Click for Honda Manuals, Parts and Model Guides!
Results 1 to 3 of 3
  1. #1
    Join Date
    Sep 2020
    San Francisco Bay Area

    Default BF50L milky gear oil, How many seals to replace?

    I have a Honda BF50L 5 HP that has milky gear oil, can someone let me know what seal to replace? Thank you

  2. #2
    Join Date
    Nov 2009
    temecula, ca., usa

    Default Re: BF50L milky gear oil, How many seals to replace?

    Typically you go for the prop shaft seal first. It's the one that fails most often. Especially if you never pull the prop and inspect for fishing line wrap. Fishing line wraps are the #1 cause of prop seal failure and frequent inspection and removal of line and debris wrapped around the prop shaft is the best way to prevent seal and thrust washer damage. It's a "routine" most experienced boat owners learn to keep up on to prevent problems.

    There is also a seal or seals for the main shaft as well as a seal for the shift shaft where they enter the gearcase. Those seals fail far less often.

    Other things to keep in mind are the oring seals for the drain and fill plugs. Although they don't look like a big deal, leaks do occur there and it's a good practice to replace them every time you remove the screws.

    The gearcase will build pressure as friction from the gears heats the oil. But, as the lube and air in the case cools down, a vaccum will occur at times and this will help water and air to intrude.

    Things like water temperature changes and leaving the case submerged can help increase this intrusion.

    Water and air being less viscous than the gear oil makes it possible for intrusion to occur while no oil leaks are apparent. So just because you don't see an oil leak doesn't necessarily mean that the case is fully sealed.

    Most COMPETENT shops will pressure and vacuum check the gearcase when diagnosing leaks or after any repairs such as seal replacement.

    Hope this helps and

    Good luck.
    Last edited by jgmo; 11-27-2020 at 03:42 AM.

  3. #3
    Join Date
    Sep 2020
    San Francisco Bay Area

    Default Re: BF50L milky gear oil, How many seals to replace?

    Thank you very much

Similar Threads

  1. BF8D - milky gear oil, seals to replace?
    By jaziniho in forum Honda Outboard Forum
    Replies: 6
    Last Post: 10-27-2020, 08:53 PM
  2. Broke skeg/gear cover on 1989 Johnson 25hp 2-stroke, to replace do i need new seals?
    By Harold Lee Miller in forum Johnson Evinrude Outboard Forum
    Replies: 23
    Last Post: 04-16-2018, 12:12 AM
  3. replace prop shaft seals
    By pia in forum Honda Outboard Forum
    Replies: 1
    Last Post: 01-17-2013, 03:44 AM
  4. 290 leg need to replace ram seals
    By mcw in forum Volvo Penta Gas Archive
    Replies: 1
    Last Post: 07-27-2009, 03:03 PM
  5. Replace seals on lower unit of 79 20hp mer
    By littled in forum Mercury Mariner Outboard Archive
    Replies: 2
    Last Post: 04-27-2009, 12:52 PM

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts