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Written by Graham |
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Equipment repairs are one of those fundamentals of cruising life which have about as much appeal to most people as a visit to the local trash dumpster. You may have heard the quip that "Cruising is boat maintenance is exotic places", but what you might not have heard is its corollary that "Maintenance involves sweating in tight spaces". Compared with tales of many of the mechanical and electrical breakdowns suffered by others during the 2002/2003 season in the Bahamas, our experiences have been thankfully less disastrous. The following is a summary of the major challenges we've faced, along with a few thoughts how they might have been prevented. Harken Furler This seemingly simple device is responsible for neatly rolling away our headsail at the end of a trip, as well as reducing its size when the wind blows too hard. Originally installed in 1984 during boat construction, this piece of equipment has stood up exceptionally well to years of (ab)use, but is now showing its age. Two main problems occurred in the past 6 months. Upper Swivel Failure: An upper retaining clip undid itself and allowed all 96 ball-bearings to come cascading down over the decks and into the water. Luckily the repair was fairly simple and consisted of replacing the missing balls and the failed clip. Thank you Harken for shipping us the necessary spare parts so quickly!
Prior warning signs were minimal, except perhaps a slightly elevated level of effort required to roll up the sail. (It was always hard to pull in, so this subtle hint went unnoticed.) Foil Separation: Despite the appearance of a small vertical gap sporadically opening/closing between two upper sections the furler foil, an up-the-mast inspection showed all critical parts apparently still held together by a rigid inner connector and lower roll pin. Due to inherent difficulties working at the top of the mast, nothing further was done to correct what seemed to be a mostly cosmetic problem.. (i.e. "I'd rather be fishing") Naturally the remaining roll-pin fragment fell out at its earliest possibility, and fairly quickly the internal aluminum connector dropped down inside its extrusion. With the upper and lower sections of foil now out of alignment, it became very difficult to lower the sail, and impossible to raise one. Consequently several trips up the mast were required to fabricate a temporary repair, along with several more a week or so later as better judgment dictated we fix it properly. (Retrieving something stuck at the bottom of a 9' aluminum snake waving around 45' above the deck is definitely not my idea of a fun afternoon!) Engine Mount One sunny morning during a motor-sail from Little San Salvador back to the Exuma island chain in the Bahamas, we discovered the fractured head of a bolt sitting in the drip pan under the engine. Obviously since it hadn't been there the day before, it must have just broken off from somewhere, but the big problem was where? Careful inspection with a torch and a "mirror on a stick" eventually showed we were now missing the lower bolt of a series of three on an aft engine mount bracket.
During disassembly, the second (of three) mounting bolts was found to be loose and the bracket slightly bent upward. Most likely the actual bolt failure occurred after a prolonged period running with unfair load distribution.. Inaccessibility played the major role in the repair, as gaining access to the broken bolt required removal of two 4C golf-cart batteries (weighing 60-80lb each) and creative use of tools normally too large to fit in the space available. After straightening and replacing the mounting bracket, the engine needed to be realigned with the propeller shaft in order to ensure smooth running and fair distribution of the load across all four engine mounts. There were few prior indications of anything amiss prior to the failure. Most likely only visual inspection would have led to early detection and prevention of the condition. Such inspections are of course limited by what you can gain access to without major disassembly. Wind Generator Prior to leaving the dock in October 2002 we installed a stern mounted Fourwinds II wind generator to help keep our house batteries charged. Following installation, the unit immediately took top place in the competition for item of equipment requiring most maintenance.
When it works, it works great, but from the very beginning we've experienced persistent vibration severe enough to be felt throughout the boat. In November we returned the blades, wind brake and hub to the manufacturer for rebalancing, but afterwards they shook worse than before. In frustration, we eventually stripped the unit down ourselves, and corrected some rather obvious problems with blade pitch and balance. Upon reinstallation, we were happy to see a significant reduction in vibration as well as a small increase in power output. For the last 3 months, operation has been in line with expectations, even during 35-40kt squalls. Recently the blades even survived an impromptu stress test after tangling with our main halyard. Summary While there have been many individual lessons during these experiences, our overall belief is that:
Crew: Trudy and Graham Norbury, and their cats Sylvester and Shadow
Written 25th April, 2003
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