Design Brief & Intent 1
The core mission of the Endeavour 40 was to maximize living space and comfort without presenting an intimidating profile on the water. Bob Johnson designed the hull with a beam of thirteen feet that is carried well aft, creating a massive, high-volume interior that owners famously equate to a compact floating apartment. The center-cockpit layout was positioned slightly farther aft than on comparable cruisers of the era. This preserved a dry, secure command position while avoiding the boxy aesthetic of many mid-cockpit designs.
Below deck, the boat’s cruising intent is immediately apparent in its warm, rich cabinetry and joinery. Endeavour utilized varnished teak bulkheads and structural trim balanced by soft, light overheads to prevent the deep interior from feeling cavernous. The cabin sole features a distinctive block-pattern teak parquet, bonded to a robust grid of floor timbers. The layout is optimized for dual couples or family cruising: a cozy forward V-berth cabin has direct access to a semi-private forward head and hanging locker, while the walkthrough to starboard leads past a dedicated navigation station and electrical panel. To port, a step-down galley is tucked securely out of the companionway traffic. This U-shaped culinary space boasts deep double sinks, extensive counter space, and heavily insulated refrigeration. The master stateroom aft is the crown jewel of the layout, offering an athwartships queen-sized berth, multiple hanging lockers, and a private en-suite head with an integrated shower.
Variations & Configurations
Throughout its production run from 1981 to 1985, during which approximately 185 hulls were constructed, the Endeavour 40 was offered with three distinct sail plans: a masthead sloop, a cutter, and a ketch. The ketch rig is a highly specialized variant that provides a versatile, easily managed split sail plan preferred by short-handed cruising couples. Structurally, the main mast is keel-stepped through the cabin top, while the mizzen mast is deck-stepped onto the cockpit bridge deck, supported by a heavy compression post immediately below 6.
Beyond the rigging configurations, Endeavour produced two distinct build profiles tailored to different markets. The Owners model featured a taller masthead rig, an inner forestay for a staysail, extended genoa tracks, and upgraded winches to optimize windward sailing performance and heavy-weather options. Conversely, the Charter model featured a shorter, simplified rig with fewer winches, designed specifically to reduce sailing complexity and minimize maintenance for bareboat charter operations. Both models were offered with a standard five-foot draft, utilizing a modified fin keel and a robust, skeg-hung rudder to allow safe navigation through the shallow waters of the Florida Keys and the Bahamas.
Sailing Performance & Handling
The physical realities of the Endeavour 40's design are starkly reflected in its technical ratios. With a displacement of 25,000 pounds and a waterline length of 32 feet, the boat carries a displacement-to-length ratio of 340.6. This places her firmly in the heavy displacement category. She is not a light-air flyer; in light winds under ten knots, she can feel sluggish and will require the engine or a cruising spinnaker to make decent headway. However, once the breeze fills in, this heavy displacement enables the hull to power through head seas and choppy waters with a remarkably smooth, steady motion.
This comfortable behavior is quantified by a comfort ratio of 36.89, indicating a slow, gentle roll period that prevents crew fatigue on long passages. Her ballast-to-displacement ratio of 36.0 percent, provided by 9,000 pounds of internal lead encapsulated within the keel, ensures excellent stiffness and a high righting moment. This allows the boat to carry her canvas long after lighter cruisers have had to reef. The ketch rig further enhances handling, with a sail area-to-displacement ratio of 15.94. While moderate, this split rig allows for highly versatile sail configurations. Sailing under jib and jigger (the headsail and the mizzen) is a highly effective way to comfortably handle sudden squalls or heavy weather without the physical strain of reefing the mainsail. Safe ocean-going capabilities are further verified by a capsize screening ratio of 1.78, which sits safely below the critical offshore threshold of 2.0.
Market Snapshot & Economics
On the brokerage market, the Endeavour 40 Ketch commands an enduring appeal, trading as a premium, value-dense cruiser. Its immense volume makes it a perennial favorite for liveaboards, but buyers must approach listings with an analytical eye. The economics of owning an Endeavour 40 are heavily influenced by whether prior owners have tackled the boat's primary structural issues 10.
An un-refitted model will trade at a discount, but will immediately demand a significant financial investment in structural and mechanical restoration. Conversely, vessels that have already undergone documented tank replacements, deck recoring, and engine overhauls command a substantial premium. These updated boats represent highly stable assets that retain their value exceptionally well, as the cost of commissioning these refits from scratch often equals or exceeds the raw purchase price of the boat itself.
Known Issues & Triage
Any serious investigation into the Endeavour 40 must begin with its most notorious vulnerability: the encapsulated keel tanks. The factory-installed 75-gallon aluminum fuel tank and 93-gallon aft water tank were set deep inside the hollow keel cavity and encapsulated with expanding polyurethane foam. Over decades, bilge water inevitably seeped into this foam, trapping moisture directly against the aluminum. This led to severe crevice corrosion, resulting in pinhole leaks that allow fuel to escape into the bilge or fresh water to become contaminated. Triaging this issue is a top-priority inspection item; look for diesel odors in the cabin, fuel slick in the bilge, or a history of tank abandonment. Replacing these tanks is a major, labor-intensive structural job. It typically requires cutting out sections of the teak parquet sole in the main salon and slicing the old aluminum tanks into small pieces to extract them through the companionway, although some yards have opted to cut access windows through the fiberglass hull of the keel on the hard.
Another age-related concern is deck core delamination. The deck and cabin top utilize a cored construction utilizing squares of marine plywood 12. While these block-pattern cores were designed to restrict water migration, decades of neglected re-bedding of stanchions, handrails, genoa tracks, and hatches can allow moisture to penetrate, leading to localized rot and soft spots. Particular attention should be paid to the mast partner area, which is subject to high structural loads and can develop hairline gelcoat fractures that let water into the core. Additionally, the stainless steel chainplates are through-bolted to fiberglass-encapsulated marine plywood knees. Water leaking from neglected deck chainplate seals will migrate directly into these knees, causing the plywood core to rot and threatening the structural integrity of the rig. Finally, the cockpit sole drains through a large transverse "torpedo tube" pipe that relies on rubber check-valve flaps. If these flaps have rotted or hardened, seawater can back up, flooding the cockpit sole when sailing on a deep heel.
Modernization & Upgrades
Modern owners of the Endeavour 40 Ketch have focused their refit budgets on overcoming the model's historical shortcomings while preparing the boat for off-grid cruising. Replacing the failed aluminum keel tanks is almost universally solved by installing custom-fabricated fiberglass/epoxy tanks built directly into the keel cavity, or by dropping in custom-molded high-density polyethylene plastic tanks, which permanently eliminates future corrosion worries 11.
Mechanically, the original Perkins 4-108 diesel engine—a legendary but noisy and leak-prone workhorse—is frequently replaced during major refits 13. Popular repower choices include modern Yanmar or Beta Marine diesels in the fifty-to-sixty horsepower range, which offer much cleaner operation, significantly reduced vibration, and superior fuel economy.
Cruising owners are also overhauling the boat's electrical systems. By installing custom stainless steel solar arches at the stern that double as robust dinghy davits, owners can mount large solar arrays generating between 400 and 900 watts. This green energy is typically directed into high-capacity Lithium Iron Phosphate house battery banks, often ranging from 400 to 800 ampere-hours. When paired with high-output alternators, smart regulators, and modern inverter-chargers, this setup renders noisy diesel generators obsolete, allowing the boat to run refrigeration, watermakers, and even air conditioning entirely off the sun.
The Verdict
The Endeavour 40 Ketch remains one of the premier classic cruisers for sailors seeking maximum liveaboard comfort, structural stiffness, and predictable offshore handling on a budget. While it is not a performance racer and requires a vigilant eye during the survey process to identify tank and core issues, a well-maintained or properly refitted example represents a highly capable, sea-kindly home that can confidently carry its crew to any corner of the globe.
Pros:
- Immense interior volume with a highly liveaboard-friendly two-cabin, two-head layout.
- Excellent motion comfort and sea-kindly handling in heavy seas due to heavy displacement.
- Highly stable and stiff under sail with an encapsulated keel and a low capsize risk.
- Highly versatile and easily managed split sail plan on the ketch rig for short-handed crews.
- Solid hand-laid fiberglass hull construction below the waterline with no core to rot.
- High probability of expensive, labor-intensive keel-mounted fuel and water tank failures if not already replaced.
- Slow performance in light air and poor pointing ability to windward.
- Potential for hidden rot in the plywood-encapsulated chainplate knees and deck core.
- The cockpit can receive seawater backflow through aging "torpedo tube" drain check-valves.
