Im hoping Elvin (or anybody) can answer two questions. I have a 2002 Nissan NSF18BEF1 that has as estimated 300 hours of running time. How soon should the camshaft drive belt be replaced? Also, is this an interference engine (piston to valve contact)? I use my boat on lakes in very remote areas and sometimes dont see anybody else on the water for several days. Im considering keeping a spare belt on hand but if I break one and this is an interference engine Id probably be out of luck anyway.<br /><br />Thanks in advance,<br />Bruce