why an 1976 15hp johnson 2-stroke pee out of exaust?

Discussion in 'Outboard Maintenance' started by Flyline, Jan 13, 2010.

  1. Flyline

    Flyline Won "Do More With Less" Award!

    I just bought a 1976 johnson 15hp 2-stroke tiller short shaft for cheap. I just bought it for my camo highsider and plan to camo paint the motor.

    I never own this kind of motor but a good things about it.

    So anyway.....

    Curious to ask....how reliable is the motor?

    Compression, lower unit check, and everything is working excellent.

    I'm curious why the motor pee out from the exaust?? Instead out of the tube like the new ones?

    Is any website information about this motor?

    Where I can find parts for it? With pictures?

    Any of you ever owned this kinds of motor?

    I took it out on the lake with my bare hull 15.4 highsider and it's haulass.

    Plan to put a jackplate and tabs soon.

  2. Brett

    Brett > PRO STAFF <

    Had a '74 15.
    Water blows out the exhaust relief because the
    engineers hadn't figured out the whizzer tube yet.
    Tuff motor as long as it hasn't been abused.

    Finding parts will be either an online search or salvage shops.

  3. Gramps

    Gramps Living &amp; Dying in 3/4 Time

  4. Flyline

    Flyline Won &quot;Do More With Less&quot; Award!

    Thanks for the great info! That's nice website with all the details.

    That's why my oldie motor has no baffle in the exaust which is loud motor to run.

    Thanks again.... :)
  5. Un-shore

    Un-shore Well-Known Member

    No pics? Why won't you show us your johnson?
  6. Flyline

    Flyline Won &quot;Do More With Less&quot; Award!

    My computer just crashed... :mad:

    I'm on my I-phone but I can sent u email if u like.
  7. Brett

    Brett > PRO STAFF <


    I always enjoy a good bring back!

  8. Un-shore

    Un-shore Well-Known Member

    Thank you, I'll be here all week! Try the veal. ;D
  9. Flyline

    Flyline Won &quot;Do More With Less&quot; Award!

    Lol....you're crazy......

    I forgot to show my smiley on my last post... ;).
  10. Flyline

    Flyline Won &quot;Do More With Less&quot; Award!


    My 76' 15hp johnson been running great so far but one thing about the motor is bothers me.

    U know how the motor with exhaust relief sputter out with water plenty when it's idle. (No pee hole)

    When I give it half throttle to WOT then there's no water sputter out of the exhaust relief. I put my finger on the exhaust hole and it's sucking my finger in the hole! Sometmes the water pour out of the exhaust hole when running.


    Why does the motor do that?

    It's doesn't get hot or anything.....just being warm aftern I had been running WOT for 40 mins.

    Any ideas?? Hint hint?
  11. HighSide25

    HighSide25 Well-Known Member

    your motor doesnt spit, it sucks!
  12. Brett

    Brett > PRO STAFF <

    Running at planing speeds, a low pressure area forms behind
    the hub of the propeller. Exhaust pressure from the engine
    is not enough to equalize this pressure difference. So it draws
    in additional volumes of air through the pressure relief port to
    try to equalize the pressure difference.

    Therefore your engine sucks, but only at high speeds.  ;)
  13. Flyline

    Flyline Won &quot;Do More With Less&quot; Award!

    Is that normal? Now I know my johnson likes to be sucked. ;D ::)