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  1. #1

    Default Installing lower unit

    1977 OMC Stern Drive model#981059, Engine 99023G . I worked on my lower unit and got stuck in the install to the intermediate unit. I only needs to go up about another 1/2 to 3/4 inch but it won't go. I don't know if I put a seal on wrong. It gave me trouble with installing it about 2 years ago and I just got time to get back to it. Any advice is appreciated. Alan
    Last edited by Alan S; 04-26-2020 at 01:16 PM.

  2. #2
    Join Date
    Jan 2017
    Salem Oregon

    Default Re: Installing lower unit

    I assume this is a stringer drive? (1977)..

    have you lubed it well? sometimes I seen problems where the spline cavity was filled with too much grease thinking it would squeeze out... but it doesnt, and causes the shaft from inserting fulling in to its pocket.... and you need to make sure the splines are aligned so they will engage and can be inserted fully.

    the only other thing that may prevent it from fitting up as it should, is if the water pickup tube is not seating properly...
    Last edited by centerline; 05-03-2020 at 03:32 PM.

  3. #3

    Default Re: Installing lower unit

    I'm not sure how to tell if it is a stringer. I was wondering about the grease yes I did grease it well. We wiped off what I could easily but it still won't go. Maybe we need to clean it off better yet. The splines are going on part way, we can see where the grease in the splines got pushed back. Should there be no grease at all on the splines and or the seals? Thanks for your advice, Alan

  4. #4
    Join Date
    Jan 2017
    Salem Oregon

    Default Re: Installing lower unit

    it needs a light coat of grease on the splines, but chect the watwer pickup tube to make sure its fitting in the hole correctly.... a lot of times they will catch on the edge of the hole and bend the end of the tube if its forced together... im not sure about the stringer drive, but most lower units have a pilot tube that is used to help line up the water tube so it goes into the hole without frustration...

  5. #5

    Default Re: Installing lower unit

    I apologize if I am describing this wrong it is the lower gear case not the lower unit if that makes a difference. It is a 4 stroke. I don't think it has a water tube other than what surrounds the shaft when it goes together. I guess I better really clean that grease off big time and try again. Thanks you and sorry if that was wrong info I gave you. Alan

  6. #6

    Default Re: Installing lower unit

    I cleaned the grease really well took the oring out and even warmed it up a little with a heat gun in case the remaining grease was too thick. It still won't go. It looks like the double seal part #43 is bottoming out on the one shoulder just from looking at the grease marks when I take it apart again.

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