He is now in the 4,500 range on his Lehman and says that 10-15k hours are well with in range if he would have the boat that long.* He would not have believed it without owning one him self.*
While the question that started this thread is about the life of gas engines, not diesels, I will add this little factoid to the diesel life discussion.* I dont't like the FL 120 for a number of reasons but longevity is not one of them.* A number of years ago I was having a phone conversation with Bob Smith of Ameican Diesel about the stock raw water pumps on our two FL120 and the best thing to replace them with.* In the course of the converstation we got around to the longevity of the FL120.* He told me that in recreational service, assuming regular use, proper operation, and proper service and maintenance, the engine should be good for 12,000 to 14,000 hours before needing a core overhaul.
He also told me that this engine was used in some of the Washington State Ferries way back when.* Not for propulsion, of course, but running pumps or generators, I don't remember which he said.* And these engines went some 25,000 hours before needing a core overhaul.* Of course, they were in near-contnuous service at a constant, conservative rpm.* And they received very frequent monitoring, servicing, and prompt mainenance when it was required.
More recently, I have a friend in Hawaii who owns, among other things, a small fleet of longline tuna boats.* These are mostly about 70 feet long and they go out for a month or so at a time, come home, unload, restock, and go right back out again.* They have one engine, a Volvo turbocharged intercooled dlesel which alslo provides hydraulic power for the longline gear, and a Northern Lights generator that powers the boats' refrigeration systems.* The propulsion engine is run the entire time the boat is at sea.* Maximum rpm used is 1,500 he said.* He has had these boats in operation for many years, and he said that he gets really pissed off if an engine goes less than 30,000 hours between overhauls.
-- Edited by Marin on Thursday 16th of February 2012 02:09:25 PM