Early models of Ficht suffered with sooting of plugs, OMC requested spark plugs should be indexed ie open j end of plug should face the individual injector and the later models were fitted with a small allen head deflector pin recessed beside each plug, this had the effect of spreading the fuel mist and plugs burnt the mixture more efficiently, and didnt soot up, the upgraged models have a visible allen head recessed beside the plug, these models are called Ficht Ram, rather than Ficht, it would be a good idea to have a technician plug into the motor via laptop, suggesting he looks at stored fault codes, max temps, eng hours max rpm, and any stored service logs, and codes.2001 on as far as I know are all the later models, the year is marked on a silverised plate on the cowling below the motor hood where it goes towards the lower unit.Fichts are remarkably fuel efficient, find out if you can locally purchase the recommended xd50 oil, as this must be used, great engines, a 225 and 250 were used on the round Ireland, do a search on
www.boatsetup.com on the motor or hp you are looking at cheers