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BRUNTONSAustralia

The diagnostic suite

Something's wrong. Start with the symptom.

Boats broadcast exactly what ails them — the skill is decoding it. Pick what your boat is doing and get the cause tree, the free checks to run first, and the honest fix. At least a third of these answers end in 'don't buy a propeller'.

10 symptoms mappedfree checks firsthonest outcomes
Engine won't reach max RPMOver-pitched or oversized propeller — most likelyDiagnose →
Black smoke under loadOver-propped engine lugging below rated RPM — most likelyDiagnose →
Vibration at cruising revsDynamic shaft misalignment — most likelyDiagnose →
Noisy aft cabin under powerPressure pulses from tight tip clearance — most likelyDiagnose →
Prop keeps spinning under sailHydraulic gearbox that can't self-lock — most likelyDiagnose →
Weak or wandering reverseBlades that present a poor face astern — most likelyDiagnose →
Slower than sistershipsFixed-blade drag under sail — most likelyDiagnose →
Overheats when pushedOver-propped engine at sustained high load — commonDiagnose →
Anodes fizzing or vanishingStray current at the berth — most likelyDiagnose →
Clunk or shudder into gearWorn flexible coupling or engine mounts — most likelyDiagnose →

Symptom not listed, or several at once?

Describe it to an engineer — a video of the shaft at idle answers more than a form ever will.

Talk to the workshop

Diagnosis pointing at the propeller?

The Builder takes your symptoms into account — it screens for exactly these problems before recommending anything.

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