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Owners Manual (New)


         In-board engine installations on sailboats differ from engine installations
         on power boats. The primary difference is that the engine is usually
         installed below the waterline of the vessel.

         The benefits of these locations are that the weight of the engine
         is where it will not adversely effect trim, and that the shaft
         is at an efficient angle for powering and minimum drag when sailing.

         Engine installations below the waterline require special attention
         to the design of the exhaust system. The discharged cooling water
         must be exhausted above the waterline to avoid excessive back pressure
         on the engine and prevent sea water from traveling up the exhaust
         line and entering the engine.

         To exhaust the engine above the waterline, the discharged cooling
         water and exhaust gas must be "lifted" to a level above the through
         hull fitting on the transom.

         In the Catalina 25, the exhaust cooling water and exhaust gas are
         lifted above the waterline by an "aqua-lift" type muffler. The
         aqua-lift muffler performs three jobs:

         1.    It mixes engine gas and water to cool the gas and lower
               exhaust line temperature.

         2.    It baffles and deadens engine exhaust noise.

               It creates pressure required to lift and expel cooling

         As shown in illustration 4.4.8 the inlet tube into the aqua-lift
         is short and the outlet tube is long near the aft of the tank.

         As the water accumulates in the bottom of the tank, exhaust gas
         pressure builds in the top of the tank. This forces the cooling
         water up the exit tube and through exhaust line overboard.

         The system requires exhaust pressure in the tank to function.
         When the starter motor is turning over, before the engine fires,
         water is being pumped through the cooling system by the belt driven
         cooling water pump. It is very important not to operate the starter
         motor for more than 30 seconds if the engine does not fire. Should
         it be necessary to operate the starter motor more than 30 seconds.
         water must be drained from the aqua-lift by opening the drain at
         the base of the aqua-lift.

         The drain valve may be opened until the engine fires, if desired.
         All Catalina 15's are equipped with anti-siphon valves as an additional
         precaution to prevent cooling water from entering the engine.

         Refer to item "B" of illustration 4.4.8. The function of the anti-siphon
         valve is to prevent cooling water from being siphoned through the
         through hull valve, through the engine cooling system and into
         the aqua-lift muffler when the engine is not operating.

         If the muffler were to fill completely with water, water would
         travel up the inlet tube and enter the engine block.

  The Catalina 25 exhaust system is basically simple and will provide
  trouble free service if you perform regular maintenance and inspection.
    The important points to remember are:

1.    Close the engine cooling water through hull valve when
      you are not operating the engine.

2.    Do not operate the starter motor for more than 30 seconds
      without draining the aqua-lift muffler.

3.    periodically disassemble the anti-siphon valve. Be sure
      the valve is not fouled with salt deposits and that it
      opens freely under the cap.

4.    Check the operation by removing the valve:

      A.  Put a finger over one large hole and blow through
          the other. Air should not escape through the cap.

      B.  If you suck through one large hole with a finger over
          the other. air should enter the Valve through the

5.    Check the flapper valve on the transom. This prevents
      water from surging up the exhaust line in a following sea.
      Replace the flap as required to maintain function.

4.4.8 Picture


    The packing gland is located under the quarter berth.

    A properly adjusted shaft packing gland should drip slightly (from
    4 to 10 per minute) with the engine off. Too loose an adjustment
    will allow too much water in the bilge and engine operation will
    spray water from the shaft. Too tight an adjustment will rob the
    engine of power and the lack of water lubrication in the packing
    gland can generate enough heat to damage the gland and/or score
    the propeller shaft.


    1.    Holding the packing nut with one wrench, use a second wrench
          to loosen the lock nut. Turn the lock nut far enough to
          keep it from interfering with the next adjustment (2 or
          3 turns).

    2.    Tighten the packing nut to obtain 4 to 15 drops per minute.
          Band tightening of the packing nut is often sufficient
          to obtain this adjustment. If this is not the case. an
          additional 1/4 to 1/2 turn with the wrench should produce
          the desired result.

    3.    Hold the packing nut in place with one wrench, and use
          the second wrench to bring the locking nut securely against
          the packing nut. Make certain that the locking nut is
          tight. Failure to do this could allow the packing nut
          to back off when the engine is operating.

    4.    Operate the engine at slow speeds in forward and reverse
          and use a light to check for excessive water at the packing
          nut. Shut off the engine and recheck packing for proper

         For proper operation of the engine. the propeller shaft and engine
         must be aligned.

         Alignment is gauged at the engine and shaft coupling. Alignment
         procedures must be done with the boat in the water after the mast
         is erected, and the rig is tuned.

         1.     The propeller shaft must be dimpled (1/8' deep) for two
                (2) coupling set screws. The set screws must be safety
                wired using the stainless steel wile provided, as illustrated
                check key in key way, as it must be in place between shaft
                and coupler.

         2.     Remove coupling flange bolts and check propeller shaft
                for clearance. Adjust stuffing box to prevent excessive
                seepage, yet allow shaft to spin freely.

         3.     Slide shaft away from engine and check coupling mating
                surfaces. These surfaces must be clean.

         4.     Slide shaft forward to connect coupling surfaces.
                Pilot on transmission flange must align with recess in
                shaft coupling flange. This is an indication of correct
                axial alignment.

         5.     With coupling flanges in contact, measure gap around edge
                of coupling flanges with.003 feeler gauge. Maximum allowable
                gap at any point is three thousandths of an inch. Take
                this measurement several times....rotating shaft 1/4 turn
                each time. Any gap in excess of .003 must be corrected
                by changing engine position, especially fore/aft tilt.

                For example. excessive gap at the bottom of the coupling
                (see drawing) indicates engine is tilted too far aft (front
                too high). Using a 15/16 end wrench. loosen lock nuts
                on forward motor mount(s). Lower front of engine by clockwise
                rotation of motor mount nuts. Re-measure gap at coupling.
                A gap at the top of the coupling would require the exact
                reverse procedure.

         6.     Pull shaft backwards as in step 3. Again slide shaft forward,
                rechecking axial alignment as in step 4.

         7.     Repeat steps 5 and 6 until alignment within tolerance is

         8.     Tighten motor mount lock nuts and install coupling bolts.

         NOTE:  Alignment should be checked yearly. or whenever any excess
                vibration is noticed. The alignment can also be affected
                by changes in rigging tension.

4.4.11 Picture

4.5.1 Picture


       There is provision for a gimballed stove on the port side of the
       galley area. A two-burner alcohol stove is the factory installation.
       It comes with an operation and maintenance booklet provided by
       the stove manufacturer. A compressed natural gas stove is available
       as a factory option. Follow the instructions for operation carefully
       when using the stove. Although compressed natural gas is among
       the safest of cooking fuels, extreme caution should be used when
       cooking aboard, or handling compressed natural gas fuel tanks.

       When filling and lighting the standard alcohol stove, please observe
       the manufacturer's instructions. It is good practice to have a
       fire extinguisher within safe reach of the galley. Alcohol fires
       can be extinguished with water so it is wise to keep a filled bucket
       or container within reach of the cook.


       If your boat is equipped with a "pop top" hatch. the following
       notes will aid in its operation.

       First of all. the pop top can be used in two different positions.
       When the pop top is in the down position, the smaller sliding hatch
       serves as access to the cabin. When the pop top is in the up position.
       access to the cabin is greatly increased and, of course, so is
       the available headroom. To put the pop top in the up position
       you must go inside the cabin. The top is raised by lifting upward
       and forward at the same time. With the pop top in the fully raised
       position, reach forward to the pop top slide lock and lock the
       top to the mast.

       Do not sail or motor your Catalina 25 with the pop top in the raised
       Always lower and lock down the pop top in rough weather. When
       lowered. the pop top should be locked down using the lock down


    The Catalina 25 is an easy boat to trailer when certain precautions
    have been properly heeded. The following suggestions will prove

    1.    Be sure to read the trailer manufacturers instructions
          and warranty carefully, and do not exceed the manufacturers
          gross vehicle weight far trailer boat and gear.

    2.    Check tongue weight. Most trailers tow well with 7 to
          10 percent of the gross trailer and lost weight on the
          tongue. If the trailer tends to "fish tail· add tongue
          weight by moving weight forward or the trailer axles aft.

    3.    Test the brakes by operating the master cylinder manually.

    4.    Inspect the winch cable for broken strands or fraying.

    5.    Tie the mast and boom securely to the bow and stern pulpits,
          the spars should also be supported in the middle by the
          cabin top. Pad the mast at all contact points to prevent

    6.    Boats should be seated properly on the trailer: that is.
          not ajar or tilted, and with the bow properly snugged into
          the rubber wedge at the front of the trailer. Boats should
          have the weight of the boat bearing on the keel, not the
          padded upright supports.

    7.    Follow normal trailer procedures of connecting lights and
          safety chain, and be sure your hitch is well secured.
          Always test lights before leaving ramp area.

    8.    Do not allow anyone aft of the transom during launching
          or loading, who could be injured if the boat were suddenly
          dislodged from the trailer.