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  1. #1

    Default 1979 mercury classic fifty dies when given a load

    I have a classic fifty its a 1979 refurbished in 2008 idles great with
    Miffs on once its in the water and I put it in gear it dies
    Any suggestions would be appreciated

  2. #2
    Chief Petty Officer 79Merc80's Avatar
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    Default Re: 1979 mercury classic fifty dies when given a load

    Are you sure about the year? As far as I knew, the "Classic Fifty" was made fron 86 on and rated at 45hp. But, I could be wrong.

    Craig
    There are Mercury/Mariner outboards and then there are Force/Chrysler outboards. There is no such thing as a Mercury Force, yes Mercury Marine built them, but it's still the old Chysler engine with updated electronics and a better lower unit, NOTHING MORE..


    How much horsepower can I have and still go to Heaven??

    1981 Glastron SSV194, MerCruiser 228hp (305 cid), 350 hours. Cuises at 3000 RPM / 30/31 MPH

  3. #3

    Default Re: 1979 mercury classic fifty dies when given a load

    I'm pretty sure of the year but I may be wrong

  4. #4

    Default Re: 1979 mercury classic fifty dies when given a load

    The motor is a 45 but the cover says classic fifty

  5. #5
    Petty Officer 1st Class
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    Default Re: 1979 mercury classic fifty dies when given a load

    What do you mean by "refurbished"? When a motor dies under load, it can generally be linked to fuel related issues. The other thing to check is your prop hub. A spun hub can cause issues as well. However, 3 years on a rebuild is awhile, especially if it wasn't well cared for after the rebuild. If you can get it in the water at the lake and run it, try squeezing the primer bulb while in gear. If the RPM's pick up as you squeeze the primer bulb, you have a fuel related issue.

    Also, make sure your gas tank vent is open. My motor will run on muffs with the vent closed, but in the water in gear it won't even try with the vent closed.

    Note: My suggestion above is based on my assumption that most of the electrical must be good if it is running well on muffs. I'd also recommend to put it in a large barrel full of water and run it. In a barrel, it won't hurt anything to run it at higher RPM's. Just make sure you don't run it above idle speed with only the muffs. The barrel full of water will help simulate some load from water pressure being on the lower unit. I would try that and see if you can get it to run above idle.

  6. #6

    Default Re: 1979 mercury classic fifty dies when given a load

    Thanks ill give those ideas a try

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