How should I inspect for rudder damage after hitting a shoal near Mooloolaba?
I think we hit a shoal with the rudder on Grace while coming out of Mooloolaba, and we are now at Rainbow Beach. What should I check for damage, and how can I judge whether she is safe to move?
Answer
Check Grace's rudder-stock entry, steering gear and bilges first: a grounding can damage the stock or its supporting structure without leaving an obvious mark on the blade. Any new stiffness, unusual play, leakage or cracking means keeping the boat secured and arranging a professional inspection before another exposed passage or bar crossing.
Check leaks and steering
With Grace safely secured at Rainbow Beach, open the steering compartment and inspect where the rudder stock enters the hull. Use a torch, inspection mirror and dry kitchen paper to spot fresh water tracks around the rudder tube, seal or gland. Compare bilge levels and watch for continuing ingress.
Keep hands clear of moving quadrants and cables. Isolate the autopilot before inspecting its drive, and stop the engine before anyone enters the water.
- Inspect the structure. Look for fresh cracks, lifted fibreglass tabbing, loose bearing housings and movement where the rudder tube or bearing supports meet the hull.
- Move the steering slowly through its normal travel. Note any tight spot, scraping, clunk or change in effort. Do not force it against resistance.
- Watch the stock and fittings. Check the quadrant or tiller arm, clamp bolts, keys, cables, chain and autopilot attachment for displacement or damage.
- Check for lost motion. Have a helper move the helm gently while you watch whether the stock follows immediately. Slack in the steering linkage and movement in a rudder bearing are different faults.
Photograph anything suspicious before adjusting it. Bolt sizes, tightening torques and acceptable bearing clearances depend on the steering installation. Use the maker's figures rather than tightening everything harder.
Inspect the rudder blade
An underwater camera on a pole gives a useful first look. A diver can inspect more closely when the boat is stationary and conditions are suitable. Neither method reliably rules out a bent stock or damaged internal framework.
- Blade tip and leading edge: look for crushed laminate, missing material, splits and fresh impact marks beneath the antifouling.
- Stock-to-blade junction: look for an opening, cracking or disturbed material where the stock enters the blade.
- Hull clearance: check whether the blade now touches the hull or appears displaced. Clearance can vary through the steering arc, so compare with its previous position where possible.
- Skeg or external fittings: inspect the skeg, lower bearing, heel fitting, pintles and gudgeons where fitted. Impact loads can damage their hull attachments.