O'Day 27

1972–1979 · designed by Alan Gurney · built by O'Day Company

The O'Day 27 was designed by Alan Gurney as an affordable, family-oriented coastal cruiser and weekend boat for the American market. It prioritized simplicity, ease of handling, and low cost of entry over offshore capability. The boat built a strong following among new sailors and budget-conscious coastal cruisers throughout the 1970s. It is a moderate-displacement, shallow-draft fin-keel design suited to protected and semi-protected waters.

This is a general read on the O'Day 27 class — informed background, not a verdict on any individual boat. Condition, refit history, and how a particular hull was sailed and stored matter far more than class reputation. Use it to know what to look for; for a read on a specific listing, run a free FairKeel report on that boat.

At a glance

Hull form: Fin Keel
Ballast type: Encapsulated Lead
Rudder: Skeg Hung
Mast step: Deck Stepped
Hull construction: Fiberglass
Production: 1972–1979
Built in: United States

What the O'Day 27 is known for

Shallow draft makes the boat accessible to a wide range of anchorages and tidal waters where deeper-keeled cruisers cannot go.
Simple rig and moderate displacement make the boat easy to handle short-handed, with modest sail area that new sailors can manage safely.
Low purchase price and wide parts availability keep entry cost and routine maintenance expenses accessible compared to most cruising alternatives.
Large active owner community in the US means practical knowledge, spare parts, and class-specific guidance are readily found online.

Known trade-offs

Deck-stepped mast requires a strong compression post and makes rig inspection more involved; the post can hide hidden rot or delamination in aged boats.
Balsa-cored deck is a near-universal maintenance liability on boats this age — finding a dry, structurally sound deck is the exception, not the rule.
Internal (encapsulated) lead keel means no keel bolts to maintain, but grounding damage that breaches the glass skin can let water into the keel cavity — a harder problem to diagnose and repair than re-bedding an external keel.
Cabin volume and headroom are genuinely limited even for a 27-foot boat, restricting the boat's utility for extended or comfortable cruising use.
Low market value relative to refit costs means that a boat needing significant work (engine repower, deck recore, standing rigging) can easily absorb more than the boat is worth.

Age-related quirks to expect

Osmotic blistering on hull bottom severity: Medium affects: 1972-1979

Balsa core deck delamination and rot from fastener and hardware penetrations severity: High affects: 1972-1979

Original Universal or Atomic 4 gasoline engine at or beyond service life severity: Medium affects: 1972-1979

Chainplate backing plate corrosion and tabbing failure severity: High affects: 1972-1979

Standing rigging original or long-overdue replacement on older examples severity: Medium affects: 1972-1979

Systems to check before you buy

Deck core and hardware bedding priority: coastal, liveaboard, weekending

Balsa-cored decks are vulnerable to water intrusion at every chainplate, stanchion base, and deck fitting. Soft spots underfoot and delamination are extremely common on boats this age. Probe all hardware with a moisture meter and tap the deck systematically.

Encapsulated keel cavity and keel-to-hull rounding priority: offshore, coastal, liveaboard

The O'Day 27 carries an internal (encapsulated) lead keel — there are no external keel bolts to inspect. The relevant concerns are water intrusion into the keel cavity (grounding damage that cracks the glass skin lets water sit on the ballast) and stress cracking at the keel-to-hull rounding on older hulls. Inspect for prior grounding repairs, weeping or staining at the keel sump, and gelcoat cracks along the keel root.

Chainplates and standing rigging attachment priority: offshore, coastal, weekending

Chainplate backing plates and tabbing are a known failure point. Any sign of rust staining on the cabin headliner near chainplates warrants removal and inspection. Original wire rigging on boats over 20-25 years old should be condemned regardless of visual condition.

Inboard engine (if fitted) priority: coastal, liveaboard, motor

Many O'Day 27s carried the Atomic 4 gasoline engine, now well past design life. Check for carburetor condition, raw-water cooling integrity, and overall compression. Repower cost is significant relative to the boat's value — factor this into any offer.

Hull blistering and laminate condition priority: coastal, liveaboard, offshore

Osmotic blistering is common across the production run. Barrier coating without proper drying-out and grinding is a surface fix only. On boats that have been in fresh water or hauled for extended periods blistering may be less severe, but test with a moisture meter at multiple stations.

How it fits your plans

Coastal: A capable and forgiving coastal day and weekend boat in sheltered to semi-exposed conditions. Shallow draft is a genuine asset in the US East Coast, Gulf Coast, and Great Lakes markets. Not suited to sustained offshore passages.
Weekending: Well-matched to weekend use for one or two people. The cabin is compact but functional for short stays. Ease of handling and good visibility from the helm make it a practical choice for occasional sailors.
Liveaboard: Not recommended as a full-time liveaboard. Cabin volume and systems are minimal; headroom and stowage are genuinely limiting. Possible as a temporary or summer liveaboard in a marina but expect significant compromises.
Offshore: Not appropriate for open-ocean passages. Light displacement, limited reserve buoyancy, and modest structural scantlings place this boat outside the offshore category. Coastal and inland use only.
Racing: Competitive within active O'Day 27 one-design fleets where they still exist, but class racing activity has diminished significantly. PHRF racing is possible; the boat is not a competitive club racer against more modern designs.

This guide is the class. A report is that hull. Paste the listing you're looking at and FairKeel grades every claim in it against what's known about the O'Day 27 — where the evidence is thin, the red flags worth a second look, the costs likely to land in your first season, and whether the boat suits the plans you describe in a few short questions.

It won't read the photos or put a number on the boat — that's the $249 Deep-Dive, and for the real answer, a surveyor. It will tell you when a Deep-Dive isn't worth buying. Free, no account, usually a minute or two.

Run a free report on your listing →

See something that doesn't look right? We'd love to know — email us about the O'Day 27 →

Browse all used-boat buyer's guides →