Refit of S/V Jean Marie
Engine Refit - Part 1
by 
Jean Service & Capt. Tom Service

The overhaul of S/V Jean Marie’s Machinery Space was a complete refit of all hull, mechanical, and electrical systems contained within the engine room and main bilge sump.  This picture was taken from the stbd fwd corner of the cockpit with the stbd hatch removed.

The old engine and all of the electrical and plumbing systems were removed, and the machinery space was completely gutted.

The as-built machinery space had open voids between the water tanks and the adjoining structures, and open communication with the aft cockpit locker and aft head.  These openings, which were effective paths for engine noise into the accommodation, were closed in with plywood.

The bulkheads and exposed tank surfaces were bare and reverberated the engine’s noise.  To attenuate this noise GSI Sound-Stop 1" thick acoustic insulation was installed on all vertical surfaces and the overhead.

The new engine is a Perkins Prima M60 diesel, a 500 series industrial engine marinized by Detroit Diesel.  The 4 cylinder, naturally aspirated, M60 has the following specifications: 3.33" X 3.50" bore & stroke, 122 cu in displacement, 18.1:1 compression ratio, 59 BHP @ 4000 RPM gross power, 57.5 SHP @ 4000 RPM net power, 501 lbs (weight includes transmission).  The marine gear is a Hurst HBW250 2.74:1 ratio transmission.

The new engine is smaller than the old, and we designed and had fabricated engine mounting brackets to securely attach the engine mounts to the boat’s engine ways.  The stbd engine brackets are visible in this picture.  We do not intend to turn S/V Jean Marie keel up, but if we do, these brackets will keep the engine in place.

The original CSY-44 design philosophy produced walkover mid-cockpit models for the Caribbean charter boat business.  This picture illustrates some of the advantages that a separate accommodation layout, originally designed to provide privacy for charter couples, provides mom & pop bluewater sailors.  These advantages include; efficient sailing profile (lower freeboard and windage), easy access to machinery for repair and maintenance, cruising independence through increased liquid load capacity (400 gal water, 100 gal fuel), machinery noise and smells isolated from the accommodation, the machinery room fwd and aft bulkheads strengthen the critical hull/deck girder amidships, and a desirable level of privacy between the fwd and aft cabins (important when cruising with children or guests).  Contrary to today’s mass-market "waterfront apartment" approach to boat design, we think this walkover layout is ideal for long distance bluewater cruising.

This view is from the main cabin door located in the stbd side of the machinery space fwd bulkhead.  This door gives access to the machinery space without opening the cockpit deck hatches (especially important during heavy weather offshore).  The port cockpit deck drain hoses can be seen behind the engine.

The aft vertical silver surface is the fwd side of the fuel tank.  Note the black rubber bilge baffle fitted under the fuel tank to attenuate and isolate engine and refrigeration equipment noise from the aft accommodation.  The fwd and aft engine room bulkheads are baffled with these heavy rubber flexible skirts on both sides of the bulkheads.

This is a view of the bilge area immediately aft of the engine on the port side of the machinery space.

The bilge surface has been filled, faired, and coated with 2 applications of high build epoxy primer, and finished with 2 coats of white epoxy paint.

All of the seacock backing plates and thru hulls in the machinery space were replaced.  Shown is the port cockpit drain seacock.

The Vernalift wet exhaust system was sized to contain the backwash from the 2" exhaust hose that is goosenecked into the top of the port cockpit coaming.

Part of the aft bilge baffle is visible in this view of the bilge.

The engine’s seawater intake strainer was positioned aft for accessibility, and to ensure a positive slope between the seacock and the engine raw water pump.  The old installation had the strainer too high, and was prone to ingesting and trapping air in heavy weather or high angles of heel.  S/V Jean Marie is equipped with an automatic angle-of-heel warning system (If the angle-of-heel exceeds approximately 12 to 15 degrees, a stern female voice exclaims from the galley "Set this boat up right now if you ever want to eat again!").

This is the aft-port-outboard-upper corner of the machinery space; we call it the water line thru-hull annex.  It was a real challenge working in this small, difficult to access area.  In the as-built configuration this area was open to the aft head bilge and the port cockpit coaming.

All of the WL overboards (refrigeration condensate cooling water, main electric bilge pump discharge, and manual bilge pump discharge) are goosenecked into the very top of the port cockpit coaming before they exit the hull.

As Tom moves into his 50’s, he needs more light to see what he is doing than when he was younger.  In addition to the existing CL dome light, we added 2 more lights aft to illuminate each side of the machinery space.  These lights, along with the reflective Mylar surface on the acoustic insulation, and the white bilge, really brighten up the engine room.  Now Tom can see what he is doing (after Jean tells him where he laid down his reading glasses).

The area over the top of the fuel tank was open to the aft cockpit locker.  Closing this in really quieted down the engine noise in the cockpit.

Note the SS wire rope run from the overhead to the lifting eye on the engine block to provide support for the engine wiring harness.  This is particularly useful while in the machinery space UW, when it is all too easy to grab the wrong thing when the boat is jumping around.  All wiring is bundled and run in corrugated black plastic conduit.  Wiring runs are lead in from the overhead, minimizing exposure to the potentially wet bilge area.


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