Welcome to the Hatteras Owners Forum & Gallery. Sign Up or Login

Enter partial or full part description to search the Hatteras/Cabo parts catalog (for example: breaker or gauge)
+ Reply to Thread
Results 1 to 6 of 6
  1. #1

    12V71Ti Life versus 8V92Ti ?

    In looking on the used markets, I'm seeing the 12V71Ti's in the 60+ ft. boats.

    How are the life spans on these versus the motors on the 53's and 58's? Any difference?

    Thanks!

  2. #2

    Re: 12V71Ti Life versus 8V92Ti ?

    Quote Originally Posted by Bob Quinn View Post
    In looking on the used markets, I'm seeing the 12V71Ti's in the 60+ ft. boats.

    How are the life spans on these versus the motors on the 53's and 58's? Any difference?

    Thanks!
    Nothing to add as far as life, but lots of 53's have 12v71's. I would think a mild tuned 12v71 would outlive a hopped up 8v92. Simply put each cubic inch is producing fewer ponies. Pretty much in every situation this is going to result in longer diesel engine life.
    SOUTHPAWS
    1986 52C Hull #391 8v92TI
    PENSACOLA, FL

  3. #3

    Re: 12V71Ti Life versus 8V92Ti ?

    Divide the HP into the displacement. The lower the ratio, and the further below 1:1 you can be, the longer the life span, in theory.

    Example: a "basic" 6-71 produces 216 HP..... 216/(6*71)=216/426=50%
    The 6-71TI produces 485 HP which is 485/426=113%

    Pretty clear the latter will have a higher chance of a coronary long before the former.

    But, and it's a HUGE but, that is of course subject to all else being equal. How was it run, and how was it maintained. A properly maintained and run TI has a better chance than a natural that was neglected and abused.

    So there is no simple answer to your question.
    1978 53' Motor Yacht "LADY KAY V"
    Hull number 524
    Chesapeake Bay

  4. #4

    Re: 12V71Ti Life versus 8V92Ti ?

    That all sounds logical. I will have to look at the HP's and displacements.
    Thank you!
    Bob

  5. #5

    Re: 12V71Ti Life versus 8V92Ti ?

    Different beasts. 71 series is a dry liner engine 92 is a wet liner. 92’s are easily damaged by overheating and poor coolant management. Most MY engines fail from poor maintenance and lack of use than hours. All these engines in charter or commercial use run far more hours than the weekend warriors
    "DON'T BELIEVE ANYTHING YOU READ OR HEAR AND ONLY HALF OF WHAT YOU SEE" - BEN FRANKLIN




    Endless Summer
    1967 50c 12/71n DDA 525hp
    ex Miss Betsy
    owners:
    Howard P. Miller 1967-1974
    Richard F Hull 1974-1976
    Robert J. & R.Scott Smith 1976-present

  6. #6

    Re: 12V71Ti Life versus 8V92Ti ?

    Quote Originally Posted by rsmith View Post
    Most MY engines fail from poor maintenance and lack of use than hours. All these engines in charter or commercial use run far more hours than the weekend warriors
    I'd say this is true with pretty much all marine diesels. Rarely does a rec user kill an engine due to hours, usually it's lack of cooling passage maintenance that leads to an overheat that kills them. The higher hp ratings have MUCH less room for error on cooling so lack of maintenance usually shows up much quicker on them than say a trawler or hull speed application.
    SOUTHPAWS
    1986 52C Hull #391 8v92TI
    PENSACOLA, FL

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts