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Antifreeze shooting out exhaust manifold??

Discussion in 'GM Powertrain' started by jayfire, Feb 8, 2010.

  1. jayfire

    jayfire New Member

    I have a 99 vortec 350 that is blowing a big smoke screen. I just filled the radiator up with 2 gallons of anitfreeze and after 10 min I seen a steady stream of coolant coming from the passenger side exhaust manifold collector. Does that sound more like a head gasket or intake gasket problem?
    Thanks
  2. Stealth

    Stealth New Member 1000 Posts

    What tipped you off to this problem? did you try driving it and then the smoke came? And are you sure it's the antifreeze coming out, and not some other unnoticed problem? Just fishing for more information
  3. jayfire

    jayfire New Member

    It pushes out a big cloud of smoke at idle and even bigger over 1500 rpms. I topped of the radiator and ran it for a couple minutes and noticed a puddle under the pass side. I could see all the antifreeze in a nice little stream coming out of the collector. I just wanted to know if all that coolant is getting into the exhaust from the intake or the head. Thanks
  4. Dr Len

    Dr Len New Member

    Blown Head Gasket
  5. rotaryenginepete

    rotaryenginepete New Member ROTM Winner

    yup :grrrrrr:
  6. Aubio

    Aubio New Member

    I just rebuilt my 350 and started it today and its doing the same thing except the antifreeze is coming out the exhaust. all the head gaskets are brand new. first 30 seconds on them today when i started it.
  7. Gmcsuvguy

    Gmcsuvguy New Member

    When an intake is leaking the antifreeze will go into the crankcase (oil), when the headgasket is leaking it will go into the combustion chamber (piston top) and be blown out the exhaust.
  8. mateospeed

    mateospeed New Member

    do a compression check on the cylinders on the passenger side. Most likely, you'll find that one or more is low. If so, you've got a bad head gasket. If not, look for the intake mani gasket. Usually it won't leak into the cylinders, but it is possible. More likely a head gasket, though.
    -Matt
  9. judsteele

    judsteele New Member

    hope u didnt put dexcool back in it.i have been telling any body that will listen to me about that type of anti freeze and how bad it is for our motors and gaskets!!!!!! just my 2cents
  10. k.daddy1

    k.daddy1 New Member

    Before you go pulling off the heads, your describing a common problem with Chevy's. The 5.7 or 5.3 very seldom have head gasket problems. I have repaired close to 40 vehicles with leaking anti-freeze problems. It is typically on the passenger side of the engine, either the front or back water jacket seal between the intake and heads. If you have never had issues of the engine overheating in the past, I'm pretty sure you don't have a head gasket problem. Are you still running the orange anti-freeze in your vehicle? If you are, there is a possiblity you'll have to replace the intake itself becasue the corrosion caused by the anti-freeze. Then again you may get by with just replacing the intake gasket.

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