I recently acquired a 94  21' Chaparral inboard/outboard with the 5.7L Mercruiser and has a Mercruiser lower unit. Boat runs great. We have had it out on the water for a test run, everything works properly. I do not have any service records for this boat. <br /><br />I searched this forum some, but havent had any luck with exactly what I am looking for. I want to know what parts should be serviced, what should be replaced, etc. An example, the impeller. As far as I can tell, it should be replaced every couple of years, and since I dont know when it was last done, I may as well go on and do it. Also, my ujoint bellows is kind of dry rotted. No holes or anything, but it definitely doesnt look new. I am just looking for what parts should be replaced and/or inspected as part of a standard preventative maintenance plan.<br /><br />Thanks for your help!