[Uhehner]

RO30009 is a platinum plug for Crusader 8.1 engines. Somewhere I read that they had a 1000 hour rating, much like the 100,000 mile plugs in new cars. When I thought I had an engine miss I contacted Jerry's Marine (Crusader distributer 1-800-432-2231) in FTL and they supplied Denso/TJ14R-P15 plugs. Turned out to be the crankshaft position sensor and covered by a recall. My engines came with AC41-993 plugs when new. Capt. George