advice: 2004 merc water pump impeller change now stuck in forward

Discussion in 'Outboard Maintenance' started by matauman, Jul 23, 2015.

  1. matauman

    matauman I Love!

    Decided to change my water pump impeller on my 2004 mercury 2 stroke 60 hp. 
    After completing the process (following directions from the mercury manual) specifically: placing shift lever in forward before removing lower unit, upon re-assembly the prop would only go forward. 
    I assumed I had misaligned the spines on the shaft for the transmission and which in the final analysis was correct.
    But in trouble shooting I learned a few things:
    First it's amazing how little rotation exists in the movement from forward to reverse in this spine shaft, like 2 teeth.  Second the spine shaft on the lower unit had approximately 200° of free rotation and I thought I had broken the cam inside the lower unit. 
    Upon further analysis, and encouragement from wise neighbor, by taking a pliers and rotating this spline on the lower unit past the end of its free travel I was able to shift into neutral and reverse.
    You can spin the drive shaft while moving the spine on the lower unit.
    I located the spline and on the lower unit fully counterclockwise and reinstalled the lower unit with the shift lever in forward and it works fine now.
    I was about ready to bring it to a shop and start drinking!
    But really wanted to be able to do this on my own just in case and now feel comfortable in the process.