1986 25hp Mercury 2 stroke

Discussion in 'Outboard Maintenance' started by mcomikey, Aug 29, 2011.

  1. mcomikey

    mcomikey Well-Known Member

    Just bought a BFN Merc, still in the box, never opened. But just as the subject says: it's a 1986 !

    My question for the experts: Is there anything I should check before putting this motor in service ? Or just follow the manual ?

  2. Gramps

    Gramps Living & Dying in 3/4 Time

    Dry rot! Hoses, wires, water pump, gaskets, etc. Pop the hood & feel everything, it it seems off replace it. That's a heck of a find, how about some pictures?

  3. mcomikey

    mcomikey Well-Known Member

    Thanks, Gramps ! Gimme a day, I'll get some up.
  4. noeettica

    noeettica Well-Known Member

    Defiantly the water Pump ...

    I just changed a 30 year water pump but the old one was still very pliable ...

  5. mcomikey

    mcomikey Well-Known Member

  6. tom_in_orl

    tom_in_orl Founder of Microskiff, Member of the Gheenoe Army

  7. cutrunner

    cutrunner Cert. Yamaha technician

    Man thats cool! Love it when people find old stuff like that still new in the box.
  8. fsae99

    fsae99 I Love microskiff.com!

    Ok, I'm going to need to confiscate that. Please reply with your address so I can dispose of it properly. :D

    Great find. As Gramps said check any rubber or plastic parts for dry rot. Unfortunately only way to check water pump is to open her up. I would bet it is fine but why chance it.
  9. Snookdaddy

    Snookdaddy Well-Known Member

    Question: Where did you get it and do they have additional Merc 25hp for sale?

    I would replace the impeller as the vanes may have "set" from sitting for so long. Also, draining the lower unit and replacing the oil would be on my "to do" list. Check under the cowl for any problems (I bet everything is fine). Fire it up and follow "break in" instructions... Your a lucky guy to find a N.I.B. Merc. 25.

  10. Brett

    Brett > PRO STAFF <

    I've never run into a situation like this with an internal combustion engine, thought about it for a couple of days.
    A "never-been-used, still-in-box" 26 year old outboard gives me a few worries.
    Collector's engines get turned over at regular intervals to keep parts lubricated and moving.
    Are the rings going to be stuck to the cylinder walls due to galvanic corrosion?
    Are the electronics going to be reliable? Has crystallization of the cast metals started?
    How about ozone deterioration of plastics and rubber, is that a worry?
    Rifles I've seen, they were coated in cosmoline to keep parts lubed and protected. (royal pain to clean off btw)
    But are outboards from the factory packed for long term storage?
    Are the potted electronics intended to hold up for this length of time.
    Have the threads of the steel bolts dissolved the tapped threads of the aluminum components?
    I've purchased outboards that were garage queens, that required serious work
    before they were trustworthy enough for regular use.
    Not intending to be a buzz-killer, but I don't know enough to answer those questions.
    Anyone in the industry care to comment? Pro mechanics out there?
    I don't care if you're industrial, automotive, aircraft or marine, just looking for feedback.

  11. cutrunner

    cutrunner Cert. Yamaha technician

    Honestly, i would (before starting the motor) spray some 2 stoke oil in the cylinders thru the spark plug hole, change impeller, check wires and connections, check linkages(throttle, shift), change plugs, possibly gear oil, check fuel hoses. Then run it at intended break in procedure. Being that it was in the box helped a bit compared to just bein in a garage. Unless the box got really wet(i see a big stain in the picture). Honestly after you do my previous mentioned steps, all you can do is run it and see what happens. No sense in throwing too many parts at it before you try it. Oh, GReASE EVERY BOLT!!!!!!!!!
  12. noeettica

    noeettica Well-Known Member

    I purchased an aircraft engine like this one tore it down and re assembled ...

    To ensure complete peace of mind and value of the motor that would be the recommended route ...

    However I just changed out an Impeller on a 30year old motor and the old one was still like new ...

    I guess keep an eye on it ...
  13. fsae99

    fsae99 I Love microskiff.com!

    The electronics are rated for hours of use between Mean Time to Failure (MTF). I would think if this motor has not been dropped repeatedly over it sedentary life they should be fine.
    Cut's suggestion to oil the cylinders is a very good one.

    I'd like to see pictures of under the hood and through the spark plug hole. Inquiring minds want to know.
  14. mcomikey

    mcomikey Well-Known Member

    Back story first: Man I bought it from is in his 60's now.  He bought it with money left to him at his fathers death.  Turned out the motor was too big for his john boat, and bought a 15hp for it.  He said he couldn't bring himself to sell it at that time.  I told a friend I was looking for a motor, and he knew this guy. So, here we are today.

    Saturday will be the first chance I have to really get into this.  I will be sure to take some pics.  So far, just a quick look under the hood showed that hoses and wires seem new. Definitely like the idea of lube in the cylinders before cranking. The bag you see in the pic over the motor and the bag that contains the owners manual are like new, no degridation. May not be indicitive of the rest of the materials, but it was a good sign.

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