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Don't Ignore Them; Small Leaks Equal Big Problems


This is the first of a monthly blog I am writing for By way of introduction I would like to tell you a little bit about myself before I get down to my first topic, "Small Leaks, Big Problems."

Almost forty years ago I decided to take the summer off between college and law school and do some sailing. I took a job as a deck hand on a ketch based in New York and we sailed Downeast. While in Maine I had the opportunity to meet the builder of that boat, and to see his shop. What I saw tugged at my heartstrings in a way that changed the course of my life.

The ketch was Rosa II and the builder Paul Luke. With a one year extension of my law school admission, I went to work for Paul, earning $ 3 an hour. Daily I pondered the choice before me: law school or boatbuilding. On tough days when I couldn’t do anything right and Paul or Earle Dodge would let me know it, my buddies would ask me if I was having a “law school day.”

But the allure of lofting and set up, joinery and spar making, and launching and sea trials won out, hands down. To paraphrase Frost, “two roads diverged in a dusty boat shed and I--I took the one less travelled by, and that has made all the difference.” A huge chunk of my life will be linked forever to the ROSA and to Paul Luke.

From Lester Rosenblatt, Rosa’s owner, I learned the importance of detail, and the disproportionate effort required to climb from 90 percent to 95 percent. From Paul Luke I learned about hard work, the virtues of self- reliance, and the drive to get the job done, not to mention the skills of boatbuilding.

A summer job became a career and a lifestyle, and I’ve always marveled at the impact ROSA II and Paul Luke have had on my life. I started my own boatyard 32 years ago and have been fully immersed in boatbuilding and repair ever since.

I have had the good fortune to cruise from Nova Scotia to the Bahamas, and from Anacortes to Alaska, and have made the trip from Virginia to New York under sail over forty times. Yet somehow I still like a beginner with so much more to learn.

This combination of immersion in the business and craft of boat repair, combined with the cruising adventures gives me a unique perspective on boating matters, and this blog will approach topics from that vantage point. I enjoy seeing the forest and the trees and often wonder why we always describe that view as choice between one or the other. Please feel free to email your suggestions, questions, or feedback. Write me at


It is amazing how much damage can be done by a small leak neglected for a long time. I am old enough to have lived aboard a boat with a traditional planked deck. Every spring we went through the ritual of marking leaks, and then hunting them down. It has been said that a recession is when your neighbor loses his job, and a depression is when you lose yours. As for leaks, it was certainly true that a minor leak was when it dripped onto the crew’s berth, and a major leak was when it dripped onto the owner’s. Thankfully boat construction has evolved, but even on modern composite boats, leaks remain important and should not be ignored.

Perhaps it is an occasional trickle from a window or porthole. The teak cabin side changes color so gradually that you no longer notice it. Eventually the stained veneer becomes objectionable, but at that point it is too late for simple refinishing. At best the veneer must be cut out and a new piece fitted and glued. Getting this new piece of wood to look like the ten year old wood around it can be exceptionally difficult.


The same can be said of a small weep or drop coming from the raw water pump or heat exchanger on your engine. The loss of water may be inconsequential, but the damage insidious. Little by little the engine mount beneath is begins to rust. The threads freeze up making adjustments into an ordeal. Or perhaps the transmission housing slowly peels its paint as rust bubbles up from beneath. Have you ever tried to sand and paint and irregular shape like a transmission?


A similar situation occurs with older teak decks. Perforated with hundreds of screws and many yards of seam comp

ound, a teak deck laid over a cored fiberglass deck has many opportunities for leaks. Perhapsthere is an occasional stain on the headliner in the forward cabin (which is rarely occupied). That small leak may well result from a deck seam leaking water under the deck and then running down one of those screws and finding its way into the core. By the time you attend to the problem you might find a foredeck in need of rebuilding due to core deterioration.

Foredecks are particularly notorious, due to so much hardware and so many penetrations. Windlass foot switches seem to be a common culprit and after all, these leaks happen in the chain locker, where no one looks and no one cares. But the mold and mildew and general dampness are not good, and if the moisture is working its way into the deck core, the problem can become severe.

I recently inspected a boat and found that the foot switches had been installed on a balsa core deck, without protected the core from moisture. I could feel the wet cardboard quality of the immediately surrounding core, and half of the foredeck pegged my meter. The seller accused me of misleading the buyer by testing the deck on a rainy day. I didn’t notice the rain from the cramped space I had crawled into under the deck.

teak deck thin plugs

Some leaks are good, like the one on a conventional shaft stuffing box. A certain drip rate is appropriate and needed to properly cool the gland. If the drip rate increases, most people respond by tightening the gland, a reasonable response. But if it keeps leaking and you keep tightening, you will likely score the shaft, wearing away more mils than is acceptable. In many such cases the shaft must be replaced, substituting a several thousand dollar shaft for a shaft repacking of a far lesser amount.

So here’s my advice. Think of that leak as a messenger, each drip calling to you for attention. The leak might not be a problem for you, but the damage it is causing will likely turn out to be far more expensive than correcting the leak.

Started in 1981, Zimmerman Marine specializes in all aspects of boat service, including “everything from minor repairs to major refits.” Zimmerman Marine has service facilities in Maryland, Virginia and North Carolina. The company also builds semi-custom cruising boats and offers its own line of downeast-style cruisers.