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Coolant leak after replacing heads

Discussion in 'Engine & Performance' started by chris44nala, Sep 10, 2019.

  1. chris44nala

    chris44nala Junior Member

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    Joined:
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    Location:
    Limestone County Alabama
    First Name:
    Chris
    Truck Year:
    1978
    Truck Model:
    GMC Sierra
    Engine Size:
    350
    Hi,

    So, I bought some heads for my 78 GMC and finally got the thing back together. All seemed well at initial startup. Oil pressure, good. Coolant temp good. Then my worst fears were realized. Billowing white smoke after a short drive. Got it home after fumigating the neighborhood and parked it.

    The question is what is the best way to determine where the leak is? Also, is it possible that it is an intake manifold gasket problem?

    Thanks for the help,

    Chris
     
  2. Frankenchevy

    Frankenchevy Supporting Member Supporting Member

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    Water in oil may be an intake manifold problem. But water in the combustion chamber points to head gasket or cracked head.
     
  3. chris44nala

    chris44nala Junior Member

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    Truck Year:
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    Truck Model:
    GMC Sierra
    Engine Size:
    350
    Thanks. Kinda figured. Pulling apart for a postmortem in a few days.
     
  4. Rusty Nail

    Rusty Nail Whatever!

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    You performed a final tightening during assembly? I would check the torque wrench before I started killing new gaskets. :killer:
    Absent sealer around the coolant passages is a big no-no :nono:

    If those checks fail..that's not promising.
    Good Luck.
    Hope this helps!
     
  5. Rickf

    Rickf Full Access Member

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    Air bubbles in the radiator is another indication of head gasket problems.
     
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