We’ve had a pretty subdued start to the season. The weather hasn’t been great in Scotland and yet we’ve watched, listened to, and read forecasts of hot sunny days further south in the UK. The fact that winter hasn’t fully retreated yet, arguably makes our ‘current‘ technical problem slightly easier to swallow. During one of the half-decent weekends that we had recently, we intended to head out for our shake-down sail. Unfortunately just before we were about to set-off our plans were scuppered when our Malin’s engine wouldn’t start.
Our Macwester’s Lombardini diesel engine is a reasonably recent replacement engine with low hours so we reasoned that a problem with the starter motor was unlikely. After a few simple diagnostics we were reasonably sure that the batteries were flat, so we took them home and I gave them a good charge. Both batteries appeared to maintain a healthy charge over several days. I was a tad confused as to why there should be a problem with either of the batteries, and given that I had nagging concerns about the Osculati main isolator switch (above, left switch), I bought an identical replacement and swapped these over. With the timely help of a passing friend, we managed to get the batteries back on board our yacht. I should perhaps mention that as the batteries are both half a metre long, I can’t tell you how happy I was to bump into the passing friend I mentioned, as I really hadn’t worked out how we were going to get the batteries from a bobbing dinghy back on to our Macwester Malin. Before long I had both fully charged batteries reconnected.
Unfortunately the engine still wouldn’t start. By this stage, we knew for sure that this was a battery problem as we had started the engine in the interim period with a car battery. Deciding to try to start the engine with one single battery, I persevered and after trying three combinations of the 2 x leads to 2 x battery terminals I got the engine started on the fourth and last combination. We decided to head to Capernaum where we would get easy pontoon access to fix the problem …whatever it was.
The short journey was completed without any problems, although the wind was gaining in strength and we were taken sideways as we entered the harbour. Of course we couldn’t rely on the bow thruster because of the battery problem, nonetheless we managed to get on to the pontoon easily given that there were friends ashore to take the ropes.
On Sunday the 5th of May the wind changed direction and with the tide well in, by midnight we were getting a bit of a bashing from a south-easterly (from the direction of 11 o’clock in the photo above), which was bring waves right into the harbour and pushing us against the pontoon. I got up and sat on watch for half an hour. Our Malin’s bow and stern were swinging up and down by anything up to 0.75 of a metre at times, but the centre of the yacht was relatively still and I reasoned that there was no danger that our new navy blue Majoni fenders were going to ride up over the pontoon as they’re 0.7m tall. Eventually I went back down into the aft cabin and managed to nod off despite the fairground ride and sound of the waves slapping firmly into our Mac’s hull.
The following day, while I was scratching my head and taking advice on the battery problem, I took advantage of being on the pontoon to do some smaller jobs. This included swapping out an old stanchion block, which was a bit sticky when we were operating the head sail, with a new Holt 450 block. Hopefully we’ll notice the difference when we eventually get out for our shake-down sail. At the same time, ‘the crew’ re-did some whipping on our new fenders, as she wasn’t happy with the first attempt.
With the help of a friend from the club, we discovered that one of the batteries dropped from over 12v to about 4v under load. The old battery didn’t go without a fight; later we discovered that it had chewed through my jeans and my hoody as I wrestled it off to the recycling centre. Our friend kindly sourced a replacement Yuasa Cargo battery with 143 Ah the following day and he even managed to swing a better deal than the £190 retail price for us [yay!]. With that, our Macwester Malin was fully operational once more. However we still had a small problem of some sort, as there was a spark when the leads were connected up to the batteries even although the isolator switch was off. This meant that there was something constantly drawing power from the batteries.
I reasoned that this problem was likely to be something that had been happening since we bought our Macwester 32 early in 2011, and that we had been able to sail throughout two seasons despite it. Nonetheless I decided that it made sense to keep going and try to identify the problem, rather than just live with it and assuming that everything would be okay as it had been previously.
This post is already overly-long so I’ll finish up now. As things stand, we’re fully operational. According to another friend (and electrician), it might be the bow thruster that is the source of the spark, or more accurately perhaps a sticky relay that sits between the batteries and the bow thruster. We’re still running diagnostic checks, however one solution might be to introduce a new standalone isolator switch for the bow thruster. We’ll keep going and we’ll find a solution over the coming week or two. The good news is that at this stage it looks as though there’s nothing that will stop us from going out for our shakedown sail come the next suitable day that we have free.