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Results 1 to 10 of 10
  1. #1

    Default Milky lower unit oil

    Just did a complete once over on the '98 6hp I bought. Previous owner used it on his fishing boat so I wasn't to surprised when I took off the prop and found fishing line wrapped on the prop shaft.

    I'm not sure how long its been since he changed the lower unit oil, but of course some water came out followed by milky oil. I sprayed a bunch of WD-40 in before refilling with some Volvo Penta synthetic lube that I use on the big boat.

    What seals will I need to replace if this is an on going issue? I plan to drain the lube in a month or so to see how it looks.

  2. #2
    Join Date
    Sep 2010
    Location
    ontario
    Posts
    9,794

    Default Re: Milky lower unit oil

    Pressure test the lower unit to check the seals !-----------------------Costs a fortune if seals fail next week.

  3. #3

    Default Re: Milky lower unit oil

    Best place to pickup a pressure tester? All I have are lube pumps.....

  4. #4
    Join Date
    Sep 2010
    Location
    ontario
    Posts
    9,794

    Default Re: Milky lower unit oil

    Do not know----------Made my own 30 + years ago, still works just fine.

  5. #5

    Default Re: Milky lower unit oil

    I just discovered the same thing when I tuned up my 1998 25 hp Bigfoot. Is changing the seals something your average guy can do? I have a manual but I can't find anything on "seals" in the index. If this is something I can't do, exactly how much is a "fortune"? Thanks for any help....

  6. #6
    Join Date
    Sep 2010
    Location
    ontario
    Posts
    9,794

    Default Re: Milky lower unit oil

    Seals are " cheap "--------------If water gets in and ruins gears and bearings, then it costs a " fortune "-----------------Many dealers will only want to sell you a complete new lower unit or a new motor.----------------Look in the manual for " lower unit "-------------it has the details for seal replacement.

  7. #7
    Join Date
    Sep 2003
    Location
    New Tripoli, PA, USA!
    Posts
    12,619

    Default Re: Milky lower unit oil

    Milky oil is NORMAL if the motor was recenty run. That's merely air bubbles that have been beat into the oil. If water came out FIRST when you dropped the plug, then you'd have a problem.

    Jeff

  8. #8

    Default Re: Milky lower unit oil

    Thanks. Unfortunately it sat for a few days befor I drained it.

    It is leaving a small oil sheen on the water if I fill up a trash can and run it. Appears to be coming from where the propshaft housing bolts up to the driveshaft housing.

    Now to decide to fix or just sell it.

  9. #9

    Default Re: Milky lower unit oil

    Just got home and looked at it.



    Appears to be coming from that hole, not sure what it is as its not on any parts diagrams. Feels like its rubber when I try and stick a small screwdriver in the hole with a paper towel to try it up.

  10. #10
    Join Date
    Sep 2003
    Location
    New Tripoli, PA, USA!
    Posts
    12,619

    Default Re: Milky lower unit oil

    That's just combustion oil. Fill the LU to the top and go boating!

    Jeff

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