'95 Johnson - 30 hp

Discussion in 'Bubba's Outboards' started by WhiskerfishLou, Jan 24, 2006.

  1. WhiskerfishLou

    WhiskerfishLou New Member

    Messages:
    39
    State:
    Northeastern Indiana
    I have an lower unit lube leak from the small ports on the front side (boat side) of the lower unit. I replaced the lower unit lube this fall before winterizing it with Johnson lower unit lube and noticed a little weeping mostly out of the top port above the cav plate after running the fuel out at the ramp for part of the winterizing prep. It's a grayish color, like it would when water is in it. I took it out of storage this last week on a cabin fever binge. When I pulled it out, I noticed a good puddle of the gray gook on the top of the cav plate, as well as some tell tale signs out of the lower port below the cav plate. Suggestions, facts, and possible figures - pulease?!?. Somewhat mechanically inclined. I do have a shop manual, but it doesn't show these small port openings on the lower unit to give me a clue as to why the leakage or the purpose of these small openings... about an 1/8th inch above and below the cavitation plate. Thanks to all.
     
  2. Bubbakat

    Bubbakat New Member

    Messages:
    4,532
    State:
    McMinnvill
    It sounds to me like it is coming out of the seal under the water pump.
    I have some where in my files a way to pressure test those lower units in a barrel of water.
    You will have to remove the lower unit to do this but that ain't no biggie.
    I will look for that file I wrote the directions down on and post it for you.

    Resealing that lower unit ain't no biggie either.
     

  3. WhiskerfishLou

    WhiskerfishLou New Member

    Messages:
    39
    State:
    Northeastern Indiana
    I did drain it... didn't see any water, just this grayish lube... it was pretty thick too... it's in the lower 30's and upper 20's now. Thanks...
     
  4. Bubbakat

    Bubbakat New Member

    Messages:
    4,532
    State:
    McMinnvill
    When you changed the oil did you change the nylon gaskets behind the fill and drain screws?
     
  5. Bobpaul

    Bobpaul New Member

    Messages:
    3,039
    State:
    Supply NC
    It sure sounds like a leak in the upper seals with the grey lube drained out like what was seeping out of the small ports.

    I'd not take a chance on it and go ahead when it warms up enough to comfortably work and change the drive shaft and shift shaft seals

    The oil is formulated to absorb a small amount of water and still retain it's ability to lubricate = the grey color.
     
  6. WhiskerfishLou

    WhiskerfishLou New Member

    Messages:
    39
    State:
    Northeastern Indiana

    Interesting you should mention that. No I didn't... I'll have to check into that. Thanks.
     
  7. WhiskerfishLou

    WhiskerfishLou New Member

    Messages:
    39
    State:
    Northeastern Indiana
    Thanks for the insights. Do those seals have to be pressed off and on?
     
  8. WhiskerfishLou

    WhiskerfishLou New Member

    Messages:
    39
    State:
    Northeastern Indiana

    Thanks for your help. I will await your post regarding this subject. I kind of wondered about the waterpump getting wimpy... at idle the stream is weaker than it used to be. Maybe this is the cause of other things failing or showing signs of leakage.
     
  9. Bubbakat

    Bubbakat New Member

    Messages:
    4,532
    State:
    McMinnvill
    If you run in rivers a lot you need to change that impeller every spring. You need to replace the whole water pump every other year.
    The silt you encounter in a river will eat an impeller up in about 1 to 11/2 season.

    If the tell tell stream is weak at idle and you don't know when the last time the water pump was replaced you need to replace it.
    You can compare the cost of a water pump to the cost of a rebuilt power head and the water pump is always cheaper.
    Those seals aren't that hard to change. I have a sharp pointed awl I pop them out with.
    Every year you change the lube in lower unit change those gaskets out. That is the best preventive maintenance you can do down there.
    I have seen many lower unit destroyed because the oil was neglected.

    If the gray sludge was coming out the weep holes you need to replace both seals. One under the shaft and under the shift rod.

    I'll get that pressure test up for you here in a few.
     
  10. Bubbakat

    Bubbakat New Member

    Messages:
    4,532
    State:
    McMinnvill
    You can't normally tell by eye, if the seals need replacement. The best way to tell,is with vaccum and pressure testing the lower unit after the new impeller has been installed, and you are ready to bolt it back on.
    Most guys don't have the equipment for this, but a bicycle pump with a built-in pressure gauge,hooked-up to the vent or fill screws, can work as a makeshift pressure tester. Pump it up to 5-10PSI,and watch for a drop in pressure on the gauge. If it drops, stick the entire l/u in a garbage can filled with water,and pump it up again. Look for the bubbles. This will show you the bad seal or seals.

    Now this is the poor mans way to test one.
    You can take it to a shop and they if done right will pull a vaccum on it and it should hold for at least 45 min.
    One thig to remember is don't ever take the pressure up over 15 lbs That will surely blow a seal for you.


    Hope this helps wiskerfishlou:)