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92 series Detroit Diesels

Discussion in 'Engines' started by Oscarvan, Dec 2, 2015.

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  1. Oscarvan

    Oscarvan Senior Member

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    Didn't want to jack someone else's thread so here:

    There seems to be consensus that the 71 series are pretty stout engines. the 6-71 and 8V71 more so than the Turbos as those tend to have a limited life.

    I have heard less enthusiasm for the 92 series engine, 6-8-12V92....

    Anyone enlighten me?

    Thanks.
  2. Capt J

    Capt J Senior Member

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    Yes, they have o-rings for the cylinder heads and if the coolant isn't changed religiously every 2 years they can leak and you need a rebuild. If you overheat them, can crack cylinder heads as well. They don't tend to last nearly as many hours as 71's, especially if overpropped and many of them are. I'm not a big fan of them.
  3. Bamboo

    Bamboo Senior Member

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    Engines are only as good as the design, the operator, the conditions they are in and the maintenance they receive. All engines will fail if any of those four are sub-par. I've captained a vessel with a set of 16-92's which have both the blowers and turbo chargers for 11 years and they've given me relatively little problems and the boat has an active schedule. They are easy to work on, easy to find people to work on them, easy to find parts for and parts tend to be far less than new engines. That's my experience up and down the east coast of the USA.
  4. Capt Ralph

    Capt Ralph Senior Member

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    Where did the limited life comment come in on that other thread. The 92s use some of the same mfg's and similar equipment. AND, the same failures.
    I've got 37 year old turbos on my 71s.
  5. Capt J

    Capt J Senior Member

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    The 92's were really hot rodded by the marinizers, most of them had very large injectors and turbo's in retrospect compared to 71 series. The 92 series just does not last as long as 71 series. They also have the wet liners with o-rings that will fail and fill the cylinders with water if coolant isn't changed every 2 years. Same with the heads, they crack a lot more often compared to 71 series if overheated.

    Every 92 series boat I've ran/managed/maintained, the 92's lived a short life. I managed a 1991 58' Striker SF and by 2004 it was on it's 8th set of major overhauls. I ran a 1995 54' Hatteras with 12v92 DDECS, majored at 975 hours, blew port engine on survey seatrial at 1952 hours.
    Last edited: Dec 2, 2015
  6. Oscarvan

    Oscarvan Senior Member

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    OK, I sit corrected. That's why I ask these questions...... trying to enter the asylum with an educated mind. ;)
  7. g collis

    g collis Member

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    I like that, "trying to enter the asylum with an educated mind". As my friend Ralph always says. 71's rule.
  8. Capt J

    Capt J Senior Member

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    71's were good motors for their day, but I honestly think their day has passed. If they're in the boat you own keep them. BUT, the newer motors have so many advantages over the 71's. Cold starting, no smoke, less noise, smoother running, better alarm monitoring and engine safeguards, better engine monitoring with instant readout of fuel consumption, load, boost, EGT and on and on, and a clean engine room without grey walls and black bilges.
  9. Capt Ralph

    Capt Ralph Senior Member

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    Skippy J is correct. The newer engines offer so much for less weight, it is truly amazing what technology has offered the boating community.

    BUT, as J hinted to, if there running in your boat now, keeping them me be smarter.
    Re-powering with new technology will cost, maybe more than keeping up your old motors and their in-inefficiencies.
    I wish I could win the big lotto, That's what it would take to put in a new pair of QSM's.
    Till then, we love our 71s and will have them till?????

    On another thread, one of our best contributors IS re-powering 71s with QSCs. I do look forward to his reports.

    Till then, We have over come some of the negatives on our 12V71TIs.
    We don't smoke much when real cold. Won't smoke much at all if I remember to turn on the block heaters.
    Closed crank vents using Racors CCV system.
    Air box check valves and drain recovery bottles.
    Oil leaks addressed quickly.

    Usually, you can eat off of our drip trays.

    We are still over twice the weight of a newer 600 to 800 HP setup. This really sux fuel.

    The last 10 years and another 15+ may offer a good argument to re-power but not on a south Georgia budget.
    Parts are expensive for anything. 71 parts are still available. World wide, 71s may last another 20+ years.
  10. K1W1

    K1W1 Senior Member

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    I would like to have DD of the smaller variety I could wheel out of my shed and run up a couple of times a year to check the neighbours were still alive.
  11. Capt J

    Capt J Senior Member

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    6=71 Naturals are GREAT for that. I ran a 41' Viking with them that was so loud at hull speed you needed earmuffs on the flybridge.
  12. K1W1

    K1W1 Senior Member

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    Ideally I would like 53. An 8V would be a dream but I have to face facts that my shed is bigger than many peoples houses up where we are and it is already pretty full so something that does not need a full parking space is obviously more practical than one that needs a tandem trailer for a home
  13. RER

    RER Senior Member

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    How about a 485hp 671TIB? I ran a sportfish with a pair and it was the loudest contraption I ever drove.

    Also had a 36' Sportfisher with a pair of 6v53n's that weren't as loud but pretty close, and with a higher pitch.

    BUT MY HEARING IS JUST FINE... WHAAAT?
  14. K1W1

    K1W1 Senior Member

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    To get the full exhaust note out of one of those I would need to create a load with either a water brake or some mechanical contraption the size and cost of which makes this concept a non runner.

    If I have a smaller 53 series it could drive a saw or a smaller pump and achieve a similar earth shattering delivery.
  15. dennismc

    dennismc Senior Member

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    I had a 70's era gen set with a 4 cyl Waukasha engine , 4 stroke and when that thing was timed perfect, spot on injectors etc it gave off a rattle that would wake the dead, I had to make a hush cover for it. Great engine..
  16. Capt J

    Capt J Senior Member

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    Stick a generator end on it for your house. That would create plenty of load and good for a lack of electricity.
  17. K1W1

    K1W1 Senior Member

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    I have an 8 kvA 3 Ph Genset already for some 3 Ph toys I have. My electrical load is not great as when we want cooling we can open the doors which are in effect large parts of the house walls and when we want heating we light the fire which also heats the water and runs on free wood.
  18. chesapeake46

    chesapeake46 Senior Member

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    My friend put a 4-53 into an 80's Chevy pick up truck for fun.
    It is a screamer. Maybe he'd sell it to you for a grocery getter....
  19. K1W1

    K1W1 Senior Member

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    Is it painted Army green and has a You Tube video of it?

    While I can't say I am not interested, LHD of an 80's vintage is not the easiest thing to get on the road at home. I already have a couple of vehicles that are restricted to short journeys at 20mph on the road between properties.

    If he does want to sell it PM me some contact info I know another guy at home who is a Blazer fanatic and has done a couple of major repowers and rebuilds. A visit to his place would make anyone think he was growing some more given the number dotted around. Last time I was there he was storing firewood in one.
  20. chesapeake46

    chesapeake46 Senior Member

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    Not on YouTube, I don't believe.

    He would probably sell it. Last time I saw it, it was just sitting.
    He also did a 51 dodge power wagon, years ago, with a 3-53 ( i think ) and sold that to a local guy. You could hear him for miles.


    20140719_084240R.jpg 20140719_081505R.jpg 20140719_081514R.jpg

    And speaking of Detroits, the landing craft in the background had a couple 6-71's in her.