The list below sets out the twenty findings recorded most often in pre-purchase surveys on the Aegean and Mediterranean coast, with their priority classes. It works both ways: a buyer learns what to watch for, a seller sees which items to close before going to market.
Classes: A critical/safety, before going to sea · B short term, this season · C planned maintenance. See the report guide for how to read them.
| Finding | Class | What it means |
|---|---|---|
| Ageing seacocks and hoses | A | The number one source of flooding risk: chalking on bronze, cracked hose and single clamps below the waterline. Double clamps are standard on every hose below the waterline. |
| Weeping shaft seal | A/B | A traditional stuffing box may drip a little; a steady flow is a fault. A dripless seal should not weep at all. Salt traces in the bilge show how long it has been going on. |
| Tired battery bank and charging | B | The first thing to fail on a delivery or at anchor. Corroded terminals, loose posts and a missing main fuse are common. |
| Added circuits in the panel | A/B | Later additions without fuses or in the wrong cable size, wiring outside the colour code. The most frequently corrected item under the ABYC E-11 approach. |
| Aged fuel lines and filters | A | Fuel hose has a service life; hardened hose seeps. On a boat that has stood, water and microbial growth collect at the tank bottom. |
| Elevated hull moisture | B/C | Not osmosis on its own. Drying time, number of readings and the comparison area must be in the report. Widespread high readings can mean saturation beneath the gelcoat. |
| Osmotic blistering | B | Small scattered blisters are common; widespread large blisters are serious. Repair cost must be weighed against the value of the boat. |
| Soft deck laminate | A/B | Found by sounding. Water enters around fastenings at cleats, tracks and winches and wets the core. Early action is cheap; late action means recoring. |
| Leak traces at chainplates | A | The area carrying rig loads on a sailing yacht. Salt staining and early corrosion should never be ignored; a stain on the headlining means opening up and looking. |
| Corroded keel bolts | A | Critical on sailing yachts and gulets. Rust on bolt heads and a crack at the keel-hull joint (the 'keel smile') are structural warnings. |
| Rudder bearing play | B | Excessive play in the stock and wear on the shaft. Checked by working the rudder ashore. |
| Depleted anodes | C | Simple, but neglect damages propeller, shaft and raw-water systems. The rate of depletion also indicates stray current in the berth. |
| Shaft alignment out | B | Vibration, bearing wear and gearbox load. Vibration rising with revolutions on the sea trial is the first sign. |
| Fouled cooling circuit | B | Heat exchanger and raw-water pump impeller. Broken vanes from an old impeller block the exchanger; reduced water at the exhaust is the signal. |
| Aged exhaust hose and waterlock | A/B | Carries water and gas after combustion; a failure can put water into the engine. |
| Bilge pump and float switch failure | A | The system owners trust most and test least. Automatic switches are often stuck or disconnected. |
| Non-compliant gas installation | A | Unvented locker, aged flexible hose, no detector. The quiet item behind fire and explosion risk. |
| Expired liferaft, extinguishers and flares | A/C | Out-of-date safety equipment also creates problems in an insurance claim. |
| Ageing rig and furling gear | B | Wire rigging is generally considered due at 10-12 years. Cracked terminals, stiff furling and UV-tired running rigging. |
| Missing documentation | B | No service records, invoices or previous reports. Undocumented maintenance counts as maintenance not done and lowers value. |
If You Are Selling: Five Items to Close First
- Seacocks and hose clamps, small job, large impression.
- Battery bank and terminal cleaning, the first thing noticed on a trial.
- Bilge cleaning and pump test, salt traces tell a story.
- Safety equipment dates, an expired date reads as neglect.
- Filing the maintenance records, a documented boat sells higher.
If You Are Buying: Walk-Away Signals
- Widespread delamination or a large repaired impact in the hull.
- Cracking at the keel joint or advanced corrosion on keel bolts.
- Extensive wet core in the deck.
- Low compression, or water and metal in the engine oil.
- A seller who will not allow a survey or a haul-out.
What these share is that repair cost can approach the value of the boat. The survey fee earns its keep the day it says "don't buy".
Frequently Asked Questions
Ageing seacocks and hoses. It is the leading source of flooding risk: chalking on bronze fittings, cracked hose and single clamps used below the waterline are the findings recorded most often.
Not on its own. Drying time, the number of readings and the comparison area decide what the figure means. Widespread elevated readings and a single local high spot lead to very different conclusions.
Seacocks and clamps, the battery bank and its connections, bilge cleaning with a pump test, safety equipment dates, and filing the maintenance records. Five low-cost items that change the negotiation.
Widespread delamination, cracking at the keel joint or advanced keel-bolt corrosion, extensive wet deck core, low compression or water and metal in the engine oil, and a seller who refuses a survey.
Wire rigging is generally considered due at ten to twelve years depending on use. Cracked terminals, broken strands and stiff furling are replacement signals, and underwriters also question ageing rigs.
Know the boat before you buy it
Pre-purchase survey ashore and afloat, with photographs, priority classes and cost estimates.
Related Pages
Engine SurveyEngine-related findingsElectrical SurveyWiring-related findingsGas Systems (LPG)Blocked locker drainsGood SeamanshipFindings in preventable formPreparing for a SurveyWhat to close beforehandSelling Your BoatWhat to close before listingSurvey TypesWhich survey do you need?Survey ProcessFrom booking to reportReading a Survey ReportPriority classes and negotiationYacht DeliveryMoving the boat after purchase
Prepared by SurveyYat, ABYC Professional Member, 149 GT Yacht Captain. Last updated: September 2026.
Findings we often see on site
- Osmosis blisters below the waterline: Blisters from pinhead to lentil size under the waterline; some weep an acidic fluid when opened.
- Corroded exhaust elbow: Salt crystals and rust on the outside of the mixing elbow; high elbow temperature on sea trial.
- Overheating electrical connection: On the thermal camera, one pole of the main battery switch is markedly hotter.
- Hairline crack in a rigging terminal: A lengthwise hairline crack at the neck of a lower shroud terminal, seen under the loupe.