Jet outboard is giving me fits!

Discussion in 'Bubba's Outboards' started by loanwizard, Nov 29, 2007.

  1. loanwizard

    loanwizard Well-Known Member

    Messages:
    3,297
    State:
    Coshocton,
    I have a 2007 Yamaha 4 stroke 115/80 jet. Not many dealers in Ohio know much about the jet part. I broke the aluminum impeller. Outboard Jets Inc sent me a new stainless steel one. I installed it once at .032 clearance, put it in the water and seem to be hitting the rev limiter, or it has a bad miss that does not occur at low speed. I reinstalled the impeller at .015 clearance and got the same thing. I am waiting on a call from an engineer at Outboard Jets inc, and was told by a service guy that seemed to know his stuff saying that with the stainless steel I may need a higher pitch impeller, in fact he is certain. I am afraid I may have damaged the powerhead. Any thoughts or things I should look at or is it all in the impeller?

    Thanks
     
  2. SkipEye

    SkipEye Well-Known Member

    Messages:
    7,525
    State:
    Winfield, MO
    Name:
    Darryl
    Don't know a thing about it Shawn but crossing my fingers for you that it will be a simple solution.
     

  3. jason454ci

    jason454ci Active Member

    Messages:
    1,307
    State:
    Zanesville, Ohi
    I wouldn't get to worried over it until you hear back from Outboard Jets. My theory is that the stainless impeller weighs more then the aluminum one did. Which may be causing it to hit a rev limiter on the powerhead. Not for sure if there is a rev limiter on it or not though. Sure sounds like there might be. On another note what caused the aluminum one to break? If something got up into it I'm not so sure I would want a stainless impeller in there. If the same thing happens again I'm guess something other then the impeller is gonna have to give. Probably won't be the prettiest sight either. Just a thought.
     
  4. Bobpaul

    Bobpaul New Member

    Messages:
    3,039
    State:
    Supply NC
    Try starting with basic engine diagnostics. Fuel, Spark, & Compression.
     
  5. loanwizard

    loanwizard Well-Known Member

    Messages:
    3,297
    State:
    Coshocton,
    Well, I spoke with the engineer and he told me to check the reverse cup, which I adjusted, I am not sure but I think I had the shoe installed backwards, anyhow I reinstalled everything and took her out. I hit the rev limiter @6200 RPM. I lowered the engine a notch and hopefully won't be sucking air. My next question is, if it doesn't work this time, Is there a poossibility of shaft slippage where the gear may be spinning at 6200 RPM, but the impeller isn't?

    BobPaul, the engine starts and idls and accelerates well, it just doesn't move the boat. I don't know how to do a compression check (That's why I have a warranty, although I am pretty sure my mechanic can do it too.... guess it's about time I learn) But we'll head that way next.

    BTW has anyone ever heard of a hydrofoil for a jet outboard?
     
  6. Dave L

    Dave L New Member

    Messages:
    1,012
    State:
    Minnesota
    Shawn, I don't know anything about outboard jets, though I was wondering if there may be a shear pin that got sheared some where between the jet and motor. You would think there would be to protect the motor from a lock up at the impeller. Are you getting any forward thrust while in the water?
    Also is the wear ring (the part surrounding the impeller) gouged or scratched?

    I would be careful as to how much work you do to the motor. I would hate to see you lose your warranty due to not being a certified mechanic.

    One more thing, why stianless? As jason454ci said, don't you risk breaking something else?
    Maybe you should change your handle from loanwizard to Gravel Slinger.:big_smile:
     
  7. loanwizard

    loanwizard Well-Known Member

    Messages:
    3,297
    State:
    Coshocton,
    Well, SS was more expensive and that means better right? It was recommended by Outboard Jets.

    It is supposed to not break like the aluminum did by a rock. It is supposed to help reguritate it better.

    Update: I dropped it a notch and got her on plane, but only after putting a person on the nose meaning it is now not an engine problem, but a weight distribution problem, or an engine height problem. Hopefully it will be taken care of today. I guess I can keep my baitwell full if I need to.

    I get to about 4500 rpm w/ just me in the boat before it becomes ineffective and runs up to the rev limiter @6200.

    I just got off the phone with the engineer and he told me to drop it another hole.... back to where it was when I bought it.... I think I am an idiot. I think it was just the foot installed backwards. :confused2:
     
  8. Stubby

    Stubby New Member

    Messages:
    208
    State:
    Kansas, Ar
    Shawn, you ain't no idiot! you're just going thru my learning curve. at 73 i'm about to make it full circle. See how much more you get to learn? LOL:big_smile:
     
  9. Dave L

    Dave L New Member

    Messages:
    1,012
    State:
    Minnesota
    Hey take it easy on your self. We all gotta learn sometime.
    Anyway good to hear ya got it all figured out.
     
  10. jason454ci

    jason454ci Active Member

    Messages:
    1,307
    State:
    Zanesville, Ohi
    Glad you got it figured out Shawn. The Stainless would still scare me though. They are right it won't break like the aluminum one did. But what is gonna break with the next rock?
     
  11. Bobpaul

    Bobpaul New Member

    Messages:
    3,039
    State:
    Supply NC
    BTW has anyone ever heard of a hydrofoil for a jet outboard?

    No hydrafoil that I know of. Install trim tabs on the boat.

    We used to make our own for airboats, using the rams that hold up a hatchback.
     
  12. rgmatt

    rgmatt New Member

    Messages:
    40
    State:
    Delaware River,Pa
  13. loanwizard

    loanwizard Well-Known Member

    Messages:
    3,297
    State:
    Coshocton,
    Update: Installed correctly the dang thing works, imagine that lol!

    It planes in approx 1/3 the time and seems faster (little).
    I am thrilled. :smile2:
     
  14. Netmanjack

    Netmanjack New Member

    Messages:
    3,734
    State:
    Ohio
    Thats great news Shawn! now we can get skunked quicker! lol:smile2::smile2::smile2:
     
  15. catfishrollo

    catfishrollo New Member

    Messages:
    6,894
    State:
    Ohio
    jack, you just made me spit`coffeye everywhere! lol...rollo