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keithahl's avatar
keithahl
Explorer
Oct 07, 2019

Blow-by Yamaha ef3000ise

Sigh...went to check the air filter on my yammy generator and found the filter soaked in oil. Maybe a hint of gas as well.



She has about 500 hours on it (the genset, not the filter)
Well taken care of, all the maintenance done on time, good gas etc.
No leaks or drips in the case.
Should I have expected less life than more on this thing? I was hoping for 2 or 3 thousand hours.

Rings?
Anybody ever pull one of these apart and hone out the cylinder and replace the rings?

Maybe its something else?

Thanks for any insights.
  • K Charles: I'll check the clearance and see what's what. Cheers.

    Chum Lee: Fair enough, but still pretty oily. I can squeeze it out from the paper filters foam edge. (not the sleeve, but the foam attached to the filter edges that seat against the housing). When I run a towel into the filter grooves it comes out oily. Not sure if that is the way it should be or not. Overreacting?...possibly. All I know is it had never done this prior. She is running fine, no smoke, or at least none that makes me worry. It starts fine, the output is fine.
    You know you are blowing my chances of convincing my wife we should have this:
    http://www.centralmainediesel.com/order/Perkins-6-kW-Diesel-Generator.asp?page=P6125


    I'll get another filter and see.
  • You might want to check the valve clearance just for good measure. If it's too tight you can end up with burned valves.
  • "Sigh...went to check the air filter on my yammy generator and found the filter soaked in oil"

    I wouldn't call that soaked in oil. If it was "soaked in oil" there would be oil dripping off the filter. A few drops will do that. How is the genny running? Oil consumption? Excessive smoke? Hard starting? Making rated power? If everything is OK I think you are over reacting.

    Do ALL the required maintenance and see what happens.

    Chum lee
  • If valve clearance is too tight, intake opens too soon and that's what you get.
  • I like shots in the dark that do not involve me having to gut this thing and hopefully do the ring job correctly AND get it back together in a timely manner.

    Or I suppose I could run it to death and finally just bite the bullet and get an 1800 rpm diesel...that will outlive me by a few decades.
  • I'm not really sure. It seems like it's possible if a valve isn't totally seating that some backwards flow could occure. Especially since you say it has the odor of fuel. And you've probably seen where gas dries up and leaves an oily residue behind.
    Just a shot in the dark!

    S
  • Hey Scott, I did! Which was an adventure...long story.
    Would out of spec valve lash create blow-by?
    (not a mechanic nor even remotely inclined this way...just too broke to pay one to do things for me)
  • All maint? Have you done the 300 hour valve adjustment?

    Scott