Welcome Guest - Sign Up today
Welcome Guest - Sign Up today


No announcement yet.

Yamaha 50 HP Head Gasket Replacement - How To

  • Filter
  • Time
  • Show
Clear All
new posts

  • Yamaha 50 HP Head Gasket Replacement - How To

    I have an '89 Pro 50 I lent to my best friends son to take out to practice for the Mark's Outdoors Tournament on Lay Lake outside Birmingham, AL and he undoubtedly blew the head gasket. I'm not upset, it could happen to anyone, just sorry it made for an unpleasant trip for him. It was running full speed and slowed down to a slow speed. It cranked, idled, discharged water normally, and ran fine at low speeds, but would not power back up to plane off the boat. He says he dropped in a local marina that put pressure on it and they said "Head Gasket".

    I am wondering if there is most likely other problems associated with this, even up to permenant head damage or is it possible just to simply replace the head gasket and keep on running. THis is the first Yamaha I've owned and wonder if this is a typical problem with them.

    I would also love to know the procedure neccessary to change it yourself if it is relatively simple.

    Much Thanks in Advance!

  • #2
    Re: Yamaha 50 HP Head Gasket Replacement - How To

    remove the head,check head surface flatness, clean block and head surfaces. DO NOT use a wire brush.
    reinstall with new head gasket and proper bolt torque.
    but while the head is off carfully inspect the cylinders for scoring.
    any scoring indicates an issue.
    and then you have to find the reason the gasket blew the first time or it WILL do it again.
    no tech questions by PM, they wont get answered.
    you have to be trusted by the people that you lie to .


    • #3
      Sign up today
      Re: Yamaha 50 HP Head Gasket Replacement - How To

      Thank you for your response rodbolt

      I am reasonably mechanical but haven't worked on a boat engine in a number of years. Are you familiar with the procedure for removing the head or would I be better off to get a manual.

      Any other comments or suggestions on this job and problem would be welcomed.

      Thank you in advance!