October 1, 2006
Sandy
Bay--El Bight
Isla de Guanaja, Honduras, CA
16º 27.313 North
85º 52.161 West
Bits and Pieces
By Douglas Bernon
We have a friend, a successful sailboat racer, who admits that
in his youth he would try and confound his opponents by any means,
fair or foul. When passing another boat or being passed, he would
sometimes throw rusty cotter pins or half-sheered bolts up against
their main sail, so that when they fell to the deck, either the
sudden sound or the later discovery would unnerve his adversaries.
I can see why. I hate finding broken bits anywhere. Every morning
when Bernadette and I are on passage, I make a full and leisurely
tour of our deck, looking up and down, examining this and that and
hoping, always, to find potential problems before they surprise
us.
Ithaka has extraordinary access all around the engine. Three
sides come away and the fourth is accessible from below. |
I also check the engine every day we’re under way. Granted
it’s a cursory look. I don’t study every inch, but I
look for wet, salty or oily evidence of something that might be
leaking, loose, oozing, or just not right. I listen to the engine.
I smell it. I take a basic temperature with my hand. I check the
oil and the belts and the level of anti-freeze in the overflow tank.
What I don’t always do, though, is reach under the engine
into the small bilge and feel for evidence of something having gone
haywire and tucked itself into an inconvenient, unpleasant cranny.
Or at least I didn’t used to.
In Isla Providencia, after Mr. Bing and I determined the easy-to-mend
difficulty with our water pump, I was utterly surprised to discover
shreds of black rubber in the bilge under the engine. At first I
checked the belts to see if one had thrown off a bit, but the pieces
I found were too thick to have come from any of the belts. I checked
the hoses; all were intact. Then, as I examined the pieces of shredded
rubber collected in my hand, it dawned on me where they had to have
originated.
Ithaka has an ingenious engine arrangement.
Coming off the front of the engine (the opposite end from the
shaft leading to the propeller), there’s another small shaft
(sometimes called a power take-off) that extends forward, and
ends up being hidden under the settee in the main salon. Belted
to this shaft are two devices: the high-output alternator dedicated
to our house bank of batteries, and the belts from the refrigeration
compressor.
Anyone who has aligned an engine knows that
it takes time and patience. After all, one measures not with a
yardstick, but with a set of feeler gauges that are merely 1/1,000ths
of an inch thick. With this kind of precision, when the faceplates
meet, if they’re
the tiniest bit out of whack, they may as well be WAY outta whack.
Add to this inevitable and minute disparity that there is yet another
axel of sorts on the front end, and it’s clear why it’s
impossible to perfectly align everything. To compensate, many engines
have a flexible coupling between the two plates; this is an incredibly
strong, highly forgiving, rubber “doughnut” that, when
secured around the two rotating devices, allows them to spin together
with a minimum amount of vibration. When I grow up, I aspire to
be more like them: tolerant of imperfection.
Seen from above, the power take off is on the right hand
side of the photo. The flexible coupling cannot be seen
from this angle but is almost directly below the blue hose.
The right hand area is usually covered by settee cushions. |
Turns out, it was our flexible coupling that was the source of
the rubber shards at the bottom of Ithaka’s engine
pan. Imagine a 6-inch-diameter baby-carriage tire with a three-inch
center opening. Now imagine that this tire is slit open so that
it can slip over the two turning parts, then be bolted to both parts
-- thus absorbing the slight wobbles of the two rotating together.
Think radial tire now, laced with embedded fibers, that give it
its extraordinary strength.
On Ithaka, this inexpensive coupling
is pretty useful, and although we have many thousands of dollars
worth of spare parts—injectors,
starters, alternators, and watermaker heads—I’d never
thought to get us a spare for it. And on Isla Providencia, the only
hardware store was fresh out. Without the power-take-off doing its
job, it would take us nigh on forever to charge our batteries from
the smaller engine-mounted alternator dedicated to the start battery.
End of the world? No. Damn inconvenient? With several remote anchorages
and an offshore passage to the United States ahead of us? You bet.
The ever-shredding coupling was gradually disintegrating.
It is the original one used in the boat so it lasted for
fourteen years. Pretty darn good for a $13.00 part that
was stressed constantly. |
Providencia has an internet café that’s open several
hours a day. Bernadette spent some time in there Googling “flexible
couplings” and were able to locate a company in America who
makes our particular kind of coupling, called a Fenaflex. They said
they could ship one to our next destination, Guanaja, so we ordered
the part and had it shipped to our friends Jack and Elizabeth at
Lighthouse.
Between Providencia and Guanaja is a three-day
sail. But we also wanted to stop in at the Vivorillos, a remote
bank off the coast of Nicaragua. We decided to cobble together
our own temporary repair, figuring it wouldn’t make anything worse; that it would work
as long as it worked; and that when it stopped working we could
high tail it to Guanaja. However, when Bernadette I asked each other
how we might best go about effecting this jury rig, nothing leaped
to mind – that is until I asked myself what would David on Zia
Lucia, or Cade on Sand Dollar, or Frank on Simba do?
They’re the most creative fixers I know, and I’ve often
thought they could make anything out of chicken wire and bubble
gum.
Thinking that very expression opened up the
door for me. If those were such fine ingredients for repair work,
what were the equivalent goodies I had squireled away on board?
The answer seemed to be fiberglass matt, Interlux’s two-part epoxy and 3M’s 5200 spooge.
I sliced up thin strips of fiberglass matt, then cut it further
and teased it apart so that there were small pieces and individual
strands as well. I saturated them thoroughly with the two-part epoxy
and painted the mixture into the inside of the tire where light
was showing through. I used the same material to cover the holes
on the outside as well. By lacing it on both sides of the coupling,
I hoped to create a stable web onto which I could lay the 5200,
but I didn’t want to use too much matt or epoxy; the goal
was to keep things supple. Anything rigid might prove too brittle
-- sort of like people.
Inside the little tire you can see an orange area, which is where
the saturated matt is flat. |
I cut up more itty-bitty shreds and mixed them directly into a
mound of 5200 already squirted out of the tube, figuring that it
might give some radial strength. Then, on the outside of the tire
where there were major chunks missing that had spun off like a bad
retread on the highway, I worked in the mix, and we let it cure
for 72 hours before putting it back on the engine and giving it
a test ride. A week probably would have been better, but we were
growing impatient to move on.
For so many things on board, 5200 is the magic fix. It’s strong, waterproof, flexible and easy to work with. On land people often default to duct tape. On board, this is often the first thought. |
Once everything was reassembled and the doughnut was back in place,
we fired up the engine at low RPM to see if the little tire would
hold together, and not peal into piecemeal orbit. We increased revs
until we were full throttle, and still the little bugger held together.
We used it steadily to charge our batteries for the remainder of
our time in Providencia as well as in the Vivorillos.
By the time we got to Guanaja, some ten days and twenty-plus hours
of motoring after installation, there was still structural integrity.
Despite the high torque of the engine, the repaired coupling had
not shredded completely, although its demise was clearly foreseeable.
I was again picking bits from the bilge. In Guanaja we received
the new Fenaflex (and a spare as well). I took off our homegrown
version and cinched down its replacement.
New and Repaired Flexible Coupling |
Looking back, this was a pretty successful
short-term fix, but now I know I would’ve done it differently. Instead of using
the two-part epoxy (which really is not made for this application
but did its job with gusto) and fiberglass matt, I would’ve
cut some strips of dinghy patch and used the two-part rubber glue
to fashion the support layers. Then, once I had the holes covered,
I’d lay in more layers over that with a good bit of fiberglass
matt as well as the glue. I could have achieved, I think, a more
durable construction. But the real moral of the story is not about
spooge or matt or engines or glue. It’s this: If life is going
to work on board a boat, or anywhere else, a flexible coupling is
required.
The
entrance to Guanaja from seaward. |
The very best vulcanizing agent (glue
for rubber and hypalon) is a German industrial product
that’s often used to hold manufacturing conveyor
belts together. We’ve used it for long-term and
incredibly strong repairs on dinghy rips. I’ve
never seen it at stores in the States, but it can be
ordered from a variety of sources on the Internet: Rema
TipTop SC 2000 is really good stuff.
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