converter fan noise

Stick a meter on it and find out, there are AC fans of about any description. Best bet do your yourself a favor and change it over to a Progressive Dynamics. I have yet to hear the fan in ours.

Not sure but I think the old Magnatek fans are AC vs DC based - if so the std computer fan won't work. In my case I found cleaning/oiling was only temporary solution.

Never found a bearing yet that I couldn't get some oil in, even if it means drilling a hole. Question is, is it worth the trouble ? And trouble is, every time I've done it, it was short lived.
If its wore out its probably an old single stage ?? Deep six it !

You might try cleaning the fan blades and lubricating the fan bearing. I've had more than one fan recovered by doing this and the cost is low.

Not without removing the old. Go for it. Worst case get a new converter.

My guess is, "Yes." They are very much like the fans in computer power supplies. You would just have to disconnect both shore and battery power, pull the cover off the converter, get the specs off the fan, and see if you can find a replacement. If you have to order one, you would have to put everything back together and put up with the noise until the new one arrives.

Rob