Hello, I am posting for the first time and I looked but did not find my subject. If I missed it sorry. Here are the facts. 1997 Bayliner 3388, twin 350 s . End of last season ( start of last season replaced both impellers as well as gen set) started getting an alarm sound (like when you first start engines ) it would come and go. We had just lost our life long friend and marine mechanic do an unexpected death ) . First ran a manual check of oil pressure, engines fine. Then checked oil pressure sending unit. Disconnected and alarm stopped. Winterized boat and decided to have at it this year. This year, my son's friend a certified GM (auto) mechanic and electronics whiz) ran another oil pressure check, OK. Tested the oil pressure switch, said it was working. Played with connections, alarm disappeared. Came back a couple of weeks later. It is intermittent . When it comes on, the oil gauge (on bridge ) drops, sometimes(it seems) if you tap gauge, alarm quits. At any rate when ever it quits, oil pressure gauge goes back to normal range. Other than this, engines run fines. Son drives the boat, Last time he was out he said it sounded like "maybe" more than one alarm, was not sure, but again intermittent . Without our dear friend, seeking guidance on where to look and what to check. Any help would be great. The engines have been well maintained and have about 400 hours on them.