GM Truck Club
THE PREMIER CHEVY TRUCK & SUV FORUM
Founded in 2004 ~ We're the #1 Chevy Truck & SUV Forum.
Silverado & Sierra | Tahoe & Yukon | Suburban & Yukon XL | SUV & CROSSOVER

Antifreeze shooting out exhaust manifold??

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

  1. jayfire

    jayfire New Member

    Joined:
    Nov 21, 2008
    Messages:
    8
    Likes Received:
    0
    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
    #1
  2. Stealth

    Stealth New Member

    Joined:
    Jul 5, 2009
    Messages:
    1,324
    Likes Received:
    0
    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
    #2
  3. jayfire

    jayfire New Member

    Joined:
    Nov 21, 2008
    Messages:
    8
    Likes Received:
    0
    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
    #3
  4. Dr Len

    Dr Len New Member

    Joined:
    Sep 15, 2009
    Messages:
    103
    Likes Received:
    1
    Blown Head Gasket
    #4
  5. rotaryenginepete

    rotaryenginepete New Member

    Joined:
    Nov 11, 2008
    Messages:
    285
    Likes Received:
    3
    yup :grrrrrr:
    #5
  6. Aubio

    Aubio New Member

    Joined:
    Feb 8, 2010
    Messages:
    4
    Likes Received:
    0
    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.
    #6
  7. Gmcsuvguy

    Gmcsuvguy New Member

    Joined:
    Dec 22, 2007
    Messages:
    279
    Likes Received:
    1
    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.
    #7
  8. mateospeed

    mateospeed New Member

    Joined:
    Apr 15, 2009
    Messages:
    47
    Likes Received:
    0
    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
    #8
  9. judsteele

    judsteele New Member

    Joined:
    Oct 9, 2009
    Messages:
    37
    Likes Received:
    0
    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
    #9
  10. k.daddy1

    k.daddy1 New Member

    Joined:
    Jul 25, 2008
    Messages:
    112
    Likes Received:
    1
    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.
    #10
  11. mateospeed

    mateospeed New Member

    Joined:
    Apr 15, 2009
    Messages:
    47
    Likes Received:
    0

    Very good points. Unless you've severely overheated the engine, the likelihood that you've ruined the head gaskets is very low. The likelihood that you have a bad intake mani gasket is, however, very good. I'd at least start there, since you'll have to pull off the intake either way you go!

    -Matt
    #11
  12. BlueEagle

    BlueEagle New Member

    Joined:
    Feb 12, 2010
    Messages:
    30
    Likes Received:
    0
    Like stated previously. If antifreeze is getting into your oil you have a bad intake gasket. I had this problem in my 1997 Malibu becuase of that great coolant called DEXCOOL, it ate away at the LIM gasket and cuased a big old mess. Check your oil level if its real high the coolant is in with the oil. You can sometimes smell the DEXCOOL as well.

    Again this is assuming your still running DEXCOOL in your engine. If you do proceed with changing the gaskets. see if they have came out with a revised intakes gaskets, I know they did this for the 3100 and 3400 V6s they are rubber and metal gaskets, then just rubber that came from the factory, and make sure to completely flush the old coolant out before putting in new. I dont know if the same applies to the V8s.

    For the Malibu I bought my new gaskets from Flepro, if that help narrows a sreach down.
    #12
  13. cpon2009

    cpon2009 New Member

    Joined:
    Feb 15, 2010
    Messages:
    8
    Likes Received:
    0
    If you got coolant in your exhaust then there is a major possiblity of a cracked or warped head
    #13
  14. Aubio

    Aubio New Member

    Joined:
    Feb 8, 2010
    Messages:
    4
    Likes Received:
    0
    Well that's what I thought but as it turns out I finially got around to taking the manifolds off and there was no water coming from either side. I drove the truck around a bit when I was putting it in the shop and the water got into the cadaletic converter from the first blown head gasket. Thanks for the suggestionsī—
    #14

Share This Page