The findings we meet most often on surveys. Each card gives what was seen, why it matters and what to do in three sentences, with the instrument used to find it underneath.
Hull
Star cracks in gelcoat
- What was seen
- Hairline cracks radiating from a centre around cleat and winch bases.
- Why it matters
- They mark a point load or an impact; water can get through to the laminate and core beneath.
- What to do
- The area is checked for moisture; if dry, a gelcoat repair, if wet, the structure underneath first.
Found with: 30× loupe
Hull
Osmosis blisters below the waterline
- What was seen
- Blisters from pinhead to lentil size under the waterline; some weep an acidic fluid when opened.
- Why it matters
- They show the laminate is taking on water; repair cost and time grow quickly as it progresses.
- What to do
- A moisture map is taken; depending on extent, drying and an epoxy barrier, or monitoring.
Found with: Tramex Skipper Plus moisture meter
Hull
Opening at the keel-hull joint
- What was seen
- A clear crack and paint separation along the keel joint, at the leading edge.
- Why it matters
- It can point to a grounding or loose keel bolts; the internal structure may be damaged.
- What to do
- Keel bolts and the internal floor structure are inspected; if needed, the keel is dropped and rebedded.
Found with: Phenolic sounding hammer
Hull
Wet core in the transom
- What was seen
- High moisture readings and a dull sound in the transom around the ladder and exhaust outlet.
- Why it matters
- A wet core rots or separates, and the transom carries load.
- What to do
- The wet area is mapped and the entry point sealed; if extensive, the core is replaced.
Found with: Tramex Skipper Plus moisture meter
Deck
Wet core around deck fittings
- What was seen
- Moisture readings rise around winch and track bases; the deck flexes underfoot.
- Why it matters
- Water entering through bolt holes soaks the sandwich core, and the deck loses stiffness over time.
- What to do
- Fittings are removed and rebedded; wet core is cut out and filled or replaced.
Found with: Tramex Skipper Plus moisture meter
Deck
Leaks at portlights and hatches
- What was seen
- Water staining and lifting of the interior lining below the portlights.
- Why it matters
- Leaks damage linings, timber and sometimes wiring; the source is often higher than it looks.
- What to do
- Seals and bedding are renewed; cracked acrylic is replaced.
Found with: Borescope camera
Deck
Teak deck seams and plugs failing
- What was seen
- Teak worn, seams lifting, some plugs gone and screw heads showing.
- Why it matters
- Water gets through screw holes to the deck and core beneath.
- What to do
- Remaining teak thickness is measured; if enough, re-caulking and new plugs, if not, replacement is planned.
Found with: 30× loupe
Engine
Corroded exhaust elbow
- What was seen
- Salt crystals and rust on the outside of the mixing elbow; high elbow temperature on sea trial.
- Why it matters
- The elbow narrows or perforates inside; water can reach the engine or exhaust can leak into the engine room.
- What to do
- The elbow is removed and checked inside; usually it is replaced.
Found with: Infrared thermometer
Engine
Collapsed engine mounts
- What was seen
- Mount rubbers oil-soaked and cracked; the engine sits low on one side.
- Why it matters
- Shaft alignment is lost; the vibration wears the gearbox, gland and bearings.
- What to do
- Mounts are replaced and the shaft realigned.
Found with: Vibration meter
Engine
Salt build-up and leaks in the cooling circuit
- What was seen
- White salt deposits at raw-water pump and heat exchanger joints; drips beneath the pump.
- Why it matters
- As cooling weakens the engine runs hot; the leak also damages the pump shaft and belts.
- What to do
- Pump seal and impeller are renewed, the heat exchanger cleaned and joints re-made.
Found with: Thermal camera
Engine
Hardened, cracked fuel hoses
- What was seen
- Fuel hoses hard with fine cracks on the outside; manufacture date unreadable.
- Why it matters
- A fuel leak is a fire risk and lets air into the engine.
- What to do
- Hoses are replaced with marine fuel hose and proper clamps.
Found with: 30× loupe
Shaft, propeller, rudder
Stern gland taking too much water
- What was seen
- A continuous drip from the stuffing box under way, with rust and salt around it.
- Why it matters
- Water enters the bilge continuously; the packing may be spent or badly adjusted, and the shaft can wear.
- What to do
- The packing is adjusted or renewed; if the shaft is worn, shaft and tube are assessed.
Found with: Borescope camera
Shaft, propeller, rudder
Play in the rudder bearings
- What was seen
- The rudder blade moves sideways when pushed by hand; play is felt in the bearing.
- Why it matters
- As play grows the bearings and stock wear, and control weakens in heavy weather.
- What to do
- Bearing clearance is measured; above the limit, bearings are renewed.
Found with: Laser distance meter
Shaft, propeller, rudder
Propeller cavitation and blade tip damage
- What was seen
- Nicks and bends at the blade tips, spongy erosion on the blade face.
- Why it matters
- Efficiency drops and vibration rises, passing into the shaft and gearbox.
- What to do
- The propeller goes to a specialist for repair and balancing; if erosion is advanced, it is replaced.
Found with: 30× loupe
Electrical
Overheating electrical connection
- What was seen
- On the thermal camera, one pole of the main battery switch is markedly hotter.
- Why it matters
- A loose or corroded connection heats up; it is a common starting point for fires on board.
- What to do
- The connection is taken apart and cleaned, the terminal renewed and torqued correctly.
Found with: Thermal camera
Electrical
Unfused circuit added later
- What was seen
- A circuit added for extra equipment in household cable with terminal blocks, and no fuse.
- Why it matters
- Nothing protects the circuit in a short; household cable fails quickly with vibration and damp.
- What to do
- The circuit is rerun in marine cable, fused and labelled.
Found with: True RMS clamp meter
Electrical
Leakage current on shore power
- What was seen
- A steady current measured on the earth conductor with shore power connected.
- Why it matters
- Leakage is a shock hazard and drives fast corrosion of underwater metals.
- What to do
- The source is traced circuit by circuit; an isolation transformer or galvanic isolator is considered.
Found with: True RMS clamp meter
Corrosion
Spent anodes and low protection
- What was seen
- Saildrive and shaft anodes largely wasted; protection measured with the reference electrode is inadequate.
- Why it matters
- Once anodes are gone, corrosion moves to expensive parts: the saildrive leg, propeller and shaft.
- What to do
- Anodes are renewed, bonding checked and the reading repeated after relaunch.
Found with: Zinc reference electrode
Rig
Hairline crack in a rigging terminal
- What was seen
- A lengthwise hairline crack at the neck of a lower shroud terminal, seen under the loupe.
- Why it matters
- A terminal can fail without warning, and a failed shroud can bring the mast down.
- What to do
- The terminal is replaced, and if needed all wire of the same age.
Found with: 30× loupe
Gas system
Out-of-date gas hose, blocked locker drain
- What was seen
- The gas hose is well past its manufacture date and the gas locker drain is blocked.
- Why it matters
- LPG is heavier than air; if the drain fails, leaked gas collects in the bilge and becomes an explosion risk.
- What to do
- The hose is replaced, the drain cleared and joints checked with a leak-detection solution; a pressure test is done by a qualified gas fitter.
Found with: 30× loupe
Continue with this topic
- Where deck findings start: Keeping the core dry with proper bedding.