A long time since my last update here!
These past months I have mainly worked, studied and worked - though, alas, not on the boat in question.
However, some small improvements, or shall we say progress, has been made.
As mentioned earlier, I have sealed the gap between the deck and hull with silicone. I have not had the chance to test how good, or bad, this would work before now, simply because all small ponds have been covered with ice! When the ice finally melted, it rained - but a week ago, the weather was fair, and I charged my batteries, and went to the nearest pond to test the boat. Having fitted the batteries, turned on the transmitter and the receivers, I lifted the boat into the water - and just as I did that, I heard the sound of the transmitter telling me it had run out of battery. Argh!
Oh, well, at least the boat still floats...
Yesterday, I tried once again. It rained, but I HAD to test. This time, I made sure I had charged both the lead acid batteries AND the transmitter batteries, before taking the boat down to the pond - and guess what, it worked! I ran the boat for half a minute on near-full power, and then sailed in to shore to chech if there had been any ingress of water. Before sealing with silicone, it would have been lots of water in the boat, but now it was perfectly dry! Success! No use for the pump I installed.
I then proceeded to sail the boat out on the water, but after a few seconds, only one engine would run - and only backwards, at a very, very slow speed. I finally got the boat inshore, and found that the 30 A fuse on the starboard engine (I have mounted a fuse between the motor and the speed controller) had blown. 30 A! I mounted a new fuse, but after a few seconds, this blew as well. I mounted yet another fuse, but after a few seconds, not the fuse, but apparently the speed controller blew! It now refuses to drive the engine anything but backwards.
What a blow: after all, it worked perfectly well before (just look at the videos I have posted), so what on earth has happened now?! I suspect that the starboard engine has a short somewhere - that might explain my earlier trouble with the first set of speed controllers (?). One other thing that I came to think of, is that my engines is held in place with steel bars which is connected to each other: this means that the caps of the engines are connected to each other, electrically speaking: however, I have seen many model boats where this is the case, so should this really be a problem?