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Seakeeper 18 Installation Manual (90672-2); S/N 18-234-2475 to Current

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Seakeeper 18 Installation Manual (90672-2); S/N 18-234-2475 to Current

2.4 Bolt-In Installation

2.4.1 Preparation of Hull Structure

Refer to Seakeeper Drawing No. 90544, Seakeeper 16/18 Installation Details – Bolt in Method. Important dimensional and load information is given in this drawing that will impact the design details of the structure that will receive the Seakeeper. It is assumed that a proper structural analysis has been performed for the hull structure to which the Seakeeper will be fastened to ensure proper strength margins for the loads the Seakeeper will create during operation. Seakeeper recommends a safety factor of 3.0.

The hull structure supporting the Seakeeper should be arranged so the Seakeeper is parallel to the waterline in the transverse direction and within 2 degrees longitudinally.

In addition, the four areas on top of the structure on which the Seakeeper 18 frame and isolation gaskets will rest need to be co-planar within .06 in. (1.5 mm) to minimize potential distortion of Seakeeper support frame when installed.  The isolation gaskets are only used when the Seakeeper 18 is mounted to a dissimilar metal structure.

Seakeeper provides an installation template kit, P/N 90282, which contains plates that match the mating surfaces of the four feet located on the Seakeeper’s frame. These plates have 4 holes located at the same centers as the mounting holes on the Seakeeper. The fixture locates the hole patterns at the proper spacing both in the fore-aft direction and the port-starboard direction, see Figures 7. Once assembled, the fixture can be used to check clearances and alignment of the hull structure.

Note:   Do NOT use the installation fixture to establish the Seakeeper envelope dimensions.  Refer to Drawing No. 90544 for envelope dimensions. A 3-D model of the Seakeeper is available on the Seakeeper Technical Library (www.seakeeper.com/technical-library/)  to aid in designing the Seakeeper foundation and the space around the Seakeeper.

NOTE: MAKE SURE NO OBSTRUCTIONS FROM THE HULL STRUCTURE CAN BE SEEN WITHIN THE INSIDE OF THE INSTALLATION TEMPLATE KIT (INSIDE THE MARKED RED LINES) AS SEEN IN FIGURE 7. REFERENCE SEAKEEPER DRAWING NO. 90544.

Figure 7 – Installation fixture (90282)

CAUTION: Tight clearances from cable guide bands to hull structure.
See above figure for dimensions and reference
Seakeeper Drawing No. 90554 for complete Seakeeper 18 envelope

2.4.2 Transfer of Holes to Boat Structure

  1. Lower assembled fixture onto hull structure (See Figure 8).
  2. The four areas where the feet of the Seakeeper will rest should be coplanar to within 0.06 in. (1.5 mm). See figure to the right.
  3. Align fixture in desired location and transfer holes from fixture plate to the hull structure.  Note that holes in fixture plate are ø0.55 in. (14 mm).
Figure 8 – Positioning Installation Fixture over Hull Structure

2.4.3 Blind Hole Installation

  1. Remove Template Fixture and drill four (4) x 9/16 in. ø (14.29 mm ø) holes perpendicular to the vessel structure to a minimum depth of 0. 84 in. (21 mm). Take special care to drill perpendicular to mounting surface.
  2. Tap drilled holes for M14-2.0 threaded inserts.
  3. Install four (4) M14-2.0 X 1.5D (21 mm length) locking threaded inserts into holes in hull structure at drilled and tapped locations using threaded insert manufacturer provided installation tool.
  1. Remove threaded insert prong / tang after threaded inserts are installed

2.4.4 Through-Hole Installation

  1. Remove Template Fixture and drill sixteen (16) (15mm ø) holes perpendicular to the vessel structure. Take special care to drill perpendicular to mounting surface. A drill guide is recommended.

2.4.5 Installation of Seakeeper

  1. Lower Seakeeper into position onto the hull foundation beams and align over drilled holes. Apply a small bead of marine sealant (e.g., SILI-THANE 803 or equivalent) between mating surfaces of Seakeeper frame and hull structure to prevent moisture wicking into bolt holes.
    1. For dissimilar metal foundations locate and position 4 isolation gaskets onto foundation beams and apply a small bead of marine sealant (e.g., SILI-THANE 803 or equivalent) between both mating surfaces of each isolation gasket where it contacts the beam and the Seakeeper.
  1. Install mounting bolts:
    1. For Blind-Hole installations (Seakeeper Kit #90548), install the Seakeeper supplied Grade 10.9, M14-2.0 x 100 mm fasteners or alternative Grade 10.9, M14-2.0 bolts to maintain a minimum thread engagement of .82 in. (21 mm). Apply a moderate coat of nickel-based anti-seize (e.g., SAF-T-EZE nickel grade anti-seize, SBT-4N or equivalent) to the threads of each bolt and include a small bead of marine grade sealant (e.g., SILI-THANE 803 or equivalent) under each bolt head and washer before installation.
    2. For Through-Bolt installations (Seakeeper Kit #90648), install the Seakeeper supplied Grade 10.9, M14-2.0 x 120 mm fasteners or alternative Grade 10.9, M14-2.0 bolts to maintain a minimum of 2 threads protruding past nut. Apply a moderate coat of nickel-based anti-seize (e.g., SAF-T-EZE nickel grade anti-seize, SBT-4N or equivalent) to the threads of each bolt and include a small bead of marine grade sealant (e.g., SILI-THANE 803 or equivalent) under each bolt head and washer before installation.
Figure 9 – Bolt-In and Through-Bolt Details of Installation
  1. Torque all fasteners to 100 ft-lbs (136 Nm).
    1. New bolts, matching the Seakeeper specification, must be used for each installation and reinstallation that meet the requirements listed above.
  2. Proceed to electrical and cooling portion of the installation.
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