I own a 1992 Chaparral 1800SL limited with a 3.0L mercruiser stern drive. Recently I believe it blew the exhaust gasket. It is not overheating, no water in the oil and it does not idle poorly. In fact it seemed to run just fine except for the hissing noise. I could see where the exhaust gases were leaking from and I have not run it since. <br /><br />I would like to know how difficult it would be for me to change this gasket and what parts and tools I would need. For starters I do have the factory shop manual for this year engine. But all other advice would be appreciated.<br /> <br />Thank you for your time