Month: October 2023

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Engine Harness Repaired

The engine ignition switch was working intermediately. The problem was traced to a plug in the engine harness, which when pushed together allowed the ignition system to work. The two plugs in the harness were taken apart with some difficulty due to corrosion. Note the plug on the right is the one that was working intermediately, and the reason is evident as one of the pins was broken.

The plugs were soaked for 30 minutes in white vinegar, neutralized by a solution of baking soda, the cleaned and dried with CRC Marine QD Electronics Cleaner.

The plugs were filled with Permatex Dielectric Grease, plugged and unplugged several times to spread the grease, then the harness was reassembled and the plugs were wrapped with electrical tape. Note the bypass for the broken pin.

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Engine Room Light Converted to LED

There was a classic explosion-proof light in the engine room. It was originally equipped with an incandescent lamp. As was done for the other lights in the boat, I wanted to convert the lamp to LED. My first effort was to use LED replacement lamps that have the usual Edison screw base, but I found the LED lights were unreliable and after a sail or two they would stop working. Looking for something more robust, I came upon these strings of LED lights that could be cut to any length.

I pulled the guts out of the old light. Then string of LEDs has an adhesive back, so mounting them was easy. I am very satisfied with the final result. The light is now much brighter than it was originally.

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Simrad Fluid Level Sensor Installed and Main Fuel Tank Calibrated

The specs for an Alajuela 38 claim a fuel capacity of 75 gallon. However, after emptying the tank into jerry cans, I measured the capacity to be 60 gallons. While measuring the capacity, I also calibrated a Simrad Fluid Level Sensor model 000-11518-001. The process involved adding ten gallons at a time and measuring the resistivity of the sending unit:

Volume (Gallons)Resistivity (Ohms)
0255
10193
20127
3098
4070
5051
6042

Note the change in resistivity is not linear. This is due in part to the non-linear behavior of the sending unit, but mostly due to the V-shape of the fuel tank. Without calibration, a “half tank” according to the mechanical gauge was probably in fact about a quarter tank. Having used five points to calibrate the Fluid Sensor (Empty, 1/4, 1/2, 3/4, and Full), it presumably gives a more accurate measurement of the fuel volume (highlighted in red).

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Asymmetry Spinnaker Repaired

I bought a used asymmetric spinnaker for $300, about 10% of what a new one costs. A large rip in the sail had been repaired with sail tape, but I decided to replace the ripped panel. I started by cutting out the panel along the seam.

I removed the residue from the tape using this 3M product … it worked perfectly.

I then used the cut out panel as a template to mark the new fabric with chalk. One of the straight edges of the new 1.5 oz nylon fabric was attached to one of the edges of the sail using double-sided basting tape, then the other side was attached with basting tape using the chalk outline as a guide. The panel was sewn on using a zig-zag stitch with UV-resistant polyester V-69 thread and a Sailrite Ultrafeed LSZ machine (on the table in the background).

Once a single set of stitches were applied, the extra material was cut away and a second set of stitches were applies. A few other holes were also patched.

While the sail is not perfect, I will use it to decided if an asymmetric spinnaker is my preferred downwind solution. If it is, I will order another spinnaker and keep this one as a backup.