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Highest engine hours without rebuild???

Discussion in 'Chris Craft Roamer Yacht' started by raemore, Dec 31, 2009.

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  1. raemore

    raemore Member

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    Was wondering what is the highest engine hours anyone has heard of without rebuild....with engines still running????
  2. Henning

    Henning Senior Member

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    Define rebuild.... I've run 20-645-E7 EMDs with over 200,000 hrs on them (25 years commercial operation) that never had the cranks out, but they had received quite a few power pack changes which consist of connecting rod, piston, cylinder and head.

    Edit: I just noticed this is in a CC Roamer forum so I'm going to guess you're looking at a gasoline engine, probably a BB Chevy or Ford. If you use it regularly, you should be able to get 3000+ hrs TBO. The worst thing is for the engines to sit though, so any extended periods of inoperation will cut into that.
  3. K1W1

    K1W1 Senior Member

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    I would hazard a guess that even if the cranks were never pulled that the main bearings were done a few times in that period of time along with Lube, Fuel, Coolant Pumps, Camshafts along with associated bearings and of course the ubiquitous EMD Injectors would have had some attention too I should imagine
  4. Fishtigua

    Fishtigua Senior Member

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    I thunk that a single cylinder Swedish Fireboat/Tug from 1912 came along side us in the US VI.in 1986 . They burned their own decks to get across the pond.

    Hours ? Just a few thousand.

    Crew?

    Blonde, Scandies, Mad as Hatters and still live across the street from Mum
  5. raemore

    raemore Member

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    200,000 hrs

    impressive!!!
  6. Henning

    Henning Senior Member

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    Yep, but then, that's why I said "Define Rebuild". All of those issues even cumulatively I consider repair and maintenance. My personal definition of a rebuild will include a line bore and crankshaft service.
  7. Capt J

    Capt J Senior Member

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    In a smaller boat, I know of a lobster boat around 40' that has a cummins triple nickel and last I heard was at 31,000 hours with nothing done to the bottom end of the motor. The heads had been rebuilt 5 times and the turbo's 7 times. But the owner never really ran her over 1400 rpm's.
  8. K1W1

    K1W1 Senior Member

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    Hi,

    Would you care to enlighten the engineers on this forum why a line bore would ever be required as part of a rebuild?
  9. K1W1

    K1W1 Senior Member

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    Hi,

    You should enter that in the Guinness Book of Records for the longest living 555 known to mankind
  10. Capt J

    Capt J Senior Member

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    Well, anything is possible. I ran a 38' Bertram with 555s that had 8000 hours without a rebuild or anything and they passed survey and ran fine, they were naturals.

    I also had a friend that had a 28' Pacemaker he bought from the origional owner and it had a single 307 chevy in it (I think that's what it was), and it had 6000 hours and it too was all origional but the guy never ran it over 1200 rpm's.
  11. Norseman

    Norseman Senior Member

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    Perkins 4-108 installed in a CSY 37 sailboat operated as a charter/training boat in St. Croix and still is:

    The owner had the engine overhauled after 15,000 hrs just because the hours made him nervous: Nothing wrong with the engine, it kept ticking and licking forever.
    (the same engines are used in London taxi-cabs for the same reason: They last forever)

    Good news for me: Got the same Perkins 4-108 in my sailboat, only 5000 hours on it so far and it may be ready for an overhaul in 10,000 hours, or 40 years from now...I would be 93 years old then and perhaps ready for a trawler or just move ashore and take up residence in Brazil where the young girls can appreciate a smooth running guy with lots of hours but no wear or tear on him...:D
  12. Marmot

    Marmot Senior Member

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    The engine will probably be just fine but your injection system might need some work by then.
  13. Henning

    Henning Senior Member

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    Because the bores get elongated and sometimes blocks will shift and the main journals will get out of line so the caps get milled, and the main journals get line bored so the crank will spin in the bores when new bearings are installed. It's pretty typical that when an engine gets an overhaul that it gets a line bore. Hard to understand an engineer arguing with that item.
  14. Capt J

    Capt J Senior Member

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    I have overseen some rebuilds on diesels where they needed to be bored (cylinders). Most have not needed to be bored. Some Detroits and such cylinders were never bored properly from the factory. But, also if the engine has ever gotten hotter then normal and cooled off or something to that effect it could egg shape the bore a few thousands. If the motor has ever been run without oil, or started a few times without being run in a very long time, sometimes the crank journals need to be align bored (this is usually rare).
  15. K1W1

    K1W1 Senior Member

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    Hi,

    If you actually knew what the **** you were talking about it wouldn't be.

    Line boring ( The re boring of the block to assure crankshaft position) normally occurs when an errant operator has let his engine run so long that the upper Main Bearing Shells have started to fret in their housings or there has been a catastrophic failure of cylinders(seizure) that resulted in a block shift.

    It also normally involves the use of special bearings as the housings wre no longer standard size.

    It is something I am sure you have seen if you have as you claim seen EMDS with 200,000 hrs on them without the cranks being maintained.
  16. 61c40

    61c40 Member

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    Cat D375

    I was associated with a Caterpillar D 375 that had 68,000 hours on it. The application was on a 66 ft us army t-boat built in 1953, hull # T465 it was the main propulsion eng it had a dual sump & dual pump with a 76 gal oil capacity complete wih a 16 filter remote oil filter system w/a raw water cooler. At 1000 rpm it caused a unpleasent vessel harmonic! At 980 rpms it produced 270 shp propelling the 100 ton full displacment vessel at very smooth 10.4 knots. the main bearings and pistons were never touched the heads were rebuilt 4 times. The vessel was always operated in fresh water, burned 11.5 gal a hour w/gen, the oil always Amaco 300 40w was changed every 1000 hours.
  17. K1W1

    K1W1 Senior Member

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    Hi,

    The old Pre Combustion Engines were tough old units alright.

    I did two transatlantic runs on a yacht that had a pair of D 399's in her, when it was time to start if there was not too much smoke coming up from the pre heater wiring she would always burst into life immediately.

    Last time I was on her there was a funny noise in the Stbd one now and again, it turned out that the Main Bearings had worn through to their Copper Backing and the Crank Deflections were abut 4 times the max allowed by CAT. Lucky the Crank didn't break.

    They had done 22,000 hrs and according to Maintenance History onboard only had heads off once prior to this little issue.

    I was also on an old girl with D 353's in her, one had a Charge Air Cooler failure underway and a cylinder filled with water blowing the head gasket out the side and it didn't bend the rod.

    Only major complaint with both of these boats was the amount of stuff that used to get thrown out of the exhausts (both were dry stack).
  18. SeaEric

    SeaEric YF Historian

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    In keeping with the Chris Craft Roamer forum theme of this thread, I will attempt to answer this question with some personal experience and observations relative to non-commercial applications.

    As was suggested in a previous response: Diesel engine hours have less to do with longevity than how the engines were used and run. If run at lower RPM's for many hours as opposed to being run near max RPM's for a shorter time. A diesel engine surveyor once told me to consider total number of gallons of fuel passed through an engine as opposed to total engine hours. This was in the context of a survey on a pair of GM 6v92's @ 550 HP. The engines had 2500 hours on them. 6v92 550's can be all done at 1200 hours in sportfish application when they are run balls to the wall all the time. The engines in question were perfectly healthy at 2500 hours. The mechanic suggested that they had likely not been run over 1500 RPM's, ever.

    I have seen 3160 and 3208 Cats, naturally aspirated (non-turbo, lower HP) with 8 to 10K hours on them still running fine. Same with the 6 cyl Lehmans.

    On gasoline engines, life expectancy is little more of a wild card. I have seen Chrysler 318's quit at 5000 hours. You regularly see the old 427ci/300 HP Chris Crafts and 454 ci/350 HP Crusaders with 1200 to 1500 hours and more, still running fine.

    On pleasure boats, typically lower hours and a lack of use on older engines can present more of a problem than higher hours.
  19. K1W1

    K1W1 Senior Member

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  20. 61c40

    61c40 Member

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    Yes it does there were so many of them built that I,m amazed that more wern't converted they came from a variety of builders with three different main eng configurations Budda, twin bank 6-71s and the cat ,the one I 'm familiar with was built a Missouri Valley Steel In Levenworth Kansas. Ballasted correctly they were a pretty good sea boat and could stop a 51 caliber WARSAW PACT Round if things got hairy!!!