I have a BD1005 engine with a high output alternator installed two years ago. After raising the sail (noisy, windy conditions) I pressed the kill button and turned off the key. Unfortunately I didn't press long enough and the engine was still running when I turned off the key. Did I blow the diode? How can I test. If blown, how do I fix.
This is one of those questions that I can't answer. You need to run the engine and see how the system charges. If it is charging ok, assume that all is ok and leave it alone. Just dont make the same mistake again.
If the system is not charging the way it should, you need to take the alternator off the engine (be careful and switch off your batteries. Do not cause any sparks) and take the alternator to an alternator repair shop and ask them to repair the alternator. Although we keep all spare parts in stock here, most alternator shops will have the parts in stock as well.