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Is my engine toast

Discussion in '1973-1991 K5 Blazer | Truck | Suburban' started by Adub, Sep 19, 2002.

  1. Adub

    Adub 1/2 ton status

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    I posted about valve guides and someone brought up the point that the engine may be on its way it. Its an 89 350 TBI with 124k, runs real strong, just smokes on start up after its sat for a few hours. Smokes when the truck shifts at high rpms, and when you turn real hard while on the gas. Sounds like a top end problem to me, am I right?
    Thanks
    AW
     
  2. Blue85

    Blue85 Troll Premium Member

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    Black smoke or blue smoke?
     
  3. Adub

    Adub 1/2 ton status

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    blue
     
  4. dyeager535

    dyeager535 1 ton status Premium Member

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    Even if it smokes, it doesn't mean its on its way out. It just means its worn, and could stand a rebuild IMO.

    The more wear you get, the more the clearances get excessive, the more problems you will have later on. If the crank starts slipping around in the bearings more, you may have to have it turned, whereas if it was pulled before the bearings got real loose, it may just need a polish.

    124K isn't a whole lot, and startup smoking is just a sign of worn valve seals due to the crappy stock seals. The engine smoke at higher RPM's I'd be more concerned about.

    If you are contemplating a head/TPI swap, it seems kind of pointless to spend time and money on valve seals, when you are just planning on replacing heads anyway. I'm in the same boat, my distributor needs a bit more work, but I'm not spending time and money on it, when the TPI distributor is going to replace the distributor in there now anyways.
     
  5. Sandman

    Sandman 3/4 ton status Author

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    Sounds like valve seals. You can put some umbrella seals on it and buy a lot of time.
     
  6. k5_beater

    k5_beater Registered Member

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    definatly valve seals. i currently have the same problem and it is only going to get worse. check and see if you have and oil on any spark plugs.
     
  7. Adub

    Adub 1/2 ton status

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    I just replaced the spark plugs and they were toast original 124k mile spark plugs. But they weren't carboned up or anything. Im worried it may need new seats too. Thats why I was contemplating the head swap. Other than disassembly, is there a way to tell if the seats need work?
    Thanks
    AW
     
  8. 76chevy

    76chevy 1/2 ton status

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    Don't waste your time if you are only going to replace the seals. Mine have been leaking for about 15 years. Some times it smokes sometimes it doesn't. It is only embarassing if it smoke really bad.

    If you are really worried, do a compression check on all cylinders. That will tell you if you need to rebuild or not. You could also try a top engine cleaner to clean out any carbon.
     
  9. 74Chev

    74Chev 1/2 ton status

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    These particular engines came from the factory with poor valve seals. It is extremely common an all of the throttle body injected engines until '95 to smoke on startup and consume 1-3 quarts oil expecially when the clock turns past 100k. Have seen many run past 200,000 smoking all the way. The bottom end is probably fine. Have a reputable shop rebuild the heads and run it.
     

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