Engineering Mystery Finally Solved (we hope😜)
15 November 2016 | Anchored off Nusa Island near Kavieng, PNG
By Barbara / weather - thunderstorms and rain COOLER!!!
The ship's trusty engineer has patiently struggled with keeping our big alternator going since we bought the boat almost eighteen years ago. Those of you who know us well understand what a big deal this is. Jim has been the most patient human being imaginable as he identified and implemented various apparently partially successful solutions through the years.
The big alternator is an aftermarket installation which we value because it tops off our batteries quickly saving fuel and allowing many boat systems to perform better.
The big alternator problem originally presented with belts breaking during long runs. During our summer in remote British Columbia and Southeast Alaska the local automotive parts shop was invariably our first stop ashore. Captain Jim bought every alternator belt In their stocks that would fit whether pairs were available or not. When another alternator belt failed he patiently and without any naughty language replaced them. He always took special care with the alignment and tension on the dual belts that drive our big alternator to feed our batteries.
Many solutions were tried over the years. He switched from toothed to gates belts. He replaced the pulleys with high quality industrial ones sourced by his brother, Alex who is also a fine engineer. Captain Jim finely sanded and repainted the pulleys to eliminate any fine burrs. He took the alternator itself to professionals for servicing in Fiji and Australia. They found nothing wrong with the alternator.
Our passage from Australia to the Solomon Islands was a bit rough. After arrival Jim discovered that the beefy bolts securing the alternator (and the engine head!!!) had sheared off! He had some spare bolts but not enough. He ordered more from Volvo Penta and did all the prep work so it was a relatively quick install once they reached us in Ghizo.
On passage from Rabaul to Kavieng in Papua New Guinea the big alternator again stopped working. Jim waited until the day after arrival for the engine room to cool down before troubleshooting the problem. He found nothing amiss with the alternator in the engine room except that it was not receiving power.
The next step was to check the connection to the batteries. It was a simple job except that we have been storing extra extra supplies and gear on the aft cabin berth above the batteries. It all had to be shifted elsewhere.
Jim discovered that the small c-clip in the fuse holder that holds the fuse to the alternator had failed! He is convinced that this is the source of the longstanding intermittent problems with the alternator. Underway in rough conditions the fuse would have moved around repeatedly stopping and starting power to the alternator when it was working hard. The hot belts would have been severely stressed starting and stopping abruptly under full load.
Cross your fingers that this will prove to be the end of a serious, longstanding, intermittent and elusive engineering problem aboard Complexity!
Congratulations Captain and Engineer Jim.