Click for Nordhavn Click for Lurssen Click for Apollonian Click for Apollonian Click for Abeking

Going to look at a 1981 Viking 46’ Sportfish with DD8V-71TI

Discussion in 'Viking Yacht' started by Tank, Jul 24, 2020.

  1. Tank

    Tank New Member

    Joined:
    Jul 24, 2020
    Messages:
    3
    Location:
    NJ
    Hi all I am new hear! Thanks any input!
    I am now in a 1984 Tiara 31 open and have two ft itis so Y not go big and get it over

    1st of all 8v71TI are they small for this boat?
    2 what should I look for you know soft deck wrought at windows ex ex.
    Thanks
  2. NYCAP123

    NYCAP123 Senior Member

    Joined:
    Mar 14, 2008
    Messages:
    11,218
    Location:
    Long Island, NY
    I'm going to guess they'll give you about an 18kt cruise, normal for the time. Today's boats average mid-20's. But you're used to those speeds with your Tiara. So if that's ok with you I like the old motors.
    The list of what to look for is too long to list. That's why surveyors are recommended, but bringing a moisture meter to check the hull and decks wouldn't be a bad idea. Pay special attention around stanchions and through hulls.
  3. Tank

    Tank New Member

    Joined:
    Jul 24, 2020
    Messages:
    3
    Location:
    NJ
    Thanks.
    I was hoping for 24knt.
  4. MBevins

    MBevins Senior Member

    Joined:
    May 23, 2008
    Messages:
    757
    Location:
    Windsor On. Canada
    Not in a million years.
    18-20 knts max cruise.
  5. Tank

    Tank New Member

    Joined:
    Jul 24, 2020
    Messages:
    3
    Location:
    NJ
    Hay I don't doubt you, just had some hope;). Thanks for your help.
  6. NYCAP123

    NYCAP123 Senior Member

    Joined:
    Mar 14, 2008
    Messages:
    11,218
    Location:
    Long Island, NY
    You're going to have to go deeper into your wallet. I can't think of any production SF from that era that'll cruise at 24kts. Maybe something like a Rybovich or something custom.
  7. Capt Ralph

    Capt Ralph Senior Member

    Joined:
    Sep 8, 2004
    Messages:
    9,813
    Location:
    Satsuma, FL
    Keep token, it may then feel like 24 kts..
  8. NYCAP123

    NYCAP123 Senior Member

    Joined:
    Mar 14, 2008
    Messages:
    11,218
    Location:
    Long Island, NY
    Now there's some good advice. It's great to be retired.:cool: Only thing to fear in a pee test these day is a report of high cholesterol. Still not while driving though.
  9. PFalkner

    PFalkner New Member

    Joined:
    Nov 13, 2020
    Messages:
    10
    Location:
    connecticut
    I am pretty sure I purchased the boat you speak of. When I left Port Washington she cruised at 15 knots at 1700 rpms and hit 20 knots at 2000 rpms which was full throttle. I think she would cruise a little faster if trim tabs were working. I love the boat
  10. Capt J

    Capt J Senior Member

    Joined:
    Jul 11, 2005
    Messages:
    13,930
    Location:
    Fort Lauderdale
    You are WAY over-propped. You need to see 350 more rpms at WOT. Is the bottom clean? If yes, it sounds like you either have a serious HP issue, OR are seriously over-propped, which will lead to a much shorter engine life. BUT, you also need to get the trim tabs working and do another seatrial.
  11. PFalkner

    PFalkner New Member

    Joined:
    Nov 13, 2020
    Messages:
    10
    Location:
    connecticut
    I think the props on the boat now are 3 blade 26 x 26 not sure if they are the correct ones. I could have a hp issue due to the fact that the injectors need to be replaced because at least four on the port engine are sticky. Did not have chance to check starboard engine. My plan is to replace all injectors. The trim tab issue is broken fitting on cylinder ,they are instatrim boat level brand not sure how to remove pins that hold piston to tab. boat is in water now. The boat seemed to ride very bow high. Any experience changing trim cylinders while boat is in water while not being a diver . when I purchased the boat it had not run in years. I got the boat running and made the 36 nm trip with no issue. Now I will start to correct everything "project Boat"
  12. Capt J

    Capt J Senior Member

    Joined:
    Jul 11, 2005
    Messages:
    13,930
    Location:
    Fort Lauderdale
    Fix injectors first. Boat levelers can usually be changed in the water by a diver since they have external hoses.
  13. PFalkner

    PFalkner New Member

    Joined:
    Nov 13, 2020
    Messages:
    10
    Location:
    connecticut
    I have 8 injectors now my suppler only has 6 left waiting for two . I was hoping to change trim piston by reaching in water from dingy will check how far a reach it is today .I don't want to pay for a diver. Not sure how the pins are held in place on the trim pistons
  14. Capt Ralph

    Capt Ralph Senior Member

    Joined:
    Sep 8, 2004
    Messages:
    9,813
    Location:
    Satsuma, FL
    Be sure to have all the injectors popped and matched before installing. Just picking up off the shelf is open for to many problems, regardless of the vendor.
    My past rants on this has always been rebuild what you have, at a shop that knows their stuff, that does pop and match.
    Again, tested, popped and matched before any injector goes in.
    Since your going to be down for a few days for a proper injector swap and tune up, take your time and do this right.
    I'm hoping you know, you don't just throw injectors in; height timing and rack & control tube travel requires a fine touch. Adjusting all the exhaust valves cold should be done at this time also.
    Don't forget new fuel pipes and all torqued to proper specs using the correct DD tools.

    If you know all this stuff, great.
    It is amazing how many folks don't.
    I have been there to fix Buba's work a few times.

    Use the serial number to get the correct injector also.
    Hatteras and Viking used to order some exotic engine tunes from DD marine vendors. Some strange injector sizes were used. Often, replaced with N90s in a rush or thinking to save on fuel.
    Again, Buba in the engine room.
    Last edited: Jan 5, 2021
  15. Capt J

    Capt J Senior Member

    Joined:
    Jul 11, 2005
    Messages:
    13,930
    Location:
    Fort Lauderdale
    I forget, I had boat levelers many years ago. But was easy to change in the water on my boat at the time....., connect the hose first before trying to connect the ram to the tab......
  16. Capt Ralph

    Capt Ralph Senior Member

    Joined:
    Sep 8, 2004
    Messages:
    9,813
    Location:
    Satsuma, FL
    I remember a tab job that went to pot. The hoses dissolved in my hands. 5200 was used to seal the hoses in the transom.
    Look them over well before starting the path of replacement while in the water.
    Out of the water may also reduce (eliminate) the ATF spill on the water also.
  17. PFalkner

    PFalkner New Member

    Joined:
    Nov 13, 2020
    Messages:
    10
    Location:
    connecticut
    I need to figure out what holds the pin in that holds the cylinder to the tab and bracket
  18. PFalkner

    PFalkner New Member

    Joined:
    Nov 13, 2020
    Messages:
    10
    Location:
    connecticut
    I have all tools required for Detroit, been a heavy equipment mechanic for 30 + years did use engine serial# to verify n90 injector
  19. Capt J

    Capt J Senior Member

    Joined:
    Jul 11, 2005
    Messages:
    13,930
    Location:
    Fort Lauderdale
  20. Capt J

    Capt J Senior Member

    Joined:
    Jul 11, 2005
    Messages:
    13,930
    Location:
    Fort Lauderdale
    Looks like your engine has the small injectors......or they were derated at some point in time.....most of the 8v71 TI's I've seen have the N110 injectors.......