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Results 1 to 13 of 13
  1. #1

    Default upper shift shaft removal 1979 40hp

    can someone give me pointers on removing the upper shift shaft for replacement. motor is #5174633 40hp . the pins on the original are broken off where it connects to shift linkage. I have replacement part on the way. From what I can see, it appears the top pot metal part is roll pinned to the shaft? would I have to replace the whole unit, or can I just replace the top portion? Do I have to remove the power head?

    Thank you or your help

  2. #2
    Join Date
    Sep 2003
    Location
    New Tripoli, PA, USA!
    Posts
    16,751

    Default Re: upper shift shaft removal 1979 40hp

    It comes apart, but the power head has to be removed to fix it. Sorry.

    Jeff

  3. #3

    Default Re: upper shift shaft removal 1979 40hp

    Quote Originally Posted by fastjeff View Post
    It comes apart, but the power head has to be removed to fix it. Sorry.

    Jeff
    Thank you, Jeff. That is just what I was afraid of

  4. #4

    Default Re: upper shift shaft removal 1979 40hp

    So I got the new upper shift rod delivered today. There a few 2 pins and or legs to it. I think the longer one goes to the shift linkage. What does the other one connect to, I don't se anything for it to connect.

  5. #5

    Default Re: upper shift shaft removal 1979 40hp

    Help me out Jeff
    Last edited by Phillpc; 09-20-2019 at 09:44 PM. Reason: Wrong text

  6. #6
    Join Date
    Sep 2003
    Location
    New Tripoli, PA, USA!
    Posts
    16,751

    Default Re: upper shift shaft removal 1979 40hp

    Gonna need a photograph.

    Jeff

  7. #7

    Default Re: upper shift shaft removal 1979 40hp

    Here are the pictures
    Attached Thumbnails Attached Thumbnails Click image for larger version. 

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  8. #8

    Default Re: upper shift shaft removal 1979 40hp

    Well took it all apart, got the power head off, changed out the upper shift shaft and put it all back together. Hooked p the water hose and tried to start it. It only fired once but didn't start. Cranked on it awhile and primed bulb some more , still no start. I had to adjust the remote shifter and throttle cable quite a bit . To compensate for the previous engineering on the broken shift shaft.

    I'm wonder if adjusting the throttle cable may have change the spark advance or timing in some way? I took boat to lake last weekend and it started easy and ran like a top every time I turned the key. Now it won't start at all.

  9. #9
    Join Date
    Sep 2003
    Location
    New Tripoli, PA, USA!
    Posts
    16,751

    Default Re: upper shift shaft removal 1979 40hp

    Most likely you crapped up the carb (did you tip the pH upside down?) or fouled the plugs in trying to refire it. I suggest a shot of ether (starting fluid) to get her going. Had to do that myself just yesterday on my Mark 78, which is normally a good starting motor. It happens.

    Jeff

  10. #10

    Default Re: upper shift shaft removal 1979 40hp

    I laid it on its side to clean it up some. I'm going out this morni g to Check wires and make sure I didn't pull any loose. It does not act like it is firing at all

  11. #11

    Default Re: upper shift shaft removal 1979 40hp

    Went out this morning primed bulb and turned key, no choke or anything, it busted right off? That's great news to me , but now I wonder when is it not going to start next time?

  12. #12
    Join Date
    Sep 2003
    Location
    New Tripoli, PA, USA!
    Posts
    16,751

    Default Re: upper shift shaft removal 1979 40hp

    Come on! The poor thing's plugs were just fouled up.

    Have a little faith, man!

    Jeff

  13. #13

    Default Re: upper shift shaft removal 1979 40hp

    Quote Originally Posted by fastjeff View Post
    Come on! The poor thing's plugs were just fouled up.

    Have a little faith, man!

    Jeff
    Going to be getting a new set of plugs tomorrow. The ones in it are no the right plugs

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