings won’t seal.

4.  Wrap the rings of packing material around the shaft between the sleeve and the nut. The points at which they come together should be staggered, with layers.  The three layers should be at four, eight and twelve o’clock, and with four layers at three, six, nine and twelve o’clock. Now push the packing nut over the rings so they enter the nut.  The packing material must then be pressed into the nut tightly with a small screwdriver. (Screwdriver blade needs to be blunted so it will not dig into the packing)

5. When the packing is tightly seated, tighten the packing nut and then loosen it to see if the packing still looks consistent. Tighten it again with a wrench, but don’t apply too much pressure. Run the boat in gear and monitor the drip. Now tighten the nut until the drip decreases to fewer than 10 a minute. The following day, run the boat again and check the drip.  If it’s in the three to six range, tighten the lock nut hard against the packing nut, using the wrenches as described in step 1.

 

Don’t forget that you need to check the warmth of the packing box whenever you take your boat out. Also you need to check the “packing” and make sure that it’s still there and has not dissolved.

Good luck!!!

This picture shows the shaft, packing box, packing nut, the homemade pick and the packing.

Picture Credit: http://images.google.com/imgres?imgurl=http://i.pbase.com/g6/84/622984/3/77227844.dv2cAn4V.jpg&imgrefurl=http://www.pbase.com/mainecruising/stuffing_box&h=293&w=400&sz=22&hl=en&start=41&sig2=0k-WfhHRWXaIsh-PbDWtIA&um=1&tbnid=0mf0ImrCObN0NM:&tbnh=91&tbnw=124&ei=3HJZSK2fLaSSggLfpK2zCQ&prev=/images%3Fq%3Dpacking%2Bboxes%2Bfor%2Bboats%26start%3D36%26ndsp%3D18%26um%3D1%26hl%3Den%26rls%3Dcom.microsoft:en-us:IE-SearchBox%26rlz%3D1I7GFRI%26sa%3DN

 

Wednesday, June 18, 2008 4:10:09 PM (Eastern Standard Time, UTC-05:00)  #    Comments [0] -

 Tuesday, May 13, 2008

What you need to know about your Propeller

Ok so props seem to be a simple part of your boat. They spin around and you go! Too bad that’s not the extent of them. Unfortunately, there is a lot more to props than what meets the eye. You need to make sure that you have the best prop for your boat because it will improve handling, maximize speed and efficiency, and put your power plant under minimum stress. If you are running the wrong prop, more than likely you are burning more fuel while going slower, and possibly even taking years off the longevity of your motor.

Now here is everyone’s theory… “the manufacturers put the best prop on your motor when you bought your boat.”  Don't count on it! Most manufacturers/dealers usually go with the prop that's best for the most diverse applications, because they never know if that 250-hp mill will be hung on the transom of an offshore center console, pontoon boat, or a bass boat. Funny thing is, some manufacturers don’t even supply a prop, so the dealership has to make the decision. Most likely if you are running with the original screw, chances are you are a prime candidate for a prop exchange.

Here are some prop basics for you to know before choosing your next prop.

DIAMETER is the size of your prop, expressed in inches. Diameter of propellers is measured by radius times two, with propellers you can’t take a measurement across the entire propeller, just take a measurement from the center of the propeller to the outside of one blade tip and double it.

PITCH is a hypothetical measurement that describes how far the prop will move forward through the water with one full rotation. .   It can be measured, but only by a pitchometer, basically it is a measurement of drop from one point of the blade to another.  The pitch of propeller means that for one revolution, the boat should advance the amount of pitch in inches, but remember you have to calculate out slip.

CUP is the curvature at the trailing edge of the blades. Adding cup to a prop usually increases its bite on the water, reducing slippage.

BLADE AREA is the surface area of each blade, expressed in square inches, multiplied by the number of blades. The blade area can be looked at from a bird’s eye view.  If you set the propeller on the ground and draw a circle around the propeller, the blade area is the amount of the circle that the propeller covers.  Average blade area for a common three-blade prop ranges from t 50 to 70 percent. If a prop does not have sufficient blade area, propulsion is lost.

 

When it’s time to shop for props, you will usually see them branded by pitch and diameter, expressed in inches.  Increasing pitch by an inch typically results in a drop of about 200 to 250 rpm at full throttle. A cupped prop of the similar pitch and diameter will also drag down rpm compared to a prop with no cup.

Now how many blades should you go with? The majority of common props on boats under 35 feet have three blades, which offers the best compromise between balance, efficiency, blade area, and vibration. Four-blade props are prevalent on boats that frequently encounter ventilation issues, such as tunnel hulls and powercats. They get an enhanced bite on the water when three-bladers might slip too much. The additional blade can also improve hole shot and decrease vibration. Top end, is typically cut by a couple of miles per hour, as that additional blade also adds drag. Props with less than three blades are nearly all for applications such as sailboat auxiliary motors and electric trolling motors.  As a rule, five or more blades are on large vessels or special applications.

The material a prop is made of also affects performance. Aluminum props are not nearly as expensive as the stainless steel props, but they usually flex more and are a little slower at top-end by a mile-per-hour or two. The advantage to aluminum is that if you hit an object at high speed, the softer metal bends more easily. Whack something hard with a stainless prop, and typically the first thing to give away is part of the drive train

The most efficient technique to determine if you need a prop exchange is to look at maximum throttle rpm, and make sure it is in the middle of the manufacturer's suggested range. If you have an outboard rated to turn 5000 to 5500 rpm and it turns 4900 or 5600 rpm, you have a problem.

So let’s see how to fix your problem:

How do I find the proper pitch for an RPM range?

Each engine is geared to operate within a specific range specified by the manufacturer. Taking your current propeller pitch, and the RPM's that are being generated, you can calculate which pitch to move to by the following equation:

(Current RPM / Desired RPM) x Current Pitch = New Pitch to achieve desired RPM.

Example: If you have a 21 pitch propeller, and are turning 4900 RPM, and want to go to 5350 RPM, then

(4900 / 5350) x 21 = 19.25, which is the new pitch. 

--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------

However, let's say top-end speed is the most important feature for the way you run your boat. In this case, reducing an inch of pitch will cause the rpm to the upper range of the manufacturer's recommendation, and your top-end speed ought to improve by a mph or two. However, hole shot will suffer. As with most things regarding boat performance, this is the trade-off.

If your engine over-revs from ventilating (cavitations), going from a three- to a four-blade prop frequently solves the problem. If you want to increase both top-end and cruising speed instantly, swapping an aluminum prop for stainless steel will do the trick. To decrease vibration, go from a three- to a four-blade prop.

Another cause to contemplate changing a correctly sized prop is if you run a dual-use boat. If the kids want to go water skiing from your center console (which is propped for finest cruising speed, but as an end result slow to get on plane), you might want to exchange for a prop that provides a better hole shot when you plan to spend the day water skiing.

Our point of this information is that any time you purchase a new boat, plan on trying some different props to find the one that best fits your boating needs.


                                           


                                                                                                  

                                  
Tuesday, May 13, 2008 11:16:30 AM (Eastern Standard Time, UTC-05:00)  #    Comments [0] -

 Monday, April 21, 2008

Double Taper Drive Shaft Removal

1.    Remove the propeller.

**We suggest using a prop puller to prevent damaging the propeller. Attempting

to pound off the propeller with a hammer will very likely damage the propeller and should be avoided.**

     2. Loosen the stuffing box nut.

     3. Loosen the safety collar.

     4. Unbolt the shaft coupling from the engine.

     5. Slide the drive shaft and shaft coupling away from the engine and remove the retaining                  

         nut from the end of the drive shaft.

     6. Re-bolt the shaft coupling to the engine.

     7. Attach the shaft puller, then hammer away until the drive shaft comes out of the       

         coupling.

     8. Remove the shaft coupling from the engine.

 

Single Taper Drive Shaft Removal

     1. Follow steps one through three of double taper drive shaft removal.

     2. Remove the set screws from the shaft coupling. **Do not remove the bolts    

          attaching the shaft coupling to the engine.**

     3. Attach the shaft puller, then hammer away until the drive shaft is free of the shaft    

         coupling. **Before removal, it is a good idea to mark the drive shaft with a felt tip pen where it

         enters the shaft coupling to provide an indication of progress.**

     4. Once the drive shaft is out of the shaft coupling, check the transmission coupling end of

         the drive shaft for scoring. Smooth out any rough edges or burrs to avoid damaging the

         packing seal or strut bearings when removing the shaft.

     5. Remove the drive shaft from the boat.

     6. Remove the shaft coupling from the engine.

 

Cutlass Bearing Removal

     1. Remove drive shaft.

     2. Determine appropriate bearing puller washer by measuring the OD (outer diameter) of the

         cutlass bearing.

     3. Slide puller coupler through strut (use sleeve for 1-1/8” ID (inner diameter) bearings) and

         attach appropriate bearing puller washer with bolt.

     4. Align bearing puller with cutlass bearing and hammer strut bearings out of the strut.

 

Cutlass Bearing Installation

    1. Determine appropriate bearing puller washer by measuring the OD of the cutlass bearing  

        to be installed.

    2. Slide puller coupler through strut, place cutlass bearing on puller coupler and secure with

        bearing puller and bolt. 

    3. Line up bearing with inside of strut barrel to assure correct orientation.**If cutlass  

          bearings are not pulled in straight, barrel damage may occur.**

     4. Hammer cutlass bearing through until back edge of strut bearing is aligned with shaft end

        of strut barrel.

    5. Push puller back through strut and place second cutlass bearing on the puller coupler.

        Hammer until the front edge of the strut bearing is aligned with the forward end of strut

        barrel.

    6. Remove puller from strut and re-install drive shaft.

Monday, April 21, 2008 1:26:12 PM (Eastern Standard Time, UTC-05:00)  #    Comments [0] -

 Wednesday, March 12, 2008

What do the baseball, football, and boating seasons have in common? They all have pre-seasons. 

In boating, Spring is the time to get your vessel ready for the greatest season of the year.  It is also an opportunity to avoid potential safety problems.  

The pros at Deep Blue Yacht Supply have designed a powerful playbook to help you  prepare for boating season.

Dust off the owner's manual.  Always consult your manual for specifics and for items that may deviate from this checklist.

Click here to download a printer friendly version.

Engine

  • Change the Oil
    Did you change the oil when you winterized your boat?
    Even if you did, the oil usually absorbs unwanted acids and chemicals from the engine during the long winter's sleep. You may want to change the oil again to remove these deposits.

  • Reconnect Spark Plugs
    If you left the spark plugs disconnected during the winter, it's time to re-install and re-connect. 

  • Reconnect Fuel Hoses
    As with the spark plugs, the same applies to outboard

  • Intake Sea Strainer
    Double check that the strainer is free of debris and corrosion.

  • Inspect all belts and hoses.
    Clamps should be snug and free of rust.  If they show signs of cracking, rotting, or feel mushy, it's best  to replace them now. 

    Here is a neat trick that we use to test fuel lines and clamps.  Take an old white rag and run it up and down the fuel clamps and hoses.  If you see or smell fuel on the rag, it is best to tighten the clamps and inspect the hoses more carefully.

    To replace any hoses or belts, check out our selection of Buck Algonquin® hoses and clamps.

  • Sterndrive Boot and Hydraulics:
    Inspect rubber boot for cracks or holes.
    Check fluid levels in lift pumps and hydraulic steering.
Propellers and Shafts

  • Inspect Propeller
    Remove prop and lubricate if necessary.  Inspect prop for dings or damage.  Even a slightly dinged prop can cause excess vibration on the engine / lower unit.  If ding exposes aluminum, then excess corrosion can occur from electric currents. Have propeller repaired or consider purchasing a new propeller.

    Deep Blue Yacht Supply offers the following tools:


  • Inspect shafts and struts for proper operation.
    We offer stainless steel boat shafts in Aqualoy® 17, 19, and 22 material. Please refer to our Shaft Guide for specifics about custom stainless shafting.

  • Inspect Shaft Cutless Bearings
    Replacement is due when the prop shaft starts to shimmy or when the shaft shows movement of about 3/16 of an inch. Deep Blue Yacht Supply carries a wide range of Metallic, Non Metallic, and Flanged Cutless Bearings
eLECTRICAL

  • Check water levels

  • Fully Charge the battery
    It's been sleeping for a while.

  • Clean Battery Terminals
    Remove all the corrosion

  • Inspect Electrical Connections
    Check for wear in electrical wires.  Repair if necessary.

  • Shore Power Cable
    Inspect cable for burns and wear

  • Test your electrical systems for proper operation
    • Gauges
    • VHF Radio
    • Antennas
    • GPS Units, Plotters, & Fish Finders
    • Water Pumps
    • Lighting
    • Bilge Pump
Safety & emergency

  • Inspect Life Jackets / PFDs
    Get them out of the back of the locker.  Inspect them for rips.  Double-check the seams.  Do you have enough for each person onboard?  Do you have enough sizes for younger kids? 

    Have you ever had to put on a life jacket in an emergency?  How about one that is still in the plastic?  Take out a stop watch and time yourself.  Can you put in on and adjust the straps in less than 15 seconds?  To avoid potential problems, we use the following technique for all our trips:

    Pull out your PFDs.  With a Sharpie, number each one.  When your guests board your boat, assign them a number and throw them a life jacket with the appropriate number.  Ask them to adjust the straps to their size and try it on for size.  This helps in two ways.  First, in an emergency, there will be no time messing with the straps.  Secondly, it helps get the life jackets out from the back of the locker, and closer to the surface.

  • Throwable Flotation Device
    The U.S. Coast Guard requires that you have one throwable PFD. Let's say that you throw it and miss your target.  Now what?  I keep two throwables on my boat.  One with a line attached.  In an emergency, I first throw the regular cushion.  If I miss, then I'll have the one with the line to throw over and over again.

  • Fire Extinguishers
    Make sure the extinguisher is fully charged.  In addition, the extinguisher has been sitting in its mount for a while without any movement.   To avoid the chemical from settling into a hard rock at the bottom of the canister, slowly invert the canister 20-25 times.  You should feel the chemicals slosh back and forth through the canister.

    Lastly, if the expiration date has passed, or is coming due, it would be best to buy a new fire extinguisher.  If you can find an ABC extinguisher, I would definitely pick one up.

  • Flares / Visual Distress Systems
    Check the expiration date on your flares.  42 months is the usual life of flares.  If the flares have expired, you can donate them to your local USCG Auxiliary Flotilla or Fire Department. 

  • Re-organize your emergency box
    By re-organizing your emergency kit, you'll see if something has gotten wet, or if something has expired. If you don't have a kit, it's time to buy one.  I keep a fully stocked waterproof box onboard. 
    Here are some of the items that we store in the box.
    • First Aid Kit
    • Screwdrivers
    • Vise-Grips Pliers
    • Spare Navigation Bulbs
    • Spare Spark Plugs
    • Spare Fuses
    • Flares
    • Extra Knife
    • Extra Batteries
    • ...and even more batteries

  • Check your compass
    What if your GPS unit loose powers.  This is your non-electrical friend.

  • Liferaft Inspection
    Is it time for servicing?  Please use a local facility or your OEM for this one, as they can repack it properly.

    Have the liferaft supplies expired? Are they still in good condition?

  • Test the Smoke Detectors

  • EPIRBs
    Check expiration date.  Use the manufacturer to replace batteries. 
    Register unit with USCG.   Follow manufacturer's instructions on how to test.

  • Abandon Ship / Ditch Bag
    You hope it never happens, but just in case.  Here are a few items worth considering.
    • EPIRBs
    • Sea-Dye Packet
    • Handheld VHF Radio
    • Flashlight
    • Batteries
    • Watertight Bag for Electronics
    • Flares
    • Whistle
    • Passports
    • Protein or Granola Bars
    • Water Packs, Water Maker, Desalinization Packs
    • Water Container
    • Inflatable Distress Flag (can catch rain water, too)
    • Fishing Line / Hook / Sinkers
    • Sunscreen
    • First Aid Kit
Deck / Hull
  • Bow
    Inspect the lifelines, pulpits, and stanchion. Inspect the anchor, ground tackle, lines, and fenders.

  • Hardware
    Inspect all deck hardware including cleats, deck pipes, hatch lifts, brackets, vents, and scupper plates for damage or wear.

    If you are in need of deck hardware, check out our wide selection of Buck Algonquin® Marine Hardware.

  • Inspect dingy and life raft clamps

  • Inspect bimini canvas and covers

  • Inspect Hull for Damage
    Look for and repair any scratches and gouges. Inspect for blisters.

  • Inspect Trim Tabs
    Be sure to test the trim tabs to make sure they function properly. Refer to your owner's manual for specifics.

  • Replace Zincs
    These sacrificial pieces of metal protect the precious metal components of your boat including lower units, propellers, rudders, shafts, and struts. They should be replaced when one-third of the original zinc remains. I like to replace mine once a season when the boat is out of the water.

    Be sure to check out our wide array of Zimar Zinc Anodes.

  • Inspect Rubber Gaskets and Seals
    Renew caulk and gaskets.  If in doubt, you should replace.

  • Inspect rudder / steering components and fittings.
    Deep Blue Yacht Supply provides a wide range of Steering Components.

  • Inspect Drain Plug
Fresh Water System

  • Fill the water tanks

  • Reconnect the hot water heater

  • Non Toxic Antifreeze
    Although it's non-toxic and alcohol based, nobody likes it.  Flush out the antifreeze that you added in the winter.  Run all the faucets including the shower heads.
Bilges

  • Verify that bilges operate properly
    Verify connections to battery. Clear debris from float.

  • Make sure bilge has oil
Documents

  • USCG Auxiliary Safety Check
    The Coast Guard Auxiliary performs complimentary safety checks. This helps confirm that your vessel meets both Federal and State regulations.  There are no citations issued and violations are not reported to law enforcement. 

    Visit SafetySeal.net to locate an examiner in your area.

  • Check you boat's registration

  • Insurance Policy
    While your insurance company will usually send you the renewal bill, use this time to make sure your coverage meets your needs.

  • Boat Towing Service
    Is it time to renew your service?

 

Wednesday, March 12, 2008 4:36:55 PM (Eastern Standard Time, UTC-05:00)  #    Comments [0] -

 Sunday, March 02, 2008

What makes up the shaft seal?

 

A mechanical seal is created by the contact of a turning surface against a stationary surface. In the case of the PSS Shaft Seal, the stationary surface is a carbon flange held in contact against a stainless steel rotor which turns with the shaft. The carbon flange is attached to the boat by a nitrile bellow which, with the help of water pressure, produces a constant contact between the carbon and the stainless steel ring. These type of seals are unaffected by engine motion or vibrations. The result is a 100% watertight and totally maintenance-free seal. 

1) HIGH DENSITY CARBON/GRAPHITE FLANGE
This space age composite is machined to shape. The face is then lapped to 4 light bands. Once installed and operational the carbon/graphite face will actually polish the stainless steel rotor face during the initial minutes of operation. This polishing process ensures a perfect seal and eliminates the necessity of a spray guard. The high density of this composite greatly increases its impact and wear resistance. At a maximum operating temperature of 500° F, the carbon guards against any overheating situation unlike other seals using plastic derivatives. The carbon/graphite flange should never need replacing under normal operation conditions.

2) DOUBLE O-RINGS
The nitrile O-Rings are fit inside the stainless steel rotor to guarantee alignment and seal of the rotor to propeller shaft. Nitrile is the material used due to its superior resistance to petroleum products, temperature variations and resistance to tearing. These O-rings are stationary and do not wear.

3) STAINLESS STEEL ROTOR
The one-piece stainless steel (Type 316) rotor is slid down and secured to the propeller shaft with double set screws. Precision tolerance are maintained bycomputer controlled lathes. After machining, the rotors are passivated to military specifications for maximum corrosion resistance. The stainless steel rotor should never need replacing under normal operating conditions.

4) DOUBLE ALLEN HEAD SET SCREWS
Allen head set screws with cupped ends (to prevent damage to shaft) are threaded into the rotor and secured to the propeller shaft. A second set screw is then threaded into each hole to secure the first screw and to prevent it from possibly backing out. Set screws are treated with a Dri-Loc 204.

5) DOUBLE HOSE CLAMPS
Two stainless steel hose clamps are used to secure the bellow at both the stern tube and flange ends.

6) BELLOW
Bellow is resistance to petroleum based products and set retention. It provides the best combination of durability, strength and elasticity. The stern tube end of the bellow is available in 1/4" increments. Both shaft and stern tube diameters are necessary when ordering.

Sunday, March 02, 2008 9:17:28 PM (Eastern Standard Time, UTC-05:00)  #    Comments [0] -

Boat Propellers, Cutlass Bearings, Zinc Anodes - Deep Blue Yacht Supply
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The opinions expressed herein are my own personal opinions and do not represent my employer's view in any way.

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