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Results 1 to 8 of 8
  1. #1
    Join Date
    Mar 2010
    Location
    Sydney Australia
    Posts
    7

    Default Engine runs but prop will free spin when in Gear 1979 40 hp

    Hi Guys,
    I just purchased a boat with a 1979-80 40 HP Mariner outboard.
    The problem i have is that is starts first go everytime but when i click it into either forward or reverse the prop will not spin. It free spins.

    I removed the prop to check the spline and all is good with that.

    What else would be the issue and what problems would i encounter if i dropped the bottom leg off. I don't have a manual so i don't know what will happen when i do this.

    If anybody could help answer these questions that would be fantastic thank you.

    Regards,
    Brad

  2. #2
    Join Date
    Sep 2003
    Location
    New Tripoli, PA, USA!
    Posts
    12,448

    Default Re: Engine runs but prop will free spin when in Gear

    First of all, you need to make damn sure the shifter is putting it in gear. Find out how it works on that motor--shift cable disconnected--before going any futher.

    Jeff

  3. #3
    Join Date
    Mar 2010
    Location
    Sydney Australia
    Posts
    7

    Default Re: Engine runs but prop will free spin when in Gear

    Hi Jeff,
    I had the cable disconnected with the motor cover off. The shifter will go forward and back manually, all the linkages move but nothings seems to engage.

    Thanks Jeff

  4. #4
    Join Date
    Mar 2010
    Location
    Sydney Australia
    Posts
    7

    Default Re: Engine runs but prop will free spin when in Gear

    Hi Jeff,
    Also here is the Serial # etc 40 40BE serial # 676 B 404523
    This might help, do you where i can get an electronic manual for this model.

    Cheers
    Brad

  5. #5
    Join Date
    Jun 2007
    Location
    Colorado Springs, CO, USA
    Posts
    169

    Default Re: Engine runs but prop will free spin when in Gear

    does it spin freely with a touch of your hand, with the engine OFF of course?

    If so, then sounds like your shaft is broken!!! If it will slip with a little pressure on it, then your Prop Hub is done and needs to be replaced.
    '74 Glastron Carlson CV16, '76 Merc 1500 ELPT

  6. #6
    Join Date
    Mar 2010
    Location
    Sydney Australia
    Posts
    7

    Default Re: Engine runs but prop will free spin when in Gear

    Hi Paul,
    Yes with the motor in gear and engine off you can spin the prop. What sort of dollars do you think i'll be up for with either of those issues being the case??
    Are these hard to fix?

    Thanks,
    Brad

  7. #7
    Join Date
    Dec 2009
    Location
    Rineyville, KY, U.S.A.
    Posts
    217

    Default Re: Engine runs but prop will free spin when in Gear

    Getting the prop rehubbed isn't hard you just pull it off and take it to a prop shop. If the shaft is broke you are looking at a lowerer unit rebuild. The pprop will be $100 bucks on up, and the shaft I have no idea on cost. Alot of it will depend on whether you do the work yourself or have it done at a shop.

  8. #8
    Join Date
    Dec 2009
    Location
    Yuma, AZ, USA
    Posts
    107

    Default Re: Engine runs but prop will free spin when in Gear

    I would take the lower unit off and with a soft grip vise grip and try to shift it into forward or reverse.If nothing happens your shift cam may be at fault.this requires you to take the guts out of your lower unit and see.May also be your shift pin in your prop shaft.The shift cam pushes the shift pin on your drive shaft to engage and disengage f. & N. & R. If your lower unit is messed up fixing it yourself can be a real pain.Depending on what is messed up and buying these parts and fixing this yourself I would recommend looking for a decent one eBay.
    [FONT=Impact]Best Regards[/FONT]
    [FONT=Impact]Steve[/FONT] ;)

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