When the engine doesn't start five days before the appointed Panama Canal transit, a lot of things seem to go wrong and happiness goes down the drain. Which is exactly what happened Friday morning. I wanted to start the engine and nothing happened. Click, click, click. No cranking, no stuttering. Just click.
Normally four days should be enough time to sort this kind of problem out. But outside North America and Western Europe marine engine parts are notoriously hard to get. And because on four of the five remaining days shops are closed because of Carnival it's easy to panic.
But feeling panicked is exactly the wrong state of mind for fault-finding or crucial repairs. So instead of throwing myself at the problem immediately I went off to find Greg, the local tinkerer. Every marina has a Greg: Somebody with a knack for mechanical repairs who once sailed there, then got stuck, and is now a permanent installation and busy everyday fixing other people's boats. Which means Greg is notoriously hard to find. So I left a message with his son, asking him to come over to Gudrun when he has some time to help me with the engine.
Then I decided it would be best to ignore the engine problem for a little while and work on something else: filling the fridge cooling circuit with refrigerant.
The new gauges and 134a gas canister were hooked up quickly, but when I looked at the gauges I realized that I had no clue how much gas I should put into the circuit. So I started with "a little" and stopped when the temperature of the evaporator got below zero and then some more. Which turned out to be 8psi on the low side (fridge turned on), and 38psi on the high side (fridge turned off).
With the beer being cooled down I felt slightly more in control of my environment and turned to the engine. After starting at the beginning (electrical connections) and then making sure that the solenoid is ok, the evidence pointed to a faulty start motor. So I removed that from the engine and took it apart. Only to find that it was pretty dirty inside.

Source of the problem: dirty collector on the starter motor
While I was working on it Greg came along. Together we cleaned the starter motor, put it back together, and mounted it on the engine. Turned the key and the engine started. Hurray! From unhappy to very happy in a fraction of a second.
After that Greg checked over the pressure on the refrigerant and declared it to be fine as well. As the sun set I took two cans of cold beer out of the fridge, and zzzzisch, everything was bliss.