I have a 1988 Bayliner Capri with I/O 5.0L 305 OMC out drive. This is my first ever boat and I have spent a lot of time rebuilding this boat. Out of all the problems I had, I only have a few left. This includes the oil temp and water temp gauges not working. They read nothing when the boat is running. I have no idea as to what the problem is as I'm new to boats and motors. I have been told it could be a bad gauge, bad sensor/sender, bad oil pump. I have no idea where to start to diagnose these issues. Any help is greatly appreciated. Thank you for your time