Click for Detroit Diesel manuals!
Results 1 to 5 of 5
  1. #1

    Default 6v92 over heating

    HI everyone I have a pair of 1984 6v92 with a overheat proublum I have changed the impeller also sent the coolers out to be cleaned and changed the thermastats and if I put a heavy load on the engine a littel over 2000 rpms my temp gauge go's over 200 and the alarms go off if I dont push it the temp is fine is there something i am missing can any one help please

  2. #2
    Join Date
    Sep 2001

    Default Re: 6v92 over heating

    You need to look at the sea strainers, mit be pluging up.

  3. #3
    Join Date
    Nov 2009
    temecula, ca., usa

    Default Re: 6v92 over heating

    Hard to discern from what you wrote if it is both engines you are worried about or only one.

    200f is not overheating. 210f is considered the top limit and your alarm should start at 215f. Any engine protection you may have (murphy etc..) should shut you down at 225-230f.

    When I trouble shoot these problems, on one engine, the first thing I do is verify the temperature with an independent test gauge that I usually, if room permits, install in place of the temp sender. That way, I know EXACTLY what I'm dealing with and won't chase a ghost or my tail because of a bad sender. Your methods may vary, as they say.

    A couple of common problems that cause overheat, especially after a service are;
    Too much antifreeze in a closed system. Undiluted anti-freeze does not conduct heat very well. So, a mixture of over 50%/50% coolant to water will raise engine temps in hot conditions. Even in freezing conditions, 65% coolant is the max that should be used because pure antifreeze will actually freeze. Many people, including mechanics I've worked with, don't know this and I've seen 100% antifreeze used many times. If a little is good, then a whole bunch is better...right?

    If the seals in the thermostat housing were installed incorrectly or not replaced at all, that will cause precisely what you describe. The seals are fairly critical in directing all the coolant to the heat exchanger when the thermostats are fully open. if the seals allow coolant to flow through the by-bass at all times, the maximum amount of cooling can never be achieved. In fact, over heated coolant will be flowing directly back into the cylinder head at maximum engine load demands and will accelerate overheating.

    Then, there is the 1/3-1/3-1/3 rule about removing heat from an engine. The cooling system usually only removes 1/3 of the heat from the fire you are using to propel your vessel. Another 1/3 needs to exit the engine through the exhaust and another 1/3 is basically radiated into your engine space from the engine surfaces. I tell you this because a plugged exhaust or a very dirty engine will cause high coolant temps.


  4. #4

    Default Re: 6v92 over heating

    You need to check water supply and flows before and after sea water pumps, restritions are always present. ports on exaust risers! Because both are running hot its probably not internal. Its more likely the heat exchange issue. Flow is critical to cool in the exchanger. Exhaust Risers???

  5. #5

    Default Re: 6v92 over heating

    you need to check heat exchanger, *( fresh water cooler)

Similar Threads

  1. 6v92
    By flem111 in forum Detroit Diesel
    Replies: 2
    Last Post: 11-17-2009, 08:36 PM
  2. DD 6V92 TA Water Cooled Turbobs
    By joesig in forum Detroit Diesel
    Replies: 0
    Last Post: 08-19-2009, 11:35 AM
  3. DD 6V92 TA Rebuild costs
    By joesig in forum Detroit Diesel
    Replies: 2
    Last Post: 08-14-2009, 04:03 PM
  4. DD 6V92 vs 671TI
    By JimGibb in forum Detroit Diesel
    Replies: 1
    Last Post: 03-11-2008, 05:20 PM
  5. 6v92 fule consumption
    By dmeiners in forum Detroit Diesel
    Replies: 2
    Last Post: 09-21-2007, 10:16 PM

Posting Permissions

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