Bertram 31 Flybridge Cruiser
Built 1961–1983 by Bertram Yacht
About the Bertram 31 Flybridge Cruiser
Researched from public sources for this model. Any individual boat may have been modified or repowered — confirm before relying on any figure.
- Built
- 1961–1983
- Builder
- Bertram Yacht
- Length
- 30.58 ft
- Beam
- 11.17 ft
- Draft
- 3.08 ft
- Displacement
- 10,600 lb
- Hull / keel
- planing
- Propulsion
- inboard
- Fuel
- 222 gal
- Water
- 18 gal
- Holding
- 12 gal
- Bow thruster
- none
- Stern thruster
- none
The original production deep-V; over 2,000 31s of all versions built (hulls_built covers all versions, not just Flybridge Cruisers). Regular production ended 1983, plus a 1986 Silver Anniversary run (HMY says 23, BoatUS 20). Fuel 170 or 222 gal. The 31 Sport Fisherman is the same boat without the cabin bulkhead. Build count (approximate, not stored): HMY: over two thousand 31s of all versions built.
Known problems for this model
-
Fuel tank replacement fuel
Many 31s have had original tanks replaced; owners stress that aluminum replacements fail early from trapped bilge water, abrasion and rubber-on-aluminum contact unless coated, properly supported and kept clear of standing water.bertram31.com
-
Wet ride hull
The classic deep-V is an exceptional rough-water boat but a wet ride.hmy.com
Engines & parts
MerCruiser 5.0 (305) / 5.7 (350) V8 gas parts: good
Factory standard engine — you entered “MerCruiser gas V8 inboard”
GM small-block Chevrolet base engines, so internal parts are everywhere. Marine exhaust manifolds and risers for 1983–2002 small blocks are sold by many aftermarket makers (Sierra, Barr, Osco and others) through Power Boat Supply, Hardin Marine, Basic Power Industries and similar stores; Mercury sells genuine parts through dealers.
Parts sources: Power Boat Supply, Hardin Marine, Basic Power Industries
Common problems (2)
-
Manifold/riser failure and water in cylinders exhaust
Cast-iron manifolds and risers rust internally or their gaskets fail, letting water back into the cylinders; small amounts cause hard starting and rough running, large amounts hydrolock and wreck the engine. Service roughly every 7 years in fresh water and about 5 in salt.powerandmotoryacht.com · forums.iboats.com · justanswer.com
-
Overheating from scaled manifolds cooling
Rust and scale inside the manifolds restrict cooling flow and cause overheating under load.powerandmotoryacht.com
Model sources (2)
Other Bertram models
- Bertram 28 Flybridge Cruiser 1971–1994
- Bertram 33 Flybridge Cruiser 1977–1992
- Bertram 35 Convertible 1970–1986
Researched from public sources. Spotted an error? The sources are listed above — tell us what they got wrong.