• Slide: The Image of 1973 Bertram 31 Flybridge Cruiser helm with steering wheel and navigation instruments. - 1The Image of 1973 Bertram 31 Flybridge Cruiser helm with steering wheel and navigation instruments. - 1
  • Slide: The Image of 1973 Bertram 31 Flybridge Cruiser engine compartment with dual Yanmar engines. - 2The Image of 1973 Bertram 31 Flybridge Cruiser engine compartment with dual Yanmar engines. - 2
  • Slide: The Image of 1973 Bertram 31 Flybridge Cruiser deck, featuring spacious layout and clean design. - 3The Image of 1973 Bertram 31 Flybridge Cruiser deck, featuring spacious layout and clean design. - 3
  • Slide: The Image of 1973 Bertram 31 Flybridge Cruiser interior with striped seating and table, docked at marina. - 4The Image of 1973 Bertram 31 Flybridge Cruiser interior with striped seating and table, docked at marina. - 4
  • Slide: The Image of Interior of a 1973 Bertram 31 Flybridge Cruiser with striped seating and table. - 5The Image of Interior of a 1973 Bertram 31 Flybridge Cruiser with striped seating and table. - 5
  • Slide: The Image of Interior of 1973 Bertram 31 Flybridge Cruiser bathroom with sink and toilet. - 6The Image of Interior of 1973 Bertram 31 Flybridge Cruiser bathroom with sink and toilet. - 6
  • Slide: The Image of 1973 Bertram 31 Flybridge Cruiser interior with sink, storage, and window view of marina. - 7The Image of 1973 Bertram 31 Flybridge Cruiser interior with sink, storage, and window view of marina. - 7
  • Slide: The Image of 1973 Bertram 31 Flybridge Cruiser cabin with striped cushions and wooden interior. - 8The Image of 1973 Bertram 31 Flybridge Cruiser cabin with striped cushions and wooden interior. - 8
  • Slide: The Image of 1973 Bertram 31 Flybridge Cruiser navigating open waters at sunset. - 9The Image of 1973 Bertram 31 Flybridge Cruiser navigating open waters at sunset. - 9
  • Slide: The Image of Aerial view of 1973 Bertram 31 Flybridge Cruiser speeding on open water. - 10The Image of Aerial view of 1973 Bertram 31 Flybridge Cruiser speeding on open water. - 10
  • Slide: The Image of 1973 Bertram 31 Flybridge Cruiser speeding on open water at sunset. - 11The Image of 1973 Bertram 31 Flybridge Cruiser speeding on open water at sunset. - 11
  • Slide: The Image of 1973 Bertram 31 Flybridge Cruiser navigating ocean waters at sunset. - 12The Image of 1973 Bertram 31 Flybridge Cruiser navigating ocean waters at sunset. - 12
  • Slide: The Image of 1973 Bertram 31 Flybridge Cruiser sailing on open sea with distant mountains. - 13The Image of 1973 Bertram 31 Flybridge Cruiser sailing on open sea with distant mountains. - 13
  • Slide: The Image of 1973 Bertram 31 Flybridge Cruiser navigating open sea under clear blue sky. - 14The Image of 1973 Bertram 31 Flybridge Cruiser navigating open sea under clear blue sky. - 14
  • Slide: The Image of 1973 Bertram 31 Flybridge Cruiser on scenic lake with forested hills. - 15The Image of 1973 Bertram 31 Flybridge Cruiser on scenic lake with forested hills. - 15
  • Slide: The Image of A 1973 Bertram 31 Flybridge Cruiser speeds across a vast blue ocean under a clear sky. - 16The Image of A 1973 Bertram 31 Flybridge Cruiser speeds across a vast blue ocean under a clear sky. - 16
  • Slide: The Image of 1973 Bertram 31 Flybridge Cruiser on calm water, American flag, clear sky. - 17The Image of 1973 Bertram 31 Flybridge Cruiser on calm water, American flag, clear sky. - 17
  • Slide: The Image of 1973 Bertram 31 Flybridge Cruiser on calm water, clear sky background. - 18The Image of 1973 Bertram 31 Flybridge Cruiser on calm water, clear sky background. - 18
  • Slide: The Image of 1973 Bertram 31 Flybridge Cruiser on calm water, displaying classic design. - 19The Image of 1973 Bertram 31 Flybridge Cruiser on calm water, displaying classic design. - 19
  • Slide: The Image of 1973 Bertram 31 Flybridge Cruiser on calm water, featuring classic design and American flag. - 20The Image of 1973 Bertram 31 Flybridge Cruiser on calm water, featuring classic design and American flag. - 20
  • Slide: The Image of 1973 Bertram 31 Flybridge Cruiser on calm water, featuring "Happy Mama" nameplate. - 21The Image of 1973 Bertram 31 Flybridge Cruiser on calm water, featuring "Happy Mama" nameplate. - 21
  • Slide: The Image of 1973 Bertram 31 Flybridge Cruiser "Happy Mama" on calm waters, Portsmouth, NH. - 22The Image of 1973 Bertram 31 Flybridge Cruiser "Happy Mama" on calm waters, Portsmouth, NH. - 22
  • Slide: The Image of 1973 Bertram 31 Flybridge Cruiser "Happy Mama" on calm waters, Portsmouth, NH. - 23The Image of 1973 Bertram 31 Flybridge Cruiser "Happy Mama" on calm waters, Portsmouth, NH. - 23
  • Slide: The Image of 1973 Bertram 31 Flybridge Cruiser "Happy Mama" in Portsmouth harbor, clear sky, American flag. - 24The Image of 1973 Bertram 31 Flybridge Cruiser "Happy Mama" in Portsmouth harbor, clear sky, American flag. - 24
  • Slide: The Image of 1973 Bertram 31 Flybridge Cruiser "Happy Mama" in Portsmouth harbor with American flag. - 25The Image of 1973 Bertram 31 Flybridge Cruiser "Happy Mama" in Portsmouth harbor with American flag. - 25
  • Slide: The Image of 1973 Bertram 31 Flybridge Cruiser "Happy Mama" on water, Portsmouth, NH. - 26The Image of 1973 Bertram 31 Flybridge Cruiser "Happy Mama" on water, Portsmouth, NH. - 26
  • Slide: The Image of 1973 Bertram 31 Flybridge Cruiser on calm water, with American flag, sunny day. - 27The Image of 1973 Bertram 31 Flybridge Cruiser on calm water, with American flag, sunny day. - 27
  • Slide: The Image of Close-up of RPM gauges on a 1973 Bertram 31 Flybridge Cruiser. - 28The Image of Close-up of RPM gauges on a 1973 Bertram 31 Flybridge Cruiser. - 28
  • Slide: The Image of Engine compartment of a 1973 Bertram 31 Flybridge Cruiser, featuring a Yanmar engine. - 29The Image of Engine compartment of a 1973 Bertram 31 Flybridge Cruiser, featuring a Yanmar engine. - 29
  • Slide: The Image of Engine of a 1973 Bertram 31 Flybridge Cruiser, featuring a Yanmar diesel engine. - 30The Image of Engine of a 1973 Bertram 31 Flybridge Cruiser, featuring a Yanmar diesel engine. - 30
  • Slide: The Image of 1973 Bertram 31 Flybridge Cruiser control panel with switches and marine safety notice. - 31The Image of 1973 Bertram 31 Flybridge Cruiser control panel with switches and marine safety notice. - 31
  • Slide: The Image of 1973 Bertram 31 Flybridge Cruiser deck with American flag and wooden step. - 32The Image of 1973 Bertram 31 Flybridge Cruiser deck with American flag and wooden step. - 32
  • Slide: The Image of 1973 Bertram 31 Flybridge Cruiser bow view at marina, calm water reflections. - 33The Image of 1973 Bertram 31 Flybridge Cruiser bow view at marina, calm water reflections. - 33
1/34

1973 Bertram 31 Flybridge Cruiser

$117,900

Used

Boat in Portsmouth, NH 03801 US

builtBuilt in 1973
Year the boat was built
model

31 Flybridge Cruiser

Boat model
engine

2 Engines (2x Yanmar)

Engine type and count
length

31 feet

Overall boat length
fuel

Diesel

Fuel type
material

Fiberglass/Reinforced

Hull material
1973 Bertram 31 Sportfish Cruiser - Happy Mama

Location: Portsmouth, NH
Type: Flybridge Sportfish
Hull Material: Solid Fiberglass
Fuel Type: Diesel
Engines: Twin Yanmar 6LPA-STP 315hp
Engine Hours: ~1,500

OVERVIEW

Repowered in 2004 with twin 315hp Yanmar 6LPA-STP diesels, Happy Mama is a clean and mechanically updated example of the legendary Bertram 31.

This is a fantastic cruising platform or serious offshore fishing vessel. Designed by C. Raymond Hunt, the Bertram 31's solid fiberglass deep-V hull and contemporary lines were far ahead of their time and remain highly respected today.

Major engine interval service was completed in 2023, making her turnkey and ready for her next owner.

She retains her original interior and gelcoat, preserving the classic Bertram character, while numerous upgrades ensure reliable performance.

PERFORMANCE

  • Cruise: 24-26 knots @ 3,000-3,200 RPM

  • Approx. 18 GPH at cruise

  • Top Speed: ~30 knots WOT

  • Legendary rough-water capability and dry ride

2024 UPGRADES

  • Brand new 1½" propeller shafts

  • New cutlass bearings

  • Line cutters installed on shafts

2023 SERVICE & IMPROVEMENTS

  • Major Yanmar interval service:

    • Aftercoolers removed, cleaned, painted & reinstalled

    • Heat exchangers serviced

    • Oil, fuel & transmission coolers serviced

    • All new hoses and clamps

  • New PSS dripless shaft seals

  • (4) reinforced swivel rod holders

  • Livewell pump added

ADDITIONAL UPGRADES

  • Fusion stereo system (2022)

  • Reconditioned props (2021)

  • New rudder bearings (2021)

  • EZ2CY bridge enclosure (2020)

  • Garmin 18xHD Radar (2018)

  • Garmin 7610sv MFD (2017)

  • New batteries (2018)

  • Custom SEAmless hardtop (2017)

ACCOMMODATIONS

  • Forward V-berth

  • Convertible dinette

  • Galley with sink and refrigeration

  • Enclosed head

  • Classic Bertram teak trim

THE BERTRAM 31 PEDIGREE

Few production hulls have earned the reputation of the Bertram 31. Offshore proven, heavily built, and timeless in profile, it remains one of the most sought-after classic sportfishing platforms ever produced.

Happy Mama is a well-maintained example offering updated diesel power, strong service history, and the ride that made the 31 famous.

Nominal Length
31ft
Length Overall
31ft
Beam
11.17ft
Drive Up Draft
3ft
Dry Weight
11000lb
Cruising Speed
24kn
Max Speed
30kn
Hull Material
fiberglass
Hull Shape
deep-vee
Engine 1
Engine Make
Yanmar
Engine Model
6LPA-STP
Total Power
315hp
Engine Hours
1500
Engine Type
inboard
Fuel Type
diesel
Engine Year
2004
Drive Type
direct
Engine 2
Engine Make
Yanmar
Engine Model
6LPA-STP
Total Power
315hp
Engine Hours
1500
Engine Type
inboard
Fuel Type
diesel
Engine Year
2004
Drive Type
direct
Disclaimer

The Company offers the details of this vessel in good faith but cannot guarantee or warrant the accuracy of this information nor warrant the condition of the vessel. A buyer should instruct his agents, or his surveyors, to investigate such details as the buyer desires validated. This vessel is offered subject to prior sale, price change, or withdrawal without notice.

Price History

DateEventPrice
2/20/26Initial price$117,900

Contact Bay Marine - Ohio

1535 1st Street, Sandusky, OH, 44870

By checking this box, I consent to receive recurring marketing text messages, phone calls, and emails from Bay Marine - Ohio at the number and email provided, including messages sent using an autodialer or prerecorded voice. Message frequency varies. Message and data rates may apply. Reply STOP to opt out or HELP for assistance. Consent is not a condition of purchase. We'll also send helpful email updates about your boat search. You can unsubscribe whenever you like. See Terms of Use and Privacy Policy.

Be the first to know when similar boats hit the market

Get notified when new boats become available

Meet the Broker

Address

1535 1st Street
Sandusky, OH 44870

Boat Location

Be the First to Know

Get notified when new boats become available.

Contact Bay Marine - Ohio

1535 1st Street, Sandusky, OH, 44870

By checking this box, I consent to receive recurring marketing text messages, phone calls, and emails from Bay Marine - Ohio at the number and email provided, including messages sent using an autodialer or prerecorded voice. Message frequency varies. Message and data rates may apply. Reply STOP to opt out or HELP for assistance. Consent is not a condition of purchase. We'll also send helpful email updates about your boat search. You can unsubscribe whenever you like. See Terms of Use and Privacy Policy.

or