yamaha 25 2 stroke compression specs

Discussion in 'Outboard Maintenance' started by jmrodandgun, Aug 11, 2014.

  1. jmrodandgun

    jmrodandgun Well-Known Member

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    Does anyone know what the compression should be on a 08 25 two stroke with pull start only?
     
  2. cutrunner

    cutrunner Cert. Yamaha technician

    120 max. But every guage is different
     

  3. jmrodandgun

    jmrodandgun Well-Known Member

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    Hmmmm. I have a cheap harbor freight gauge I borrowed and both cylinders are showing about 95-100 psi. It seems a little low but I didn't know if it was because of the pull start only or if the gauge was just junk. I did the test cold with both plugs out and again with only one plug out. Given that they are both dead even, I assume the motor is probably fine. The motor is somewhere in the 400 hour range and suffered an overheat from a clogged water intake in some grass.

    It starts on the first pull and seems to idle just fine. Speed and RPM is consistent.

    Trying to decide if it's worth investigating further or just run it like it is.

    edit- I was reading the gauge wrong.  ::)
     
  4. jmrodandgun

    jmrodandgun Well-Known Member

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    There is a little water coming out of the upper exhaust ports just below the cowling. I'm assuming this is normal, if not maybe a sign of a bad head gasket?

    [​IMG]
     
  5. cutrunner

    cutrunner Cert. Yamaha technician

    Its normal. Leave it alone and just use it ;)
     
  6. jmrodandgun

    jmrodandgun Well-Known Member

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    Thanks dude. That's what I figured. [smiley=alcholic.gif]