Possible cracked head

Discussion in '6.9L IH & 7.3L IDI Diesels' started by Alwaysreadyrob, Dec 4, 2017.

  1. G. Mann

    G. Mann Full Access Member

    Posts:
    832
    Likes Received:
    9
    Joined:
    Apr 13, 2007
    Location:
    Phoenix, AZ
    Radiator pressure test will only test if the cooling system will hold pressure. You are losing coolant... quite a lot.. From your description, it has all the hallmarks of blown head gasket... Start the truck, pull off the radiator cap, and watch what happens. If the coolant surges in the radiator and makes bubbles, you have compression gasses coming into the cooling system... at about 300 psi... radiator cap is 16 psi.. or 13 psi.. in operation, the combustion pressure will push coolant past the cap.. out the overflow tank.. and the fan will blow it as a mist, so you don't see it... soon as enough coolant is missing, you overheat...

    Simple test, just run engine with cap off and watch..
     
    Alwaysreadyrob and 79jasper like this.
  2. Alwaysreadyrob

    Alwaysreadyrob IDI TURBO

    Posts:
    102
    Likes Received:
    8
    Joined:
    Aug 31, 2012
    Location:
    Loma Linda CA
    Very detailed description, thank you... i will do this today .
    How long until i should start seing the signs ?
    5 min - 15 min
     
  3. G. Mann

    G. Mann Full Access Member

    Posts:
    832
    Likes Received:
    9
    Joined:
    Apr 13, 2007
    Location:
    Phoenix, AZ
    Depends on how big the leak is, if a section the the head gasket is blown out and you have two cylinders pumping gasses into the cooling system.. it will show up right away.
    If it's a "little leak" it may take until you get the engine warmed up a little... or to full operation temp... again, depends on size of the combustion leak...

    I have a 92 / 7.3 with a turbo that I bought that has a "really blown" gasket.. the radiator starts to surge and bubble as soon as it's started... and it also blows coolant out the exhaust at white steam... yours doesn't sound as bad... yet..
     
    Alwaysreadyrob likes this.
  4. Alwaysreadyrob

    Alwaysreadyrob IDI TURBO

    Posts:
    102
    Likes Received:
    8
    Joined:
    Aug 31, 2012
    Location:
    Loma Linda CA
    No im blowing white steam now too. How much should i be prepared to pay a shop the fix it ? Depends huh.... if just head gasket or cracked head huh
     
  5. Hydro-idi

    Hydro-idi Full Access Member

    Posts:
    2,025
    Likes Received:
    160
    Joined:
    Nov 8, 2011
    Location:
    Lodi, California
    I would forget about the tests if your blowing white steam out the exhaust. That’s enough of an indicator to know somethings wrong.
    You need to get it fixed and you won’t know exactly what’s going on until you tear into the engine.
    Plan on a bill of at least 3k to have a shop do it. That will include replacing headgaskets and getting heads checked for cracks & rebuilt.
    I would recommend doing it yourself. You’ll save yourself lots of $ by going that route. I’ve done this job multiple times in frame and it’s not all that bad if you have a cherry picker to lift heads off.
    It just takes time, patience, and lots of organization with the parts you take off & put back on.
     
    Alwaysreadyrob and Thewespaul like this.
  6. Alwaysreadyrob

    Alwaysreadyrob IDI TURBO

    Posts:
    102
    Likes Received:
    8
    Joined:
    Aug 31, 2012
    Location:
    Loma Linda CA
    The pressure in the coolant test held at 14PSI for 4 minutes .
    What about using the bars stop leak in a bottle ?

    864AA26B-EB81-4C93-8139-E01F455DACEF.jpeg
     
  7. 79jasper

    79jasper Chickenhawk

    Age:
    25
    Posts:
    14,011
    Likes Received:
    446
    Joined:
    Oct 13, 2012
    Location:
    Collinsville, Oklahoma
    Depends, do you want it fixed? Or make things worse?

    Sent from my SM-G892A using Tapatalk
     
    Alwaysreadyrob likes this.
  8. Alwaysreadyrob

    Alwaysreadyrob IDI TURBO

    Posts:
    102
    Likes Received:
    8
    Joined:
    Aug 31, 2012
    Location:
    Loma Linda CA
    Video if i can upload it .fixed right
     
  9. 79jasper

    79jasper Chickenhawk

    Age:
    25
    Posts:
    14,011
    Likes Received:
    446
    Joined:
    Oct 13, 2012
    Location:
    Collinsville, Oklahoma
    Then no, no stop leak.

    Sent from my SM-G892A using Tapatalk
     
    jrollf likes this.
  10. Sidewinded_idi

    Sidewinded_idi Full Access Member

    Posts:
    610
    Likes Received:
    203
    Joined:
    May 20, 2017
    Location:
    Yucaipa ca
    Idk I’ve had some pretty good luck with eggs in the radiator!!!
     
  11. G. Mann

    G. Mann Full Access Member

    Posts:
    832
    Likes Received:
    9
    Joined:
    Apr 13, 2007
    Location:
    Phoenix, AZ
    If I understand your earlier post, you have white smoke out the exhaust [steam].. that tells me it's NOT a leaking radiator issue.. but a head gasket or cracked head issue...

    If you add radiator seal.... it will goop up your radiator and speed up the overheat problem... but do nothing to cure the real problem...

    Your truck....your call... good luck
     
    Alwaysreadyrob and Thewespaul like this.

Share This Page