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C&C 27 Mk III

Built 1974–1981 by C&C Yachts

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About the C&C 27 Mk III

Researched from public sources for this model. Any individual boat may have been modified or repowered — confirm before relying on any figure.

C&C 27 Mk III
Photo: Ahunt, CC0 via Wikimedia Commons
Built
1974–1981
Builder
C&C Yachts
Designer
Robert Ball
Length
27.86 ft
Waterline
22.86 ft
Beam
9.16 ft
Draft
4.5 ft
Displacement
5,500 lb
Ballast
2,116 lb
Hull
fiberglass
Hull / keel
fin keel
Rig
sloop
Propulsion
inboard
Fuel
20 gal
Water
24 gal
Stern thruster
none
Steering
tiller

The Mark III name was applied retroactively by owners; boats were sold simply as the C&C 27. Hull numbers are given as 451/452-914 by the owners association and 435-915 by sailboatdata. The association says the Mark III came from a new mold with a longer cockpit/stern, deeper keel, less ballast and a taller rig. Wheel steering became a popular option in the mid-1970s (1975 per the association, 1976 (sailboatdata)). Diesel became available in 1978 and a single-cylinder Yanmar (SYP12 (sailboatdata)) was standard by the end of the run; many boats have been repowered. Shoal-draft keel (4.0 ft) was offered. Hull is solid glass (Practical Sailor says the 27 has no hull coring); deck is balsa-cored. External lead ballast through-bolted. The Mark IV (1981-82) and the later, unrelated Mark V (1984-87) are separate versions.

Known problems for this model

1 more
  • Keel shape makes blocking tricky other
    The swept keel has no flat bottom run, so the boat tends to rock forward on jack stands and needs careful blocking when hauled.
    practical-sailor.com

Engines & parts

Universal Atomic 4 parts: good

Factory standard engine — you entered “Universal Atomic 4”

Tens of thousands were built (sources say from 40,000 to 50,000). Despite being out of production for decades, the engine is well supported: Moyer Marine sells parts, rebuilt engines, fuel pump rebuilds and exhaust parts, and hosts an owners' forum; Old Lyme Marina and others also supply parts, and electronic ignition upgrades are available.

Parts sources: Moyer Marine

Common problems (3)
  • Raw-water cooling scale and corrosion cooling
    Most Atomic 4s are raw-water cooled, so the block scales up and corrodes, especially in salt water; cranking without starting can also flood the engine with seawater through the exhaust.
    goodoldboat.com · moyermarineforum.com · keelindex.com
  • Gasoline vapor fire/explosion risk fuel
    Gasoline vapor is heavier than air and settles in the bilge, so ventilation, blower use and shutting the fuel valve (a stuck carburetor float can overflow) matter.
    goodoldboat.com
  • Ignition and fuel system faults electrical
    Points, condenser, cap and wires, plus gummed carburetors and contaminated fuel, are the most common reasons an Atomic 4 won't run well.
    keelindex.com · goodoldboat.com

Sources disagree on first year, last year, number built — left blank rather than guessed.

Model sources (4)

sailboatdata.com · practical-sailor.com · practical-sailor.com · cc27association.com

Other C&C models

Researched from public sources. Spotted an error? The sources are listed above — tell us what they got wrong.