LEAKS ARE BAD
So, I took off yesterday for my birthday. I decided that the boat was going back into the water that day, since I would be
off. I have replaced a couple of thru-hull connections and added a ground plane plate, each of which required putting new
holes into the boat or removing old parts and replacing them with new. Since it was possible that one or more of these
three points had not sealed correctly, I wanted to be there when the boat went into the water, just to be sure. Also, I
wanted to do this on a weekday, so that I could get the boat back out of the water, any problem fixed and back into the
water the next day. If I tried to put the boat in on a Saturday, and it leaked, I would not be able to get it back in until the
following Saturday – unless, of course, I took an “emergency” day off.
By 11:00, they had the boat lifted into the Travel-Lift and positioned next to the water. I put the last bits of bottom paint on
and by 3:30, the boat was finally ready to lower into the water. Once the boat got into the water, but before it was
completely floating, one of the yard guys hopped on board to check for leakage. The good news was that the three spots
that I was worried about were all bone dry. The bad part was that I had a leak in the front end of the boat.
One of the pieces of gear I had replaced early in the yard period was the transducer of the depth sounder. The transducer
that I had when we pulled the boat out of the water worked fine, but I had gotten a “good deal” on a digital module at a
used boat parts store. This module allowed the signal from the transducer to be sent directly to the Multi-Function Display
at the helm station. This would allow me to have a view of the bottom on the screen, rather than just having a digital read
out of the depth. In some previous boats, I had a “fish finder” that would provide a similar function, but I never really used
it. The only two pieces of depth information that really concern me is “how deep is the water where I am” and “is that
deeper or shallower than it was a moment ago.”
Did I mention it was a good deal? This piece of equipment is usually $500, but I got it for just under $400. Obviously, I
had to have it.
So, I am all set up to install the new digital sounder, but it turns out that the connector from the old transducer does not
connect to the new digital module. I will need to replace the transducer itself. Suddenly, the “good deal” I got on the digital
module is not such a good deal, when I factor in the cost of a new transducer. But, do I simply say, well, then I won’t install
the module? OF COURSE NOT! That would be a waste of $400, leaving out the possibility that I could just resell the darn
So, I take out the old transducer and look at it. Because of the thickness of my hull and the angle of the hull, the shaft on
the old transducer was very long. Looking at replacement transducers, the long shaft replacements were very expensive –
a minimum of $500. However, an “inside the hull” transducer was significantly less expensive. So I ordered one of these
The inside the hull transducer was about the size of a hockey puck and took about a week to arrive. As soon as I got it, I
realized it wasn’t going to work. In order to get a good reading the transducer face has to be pointed straight down. This
particular transducer had an adjustable housing that allowed it to be installed as much as 22 degrees off of the horizontal
plane. However, the only places in my hull that did not require the transducer to try to shoot thru a foot or more of the
fiberglass hull had angles greater than 30 degrees from the horizontal. I could have built up a floor that would get to 22
degrees, but only by adding at least 5 inches of fiberglass to the inside of the boat. Back the “inside the hull” transducer
went and I bit the bullet, ordering a long shaft transducer.
Since I had to order a long shaft anyway, I ordered one that included a little wheel arrangement that would read boat
speed through the water as well. Because of this, the transducer came with a “high speed fairing” that attached to the
exterior of the hull and protected the transducer. The idea was that you measured the angle of the hull and then, using a
band saw, cut the fairing at the appropriate angle to match it. The, you glued the fairing to the hull and installed the
transducer in it. I immediately ran into two problems. First, I had no band saw and second (and this was the bigger
problem), the spot where I needed to put the transducer was at too great an angle. If I cut the fairing at that angle, I would
no longer have the fairing.
No problem, thought I. I will simply build a piece to go between the fairing and the hull that is tall enough to get the
appropriate angle. First, I cut polyethylene “boards” to about the correct size, then I drilled an appropriate size hole in
each, so that the transducer shaft would fit through them. Then, I wrapped the shaft in wax paper and made a plastic block
by using epoxy to glue the boards together in a stack until it had the right dimensions. The transducer shaft was used to
keep the boards in alignment while it set up. Next, I removed the transducer and, using a table saw, I cut the block to the
correct angle. I coated the entire thing with more epoxy and let it cure.
After the block was good and solid, I took the transducer, the block and the fairing to the boat. The new transducer shaft fit
through the same hole as the old transducer, so I took off the old bottom paint in the area where the block would go. Then,
using some more thickened epoxy and the transducer shaft again wrapped in wax paper, I attached the block to the hull,
holding it in place with the transducer and the fairing block. I let that set up for a week or so.
After I was sure that the block was attached good and solid, I removed the transducer shaft and put marine sealant
between the fairing and the block, gooping it in good and thick. I gooped the area around the fairing/block connection and
the area where the block attached to the hull, just in case the epoxy had not covered the entire area. I gooped everything
good and tight, and slid the transducer up in place to hold it all while the goop set.
Now, here’s where the problem occurred. I did NOT seal the transducer in place. I don’t remember why I didn’t. I am sure
that I had a good reason not to. I just don’t remember what I was. I know that I knew – at the time – that I would have to
come back and pull the transducer one more time, in order to seal it in place. But I didn’t.
Later, I remember tightening down the nut that holds the whole assembly in place good and tight and I remember putting
the little spinning wheel assembly in place and tightening that up. So, by the time we actually went to put the boat into the
water, I had forgotten all about the fact that I had never sealed the transducer in place.
The yard guy knew that I had replaced the transducer, but he couldn’t remember exactly where the location was. I hopped
on board the boat and pulled up the deck plate over the location. The bilge there was full of water. Luckily, the transducer
sat in its own little bilge pocket, so we only had a couple of gallons of water in the boat and the boat had only been
lowered to the point where the bilge pocket was just full. But, we needed to pump it out and see what the problem was.
First we hooked up a pump and started pumping out the water, but it would only go down a little bit because as soon as
we pumped out water, more water came in from the transducer shaft. Next we raised the boat a foot or two out of the
water, which allowed us to pump all the water out, but now we couldn’t tell where the leak was, because the leak was no
longer under water. So we lowered the boat back into the water and that’s when we realized that the transducer shaft was
We first tried to just remove the nut at the top of the shaft and reseal it, but this didn’t even slow the flow down. They lifted
the boat back out of the water and moved it over land, where we all gathered around the fairing and block and everyone –
we had a crowd by this point – could see that there was no sealant around the transducer itself.
OK, no problem. We’ll just pull the transducer out, seal it real good and pop it back into place. Let the sealant dry and we’
d be ready to go back into the water.
The transducer wouldn’t come out. Apparently, there is just enough sealant around the shaft from where I sealed the
fairing to the block that it was holding the transducer in place, but not enough to actually seal it. With two guys hanging
onto the bottom and one guy pushing from the top, the transducer would come down about half an inch, but as soon as
one person let go, it slid right back up into place.
At this point, I bowed to the inevitable and told the yard guys that I was turning the problem over to them. I needed to get
home to get cleaned up, because we were going out to dinner with friends and this problem was going to take a couple
hours of diligent effort to solve. The area had to dry out before they could add any more sealant anyway, so we dropped
the boat back down onto some blocks and, when I left, they were using very long, thin knives to try to cut around the shaft
without damaging it.
So, hopefully, today they will get the transducer resealed and the boat back into the water. When I get home tonight, I will
be ready – I hope – to take the boat to the new slip and start working on getting it all put back together.