O'DAY 31
Specifications
Hull
| LOA | 30.12 ft |
| LWL | 25.58 ft |
| Beam | 10.75 ft |
| Draft | 5.25 ft |
| Displacement | 10,100 lb |
| Ballast | 3,799.6 lb |
| Hull speed1.34·√LWL | 6.8 kn |
Rig & Sails
| Iforetriangle height | 39.75 ft |
| Jforetriangle base | 13.25 ft |
| Pmainsail luff | 33.75 ft |
| Emainsail foot | 10.25 ft |
| FLforestay | 13.3 ft |
| Mainsail | 450.1 sq ft |
| Jib (100%) | 263.3 sq ft |
| Spinnaker | 447.7 sq ft |
Engine
| Universal | M-1818 hpSee all 11 parts → |
About the O'DAY 31
Updated/extended version of O'DAY 30/RANGER 30. (1977?) Available with shoal draft keel. draft: 3.92 ft; displacement: 10,400 lbs.; ballast: 4,100 lbs
Designed by C. Raymond Hunt Associates and built by O'Day Corp. (USA) from 1985–1988, the O'Day 31 is a robust coastal cruiser with a production run of 150 hulls. Its heavy displacement of 10100.0 lb and fin keel configuration provide a stable, comfortable platform, though owners frequently report structural maintenance needs in the keel sump and deck core.
- Best for:
- This boat suits coastal cruisers and weekend sailors who prioritize comfort and stability over high-speed performance, particularly those willing to undertake significant DIY maintenance on the deck and keel structure.
- Bluewater capability:
- With a capsize ratio of 1.99 and a comfort ratio of 24.5, the O'Day 31 is capable of offshore passages, but its bluewater readiness is heavily contingent on addressing critical structural issues like keel sump cracking and deck core moisture before attempting extended voyages.
- Comparables:
- Comparable boats include the Cal 30 and Hunter 30, which share similar beam dimensions and masthead sloop rigs, but the O'Day 31 distinguishes itself with a heavier displacement and a more traditional, solid build quality typical of the mid-1980s O'Day line.
Performance
Estimated Value
Low ConfidenceAsking price by model year
6 listings · boat years 1985–1986 · median $18,500
Each dot is one listing · hover for details · dashed red line marks the median · obvious data-entry outliers (top & bottom 2.5%) excluded.
Estimated Cost of Ownership
Based on 30.12ft LOA. Actual costs vary by condition, usage, and local rates.
Known Issues & Pre-Purchase Inspection
24 reported issues across 9 systems for the O'DAY 31, compiled from owner reports in sailing forums and owner-association material.
Unlock the full inspection report
Thinking of buying a O'DAY 31? This is an in-depth report on the faults this model is known for — so you know exactly what to check when you walk the boat. For the price of a coffee.
- ✓ All 24 specific issues — severity, symptoms & fixes
- ✓ Model-specific pre-purchase inspection checklist
- ✓ Downloadable PDF to take to your surveyor — yours to keep
One-time $2.99 · secure checkout by Stripe · instant access · 30 days online, PDF yours to keep
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Engine Parts & Maintenance
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Used sails that fit the O'DAY 31
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