Buy Yamaha Outboard Parts

Announcement

Collapse
No announcement yet.

70hp 2 stroke pilot screw settings

Collapse
X
 
  • Filter
  • Time
  • Show
Clear All
new posts

  • 70hp 2 stroke pilot screw settings

    So I was wondering if anyone new the settings for the pilot screws on a 1993 Yamaha 70 2 stroke and if these were not at the right settings how would this effect performance thanks

  • #2
    that 70 uses a pilot fuel jet and a fixed pilot air orifice.
    the A/F ratio is not adjustable just the amount of the fixed a/f that is allowed into the intake is.
    1 1/4 turns is the book spec, I find 1.5 usually works better.

    Comment


    • #3
      Originally posted by rodbolt17 View Post
      that 70 uses a pilot fuel jet and a fixed pilot air orifice.
      the A/F ratio is not adjustable just the amount of the fixed a/f that is allowed into the intake is.
      1 1/4 turns is the book spec, I find 1.5 usually works better.
      Is that tightening all the way down then backing off 1 1/4?

      Comment


      • #4
        Originally posted by Dusky 13 View Post
        Is that tightening all the way down then backing off 1 1/4?
        Be careful with the tightening part. Just turn the screws in until they are lightly seated. Count the number of turns. Seems it should be one and one quarter turns for your model. Turn back out to the particular specification stated by Yam for your model.

        As rod bolt noted, it might idle better at one and a half turns out from being lightly seated. Or, maybe in just a bit more in than normal. All motors and carbs are not always the same.

        Comment

        Working...
        X