Day 112 – BRM Dead

Where Next?
Bob Williams
Mon 4 Apr 2022 09:05
Noon Position: 33 49.6 S 079 36.9 E
Course: NNE Speed: 4 knots
Wind: NW F3 Sea: slight
Swell: SW 1m
Weather: mostly sunny, mild
Day’s Run: 120nm

We continued our pleasant sailing, close reaching under full sail to the predominantly gentle NW breeze. This forenoon the winds have been light so I thought it a good opportunity to have another look at the engine and see whether I could perhaps get it started; however, the news is not good.
I got the engine prepped, opening the exhaust valve and sea cock and turning on the engine battery, checked the oil – full and clean, and the coolant – full. Then I thought I would try to start it using a technique that the Ineffable had suggested, namely cranking the engine over with one’s hand over the inlet manifold for about 30 seconds then taking one’s hand off and seeing whether it fired. The theory goes that blocking off the inlet manifold while turning the engine over lowers the pressure on the inlet side causing the inlet valves to remain open, thereby reducing the compression and the amount of work the starter motor is doing – sort of like proxy decompression levers. This allows plenty of fuel to get into the cylinders and increases the compression when one’s hand is taken off the inlet manifold thereby increasing the probability of the engine starting.
To this end, I removed the air cleaner and was concerned to see a bead of water sitting in the orifice of the inlet manifold. I got a torch and had a closer look inside the manifold and to my dismay saw more water further inside. I tried barring the engine over with a large socket on the crankshaft nut but the shaft would not budge. I next took the rocker cover off to see what I could see there – nothing untoward though signs of previous oil contamination. Then I pulled off the inlet manifold which was a bit more of a chore but allowed me to see into the inlets for each of the cylinders. Not a pretty sight, lots of water and some obvious corrosion. There was clearly water in the cylinders. Next I took the sea water hose off the exhaust mixing elbow and was greeted with a column of water rising up out of the elbow. It would seem that despite having the exhaust valve closed, sea water had still managed to make its way past the valve and into the engine. I next pulled the exhaust hose off the mixing elbow and a torrent of water poured out of the hose and into the bilge.
This is of course all very disappointing. I can only assume the exhaust isolation valve has failed despite being dismantled and fully serviced during the New Zealand refit. I have now cleaned the engine up as best I can, sprayed some WD40 into the inlets of each of the cylinders and closed the engine box up. I have a strong suspicion that the engine is likely to be a write off. Certainly I can’t see myself being able to repair it out here. Probably the best thing I can do from here is pull the head off and clean the water out of the cylinders to prevent any further corrosion, and clean the head and valve gear likewise, then preserve the engine until I can get to port and have it fixed, if fixed it can be. But taking the head off is a big job. I feel I need to regroup a little before starting on it. Maybe tomorrow.
In the meantime we continue to sail in the gentle breeze.
All is well.