Took my baot out for the first time in several years and noticed that most of the fluid had leaked out of the compass. The only name I found on it is Mako. My boat is a Mako but I doubt Mako manufactured the compass. There are a set of screws around the top that may give me access to the innerds???? Any one ever been inside one of these? If so what do I refill the compass with? Thanks in advance.