B-Atlas Boat Guide · MNSH-34-TR
Mainship 34 Trawler
2005–2009
The Mainship 34 III is the 1983–88 third generation of the original Mainship 34 concept. It keeps the single-diesel, long-keel semi-displacement hull philosophy but uses a more open cockpit, larger salon windows, lighter oak interior and updated exterior styling.
- LOA
- 38′ 10″ / 11.84 m
- LWL
- 34′ 7″ / 10.54 m
- Beam
- 14′ 3″ / 4.34 m
- Draft
- 3′ 4″ / 1.02 m
- Hull behaviour
- Semi-Displacement
- Fuel
- Diesel
- Propulsion
- Shaft
- Engine configuration
- Single Yanmar diesel standard; twin Yanmar diesels optional
- Displacement cruise
- 7 kn · 1.69 US gal/h / 6.40 L/h · 4.14 nm/US gal / 0.91 L/nm
- Faster / planing cruise
- Unknown
- Boat family
- Trawler
- Construction
- Solid fiberglass hull with balsa-cored foredeck
Best for
- Couples cruising inland and coastal waters
- Buyers seeking an affordable classic diesel cruiser
- Owners comfortable updating late-1970s and early-1980s systems
Trade-offs
- Single-screw docking requires technique or assistance
- Balsa-cored foredeck requires careful moisture inspection
- Older fuel, exhaust, electrical and steering systems may require refit
- Single-cabin layout limits guest privacy
Known concerns
- {'ConcernID': 'MNSH-34-MK1-DECK-CORE', 'System': 'Deck structure', 'Description': 'Moisture intrusion in the balsa-cored foredeck is a documented model concern.', 'AffectedYears': {'From': 1978, 'To': 1982}, 'AffectedVariations': [], 'BuyerQuestion': 'Have moisture readings or foredeck core repairs been documented?', 'InspectionAction': 'Moisture-test the foredeck, especially around hardware and the mast step.', 'OwnerAction': 'Maintain bedding around foredeck penetrations and repair leaks promptly.', 'EvidenceRefs': ['https://www.hmy.com/yachting/powerboat-guide/mainship/34-diesel-cruiser-1978-82'], 'Confidence': 'Moderate'}
Inspection focus
- Moisture-test the balsa-cored foredeck around hardware and the mast step
- Inspect aluminum fuel tanks and access for replacement
- Inspect exhaust, cooling, steering, shaft and rudder systems
- Review electrical upgrades and structural alterations
Continue researching
Related boat models
Mainship 350 Trawler
39.75 ft · Semi-Displacement
Mainship 390 Trawler
39.75 ft · Semi-Displacement
Mainship 400 Trawler
41.33 ft · Semi-Displacement
Mainship 34 Diesel Cruiser
34 ft · Semi-Displacement
Mainship 34 II
34 ft · Semi-Displacement
Mainship 34 III
34 ft · Semi-Displacement
About this record
B-Atlas preserves uncertainty: missing information remains unknown rather than being treated as a negative. Specifications and guidance describe the model record; individual boats can differ by year, equipment, refit and condition.