C&C 35 Mk III

Built ?–1987 by C&C Yachts

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About the C&C 35 Mk III

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

Illustration of a C&C 35 Mk III — **Illustration, not a photo of this model.** AI-generated illustration of a typical mid-size cruising sloop.

Built: ?–1987
Builder: C&C Yachts
Designer: Robert Ball
Length: 34.67 ft
Waterline: 28 ft
Beam: 11.17 ft
Draft: 6.08 ft
Displacement: 10,825 lb
Ballast: 4,500 lb
Hull: fiberglass-cored
Hull / keel: fin keel
Rig: sloop
Propulsion: inboard
Fuel: 20 gal
Water: 30 gal
Stern thruster: not fitted

Tank capacities — where the figures come from

Fuel 20 gal
“Fuel Capacity 20 gal” — search excerpt (1987), rcryachts.com · “20 gallons of fuel” — search excerpt (1983), boattrader.com

Two listings agree; no builder figure found.
Water 30 gal
“30 gallons of water” — search excerpt (1983), boattrader.com · “Water Capacity 32 gal” — search excerpt (1987), rcryachts.com

Listings give 30 and 32 gal; an owner's report of 80 isn't used, so 30 rests on listings alone. C&C was a Canadian builder, so the gallon unit is uncertain.
Holding unknown
“24 (catalog value)” — spec database, sailboatdata.com · “a 20-gallon holding tank” — search excerpt (1983), boattrader.com · “Holding Capacity 12 gal” — search excerpt (1987), rcryachts.com

Sources give three figures: 24 gal from a spec database, and 20 and 12 from listings. Holding tanks are often owner-fitted on boats of this age, and no builder figure was found.
Water heater unknown
No builder document, review or listing found that states the C&C 35 Mk III water heater.

Tanks are often replaced or added on older boats — check the tank labels or a survey for yours.

Thrusters and steering — where this comes from

Bow thruster unknown
No source mentions a thruster on the C&C 35 Mk III.
Stern thruster not fitted
Nothing was found either way; our earlier figure of none appears to be an assumption.
Steering unknown
No builder document, review or Edson data sheet found states the steering system of the 35 Mk III (1982-87).

Thrusters and steering are often replaced — check the units on your boat before ordering parts.

Sources disagree on first year, holding tank — left blank rather than guessed.

All-new design that replaced the earlier C&C 35. Start year disputed (1982 vs 1983); built through 1987. Keel/centerboard version: 4.16 ft up / 6.4 ft down, 12,150 lb displacement, 5,700 lb ballast. Hull coring: owners describe it as a cored boat and Practical Sailor says C&C's 35-foot and larger boats of the period have balsa-cored hulls. Holding 24 gal is owner-reported. Engine hp (27) from a broker listing. Engine access is tight. Tender for its rig; better suited to coastal cruising and club racing than offshore.

Engines fitted

Yanmar 3GM30F — diesel, single standard
Wikipedia (citing sailboatdata and Sailing Joy specs): the 1982-87 Mark III is fitted with a Yanmar 3GM30F diesel, 20 gal fuel. Earlier Mk I/II boats used the Atomic 4 gas engine (Westerbeke diesel a later Mk II option). Rating not stated for this boat in the source read.

Sources: en.wikipedia.org

Generator

No source mentions a generator for the C&C 35 Mk III.

Known problems for this model

Keel smile and keel sump damage hull
The keel-hull joint can crack (the C&C smile) and hard-raced or grounded boats have needed keel sump rebuilds; owners say US-built boats had more keel-area problems than Niagara-built ones.
sailnet.com · forums.sailinganarchy.com
Stiff but brittle in groundings hull
An owner reported cracked stringers and keel-joint damage after groundings, and the designer is quoted as saying the stiffer build suffers more in a hard strike than earlier boats.
forums.sailinganarchy.com
Rod rigging and aluminum chainplates rigging
Rod rigging needs periodic re-heading or replacement, and the aluminum chainplates can corrode against stainless turnbuckles after many years.
sailnet.com · forums.sailinganarchy.com
Leaking long cabin windows deck
The long cabin windows commonly need resealing.
sailnet.com
Core moisture at deck penetrations deck
Moisture-check the cored deck around fittings, chainplates and the cockpit sole; owners say the factory left core out around original through-hulls.
sailnet.com · forums.sailinganarchy.com

2 more

Mast step rigging
Owners advise inspecting the mast step; one keel bolt sits under the mast, so keel work requires unstepping.
sailnet.com · forums.sailinganarchy.com
Holding tank leak and shallow bilge plumbing
One owner found a leak at the top of the holding tank; the shallow bilge (especially on keel/CB boats) lets water spread, and a dripless shaft seal is suggested.
sailnet.com · forums.sailinganarchy.com

Engines & parts

Yanmar 3GM / 3GM30F parts: good

Factory standard engine — you entered “Yanmar 3GM30F”

Very popular (used 3GM30Fs sell for $3,000+) and supported by a strong parts network. Cylinder head overhauls (valve seals, lapping, injector service) are a common, parts-supported repair.

Parts sources: Mack Boring & Parts (Yanmar distributor), HDI Marine (stainless exhaust elbows), Parts4Engines

Common problems (2)

Overheating at cruise rpm cooling
The 3GM30F has a known overheating tendency linked to its heat exchanger; owners also trace it to coked elbows, worn impellers, scaled heat exchangers or air in the raw water circuit. Some heat exchangers were replaced under warranty.
forums.sailboatowners.com
Mixing elbow corrosion exhaust
OEM elbows corrode internally and should be inspected or replaced with stainless versions before they let water into the engine.
practical-sailor.com · facebook.com

Maker’s service schedule (2)

Fuel filters & water separator	250 hrs	“The normal replacement interval for the element is 250 hours ... Filter cleaning First time 50 hours Filter element repl” — manufacturer, c320.org
Air filter / intake silencer	250 hrs	“Washing period Every 250 hours” — manufacturer, c320.org

Service part numbers (10)

Oil filter	Yanmar 119305-35170 Replaces 119305-35151, 119660-35150	“3GM30F Basic Service Kit ... 119305-35170 1 FILTER ASSY, D68XL65” — dealer, oldportmarine.com · “Maintenance kit Yanmar 2GMF, 2GM20F, 3GMF, 3GM30F ... Yanmar 119305-35170 Oil Filter” — dealer, marinedustrie.com
Fuel filter	Yanmar 104500-55710	“Fuel Filter Element 1 104500-55710 / Fuel Filter O-Ring 1 24341-000440” — dealer, ellebogen.com · “3GM30F Basic Service Kit ... 104500-55710 1 ELEMENT, FUEL FILTER” — dealer, oldportmarine.com
Raw-water impeller Japan-built 3GM / 3GM30(F) (serial not starting with E)	Yanmar 124223-42092	“Impeller 1 124223-42092 / Impeller Gasket 1 124223-42110” — dealer, ellebogen.com · “3GM30F Basic Service Kit ... 124223-42092 1 IMPELLER, PUMP” — dealer, oldportmarine.com
Raw-water impeller European-built GM-YEU (serial starting with E)	Yanmar 128990-42570 Replaces 128990-42200	“(Supersedes part number: 128990-42200) ... 3GM30-YEU, 3GM30C-YEU 3GM30F-YEU, 3GM30FC-YEU” — dealer, palmerpower.com · “It fits Yanmar 2GM20F, 2YM15, 3GM30F, 3GM30FC, 3TN30F, 3YM20, 3YM30, 3YM30AE engines. Cross Reference: 128990-42200” — dealer, deltadieselparts.com
Drive belt	Yanmar 25132-003700	“Alternator Belt 1 25132-003700” — dealer, ellebogen.com · “3GM30F Basic Service Kit ... 25132-003700 1 V-BELT, A37” — dealer, oldportmarine.com
Drive belt	Yanmar 104511-78780	“S/W Pump Belt 1 104511-78780” — dealer, ellebogen.com · “3GM30F Basic Service Kit ... 104511-78780 1 V-BELT, M/19” — dealer, oldportmarine.com
Air filter	Yanmar 128270-12540	“Air Filter Element 1 128270-12540” — dealer, ellebogen.com · “3GM30F Basic Service Kit ... 128270-12540 1 ELEMENT, AIR CLEANER” — dealer, oldportmarine.com
Zinc / anode raw-water 3GM / 3GM30; also sold for the F (heat-exchanger) versions	Yanmar 27210-200300	“27210-200300 Yanmar Engine Zinc Anode For 2GM(D), 3GM(D), 2GM20, 3GM30” — dealer, zincsforboats.com · “It fits Yanmar 2GM, 2GM20F, 2GM15, 2GM20, 3GM30F, 3GMF, 3HMF, 3GM30H engines.” — dealer, deltadieselparts.com
Thermostat 3GM30F / 3GMF (fresh-water cooled)	Yanmar 121750-49800	“Thermostat 1 121750-49800 / Thermostat Gasket 1 129350-49541” — dealer, ellebogen.com · “Thermostat for Yanmar 2GMF, 3GMF, 3HMF, 2GM20F, 3GM30F, 3HM35F / REC121750-49800” — dealer, marineparts.eu
Thermostat 3GM / 3GM30 (raw-water cooled)	Yanmar 105582-49200	“Replaces Yanmar Marine 105582-49200 ... 1GM, 2GM, 3GM, 1GM10, 2GM20, 3GM30” — dealer, repowermarine.com · “1GM10, 2GM20 & 3GM30 Thermostat to fit raw water cooled engine versions ... equivalent to 105582-49200” — dealer, parts4engines.com

From the engine maker’s parts lists, or two independent parts dealers. Numbers change with serial number and get superseded — check yours before ordering.

Model sources (10)

sailboatdata.com · sailnet.com · forums.sailinganarchy.com · practical-sailor.com · goodoldboat.com · willismarine.com · sailboatlistings.com · spinsheet.com · listingsport.com · en.wikipedia.org

Other C&C models

C&C 27 Mk III 1974–1981
C&C 30 Mk I 1973–1985
C&C 33 Mk II 1984–1988
C&C 34 1977–?

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