Blue View - Nine Reasons to Keep a Maintenance Log

A few years ago, I wrote a blog on the eight reasons to keep a maintenance log on a boat which I have re-posted below. Now that Cups is on the market, I've thought of a ninth reason. As a prospective buyer, I'd be very interested in the maintenance and work that had been performed on the boat during the time the sellers owned it. Perhaps, it's my nerdy, anal engineering background, but keeping track of all the work performed on Cups since we've owned her has been very important to me and now, more than ever, I'm glad I can provide this information to a potential new owner.

BV – 8 Reasons to Keep a Maintenance Log

In my last blog, I listed all the things that broke en route across the Great Australian Bight from Streaky Bay to Esperance. Since then, most of the items have been fixed or put off and added to the lists of to-do's for our stops in Albany or Fremantle. Of course, I've had to start a new list with the next round of repairs and maintenance issues that have occurred since Esperance. Keeping a boat in good fit is a continual challenge, and gets worse once you actually leave the marina.

I keep a maintenance log to keep track of every repair, upgrade and maintenance item done on Nine of Cups. I enter what was done, as well as the place and date, and I find it is a great way to keep track of what was done when. I find that a hardbound laboratory book works perfectly.

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Here are the top 8 reasons I it useful to keep a maintenance log:

  • There are many routine maintenance items that should be done at scheduled intervals: oil changes every 150 hours; finger zincs every 3 months; service the winches; check rigging tension... the list is long. By keeping all the information in one place, I can quickly check to see what is due to be done.
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  • It's a great place to keep notes on the repairs and maintenance that were done. For example, I have a page devoted to sketches of the winch parts and what goes where as it is reassembled after cleaning and greasing the innards. Another page shows the lengths of each lifeline section, so I don't have to remeasure the next time I need to replace them.
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  • It is a good place to record measurements and data. I noted how much shaft vibration I measured after the last engine alignment; battery capacity measurements for each battery before and after the last equalization; wind generator output vs rpms when it was new and when I suspected it was beginning to have problems with brushes; watermaker output in liters/hour when new and after the last time the membrane was replaced.
  • I keep all my maintenance “recipes” in the logbook. How many drops of iroxide yellow needs to be added to white base gelcoat to match the color of our topsides when making repairs to dings and screw holes? How many drops of accelerator do I add to a tablespoon of hypalon adhesive when patching the dinghy?
  • Some parts should be replaced periodically before a failure occurs. A quick look at the maintenance log will remind me how long it has been since I replaced the engine heat exchangers, the shaft seal bellows, or the prop zinc.
  • It's a good way to keep track of how long a part lasted and whether I should be concerned. The cutlass bearing has too much play and was replaced only 3 years ago – maybe I should check the shaft vibration and engine alignment. The primary filter in the diesel line needs replacing after only 400 hours – it may be time to polish the fuel. The prop anode only lasted 3 months – I may have some galvanic corrosion issues.
  • It's a good place to keep vendor/supplier/manufacturer information. We got a good price and a quick delivery on anodes from …; Which suppliers are still around to get parts for our old Ford Lehman engine...; A friend on another boat is looking for a welder in Bahia Caracas, Ecuador – I have an address and phone number in my log book for a good guy we worked with while we were there...
  • And the #1 reason to keep a maintenance log? It's fun to look back at all the exotic places where we did our repairs. We have long lists of things that were done in Capetown, RSA, Piriapolis, Uruguay, Puerto Montt, Chile, and Suwarrow Atoll in the Cook Islands. I also found a list of repairs at Pitcairn Island and even Caleta Martial, a tiny anchorage about 10 nm from Cape Horn where we spent 3 or 4 days waiting out a gale. As I look back through my maintenance log to ascertain when I last changed the engine heat exchangers, I find myself recalling all the fond memories and great friends we met while making all those repairs in so many exotic places.
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