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
Page 1 of 3 1 2 3 LastLast
Results 1 to 10 of 21

Thread: DD 6v92 problem

  1. #1

    DD 6v92 problem

    Iím running a pair of DD 6v92TA Covington conversion engines making 435hp each. Engine year is 1979. Last fall I had my second injector problem of the season on the stbd engine, so I put in a full set of injectors that I got from Scrod. I ran her a few times in the late fall, and again this spring with good results.

    This past Sun I headed out to go fishing and after 5 minutes of running (2050rpm) that engine bogged down and billowed out black smoke. After that it would only run up to about 1300rpm without smoking. I checked the turbos and they seem to be spinning smoothly. Does this sound like an injector problem to you guys or do you think I have something more serious? BTW, engine did not overheat, and oil pressure is fine.
    Everyone should believe in something - I believe I will go fishing - Henry David Thoreau

  2. #2

    Re: DD 6v92 problem

    Sounds like lack of air flow (turbo), but I'm no expert.
    Sky Cheney
    1985 53EDMY "Rebecca"
    ELYC on White Lake--Montague, MI

  3. Re: DD 6v92 problem

    That sounds like an airflow problem -- are you sure you didn't lose an airhose somewhere between the turbo and airhorn?
    http://www.denninger.net - Home page with blog links and more
    http://market-ticker.org - The Market Ticker

  4. #4

    Re: DD 6v92 problem

    I looked for hoses that might have slipped and saw none. I just spoke with a local "old timer" DD guy whom I respect, and he tells me that just spinning the turbo by hand may not tell me one is bad. Apparently sometimes you have to push in and spin to find the problem. He also said to look for excessive soot around the unit. I admit I only gave it a cursory look on Sun, so I'm going to give it a closer inspection tomorrow.

    Dan rebuilds the units himself, and I do trust him, but if it is a turbo, what are my options to purchase re: cost and dependability?
    Everyone should believe in something - I believe I will go fishing - Henry David Thoreau

  5. #5

    Re: DD 6v92 problem

    If you could get me a part number off the turbo itself I can explore some options for you.
    I want to live in Theory, everything works there.

  6. #6

    Re: DD 6v92 problem

    I'll try to find one tomorrow when I'm there. Would the engine s/n be of help? BTW, are the two (inboard and outboard) turbos identical or is there a "left" and a "right" turbo?
    Everyone should believe in something - I believe I will go fishing - Henry David Thoreau

  7. #7

    Re: DD 6v92 problem

    Your mechanic is right. It's what they do when running that matters. It does sound like a bad turbo. Get Derek a part number and see what he comes up with. The turbo can vary from year to year and between marinizers.
    Jack Sardina

  8. #8

    Re: DD 6v92 problem

    Check the emergancy air flapper is not open or stuck halfway.

  9. Re: DD 6v92 problem

    No air flapper on 6V92TAs that I've seen from that vintage. (Twin-turbo dry models) There should not be any soot around the unit; pull the blankets (cold engine only!) and have a look.

    What you're describing is a sudden failure rather than a slow degradation in performance so the problem should be pretty readily apparent on close inspection. If the turbos look ok one thing to check that is rare but possible is a collapsed baffle in the exhaust that is partially blocking it. Does exhaust flow look and sound the same on both sides at the dock?

    If the engine runs normally up to the 1200-1300 range its probably not a fueling-related problem (e.g. injectors, etc) and is much more likely on the air side.
    http://www.denninger.net - Home page with blog links and more
    http://market-ticker.org - The Market Ticker

  10. #10

    Re: DD 6v92 problem

    Blower? Air door shut down? Turbo bad? It sounds like something let loose or stopped the air flow. Check the air intake path and see if there is a blockage.
    Scott
    41C117 "Hattatude"
    Port Canaveral Florida.


    When I want your opinion I'll give it to you?

Posting Permissions

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