Friday 10 July Jerujong to Miri

Safely within Jerujong's walls David disassembled and reassembled the couplings between sail drive, gear box and engine looking for a reason for the drive train vibration. There was nothing obvious. We also waited in Jerujong for three days for the winds to abate – our proposed route was taking us straight into them. On day three the wind abated and we were able continue; one night in Kuala Belait river, Brunei and then one more day with wind from the right direction for a good sail to Miri.
Because we had been able to sail most of the way to Miri the engine had seemed better; within half a mile of the marina entrance we turned on the engine to furl sails and line up for the entrance into the marina. Today the wind was onshore and a long swell was running. I put the engine into gear and there was a heart stopping noise and judder from the engine area. I quickly brought the throttle back to neutral and gave David the helm. (If anything's about to go wrong it's his boat.) First he engaged reverse and it was OK. Then forward and the same horrible noise, reverse again OK and then into forward again and OK we had propulsion without the death knell. We manoeuvred into the marina without incident but backing into the slip David couldn't get any forward drive and we smartly collided with rear finger! Fortunately it was a quiet day and I don't think anyone was watching.

one blade off, cleaning the race

detail of an autoprop

Once we were safely moored the questioning began. What's failed?  Gear box, damper plate or sail drive failure? Before disassembling engine again David checked prop shaft from within engine room and could rotate by hand so not seized but still thought it required a visual check from in the water.  Water clarity is poor and there are rumours of crocs but locals assured us it's too noisy in the marina and the crocs prefer to stay up the river. Our intrepid adventurer donned his scuba gear and jumped in to the murk; what he found was one of the propeller blades had seized and not able to move on it's swivel. We have an autoprop which means the blades independently self pitch for the most efficient profile as we travel through the water. Fixed props are less complicated and we carry a spare one under the floor in the forward cabin.

offending bearings sheared in half

So now we had our guilty party and we needed to do was to take prop off, service and refit. Without the option of a haul out we (mostly David) were were going to have to dive and do it in the water.

We dived together, David as the mechanic and brute strength, me as the floating tool box and flash light holder. It wasn't easy and took three hours from start to finish. In order to remove the retaining sleeve nut David had his back braced up against the hull for leverage and I was holding a length of wood jammed between the topside of the fin keel and a blade to stop the propeller revolving. With a big hammer and much straining the nut finally gave and then the precarious removal of the prop from the shaft without losing the nut, key or dropping the prop. At one point we had the prop resting on the wing keel (useful for more than just sailing). Lifting 20kgs 1m up to surface wasn't easy either but from the start David had had the prop secured by rope to the guard rail in case he dropped it.

With the prop on board David took it apart on the dining table to reveal 5 bearings had sheared in half in two of the three blades, the rest of the bearings were dull, pitted and misshapen. Sub standard bearings? We've written to Bruntons to complain as these were fitted just over a year ago. Fortunately we'd kept the bearings taken out then, still shiny and smooth, to replace the year old bearings.  Putting the prop back on was far easier - a mere 30 minutes dive in water where you couldn't see more than an arms' length (or crocodiles watching you).

We tested our handiwork by moving to a different berth within the marina and we're confident this was the nub of our fault.