The gyro is often the most expensive single system on a vessel after engines. Most buyers assume it works because it spins. Here's what 150+ assessments taught us about evaluating a gyro before you buy.
Gyros draw power continuously — not intermittently like thrusters. Most vessels we assess have power systems sized for house loads only. Check battery type (AGM vs lithium), bank size, alternator output, and whether a generator is required. Battery sizing guide →
A beautiful paint job on the foundation means nothing. Check for flex, cracking, or movement under load. A loose gyro foundation creates noise, vibration, and premature bearing wear. This is the #1 cause of "my gyro is loud."
Dealers sometimes install smaller units to hit a price point. Verify the model number against the vessel's displacement and beam. An undersized gyro runs at higher RPM, wears faster, and provides marginal stabilization. Load analysis guide →
Sea trials in flat water prove nothing. Ask for a trial in 2-3 foot seas with the vessel at cruising speed. Watch for shutdowns, alarms, or reduced effectiveness. Check how long it runs before the breaker trips or voltage sags.
Ask for all service records. Look for repeated control board replacements, bearing service, or software updates. These are signs of underlying power or structural issues that get band-aided.
The power system is lithium or properly sized AGM, the foundation is structurally sound, the model matches the vessel spec, and service history shows consistent performance. You save installation cost and foundation engineering time.
The vessel is priced accordingly, you want a specific model not originally installed, the existing foundation or power system needs redesign anyway, or you're buying a hull that was never gyro-ready. You control specification, placement, and integration from the start.
The installed unit works but is undersized for your operational profile (e.g., you cruise in rougher seas than the original owner). Budget for power system upgrades, potential model swap, and foundation reinforcement.
A 2022 45' sportfish we assessed had a Seakeeper SK6 installed by the factory. The buyer's sea trial was in 1-foot chop — the gyro performed. After purchase, the owner took the vessel to the Bahamas. In 3-foot seas at cruising speed, the gyro shut down after 22 minutes. The battery bank was AGM, 400Ah total — undersized for continuous 55A draw plus house loads. The alternators were standard 70A units, inadequate for recharge during operation.
The fix: dual 24V lithium bank (800Ah), dual 150A alternators with external regulators, and a dedicated gyro bus. Cost: $18,000. The original "working" gyro was actually a liability.