I have a 3 year old 310 with a universial. There has always been a rattle when high rpms were reached, but since it is a sailboat, we never kept in up there too long. This year however, I decided to investigate. After much crawling around in the aft berth and more than a few phone calls, it was suggested to me to have the engine aligned. The stated tolerance, I was told between the flange plates is 0.004". Can anyone validate this? If not I'll post after I have aligned the engine. (I'm just waiting until a good 90+ day to do the work......not)