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Results 1 to 4 of 4
  1. #1

    Default oil is leaking from around the

    oil is leaking from around the prop what coud be
    the problem. 1991 model 40hp

  2. #2
    Ken Denman's Avatar
    Ken Denman Guest

    Default The prop shaft seal is most li

    The prop shaft seal is most likely gone. The age of your motor would indicate from high wear activities such as running in sandy water or ingesting fishing line.

    It will need replacing.

  3. #3
    MERC FAN's Avatar
    MERC FAN Guest

    Default "The seal on the Prop Shaft is

    "The seal on the Prop Shaft is certainly a likely cause. However, before commencing any work, I suggest you consider the following: Sometimes engine exhaust and two stroke oil residue dripping down from the exhaust stack inside the column, can cause you to believe the gearbox seal is leaking.

    If the leaking oil is very dark in colour it is highly probable that it is exhaust residue.As a double check, loosen the lower gearbox drain screw, the oil that drips from there will be either a nice translucent looking colour or a whiteish opaque colour.
    If it is whiteish, it is indicating water has entered the gearbox through the worn seal and the internal gears turning at high speed have emulsified the oil with the water. If thats the case, you will need to have the seal replaced and the gearbox thoroughly flushed prior being refilled with fresh oil."

  4. #4
    Join Date
    Mar 2006
    Harrison, MI, U.S.A.

    Default "I had a similar problem with

    "I had a similar problem with my '95 Merc 40 h.p. 4 cylinder. gear oil leaking around the prop. I replaced the o-ring on the shaft carrier assembly but now after putting everything back together I don't have reverse anymore, just forward. Any clue as to what I did wrong? thanks in advance"

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