Leaking exhaust threads

Engines, Exhaust and Fuel Systems

  1. 88_AHB

    88_AHB Well-Known Member

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    Hey everyone,
    Wondering if any of you have come across this issue.I recently fired up my rebuilt 318 and the front and rear exhaust (header) bolts were leaking coolant from around the threads? I wasn't aware that dodge runs these into the water jackets? I'm gonna pull all 4 or 8 bolts out tomorrow and either use thread sealant or rtv. Is this a common occurrence or is there something wrong?This is my first dodge,i've have been a GM for a long time and never had this issue with them.
     
  2. 7T8 Custom

    7T8 Custom Well-Known Member

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    Yes, those bolts run into the water jacket. Normally you use a stud for those holes.
     
  3. 88_AHB

    88_AHB Well-Known Member

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    Is this for the very outer corners (4) or all 8?
     
  4. 7T8 Custom

    7T8 Custom Well-Known Member

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    Just the outer 4 corners.
     
  5. SixBanger

    SixBanger Well-Known Member

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    Last edited: Jun 2, 2019
  6. Aspen500

    Aspen500 Well-Known Member

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  7. 88_AHB

    88_AHB Well-Known Member

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    Thanks everyone, never have seen something like this happen. I’ll give it a go later today.
     
  8. AJ/FormS

    AJ/FormS Well-Known Member

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    Be careful to not overtorque those fasteners. If they break, after they are locked in there, you'll be extremely irate at all the trouble that mistake is gonna cause.
    If I have to remove those corner studs to install the headers, I always put the studs back in there, with no sealer. I double-nut the buggers, torque them in there against their shoulders,and remove the nuts.Then I put a drop or two of thread locker on the shoulder right next to the head and let it wick in. Finally, I use the slanty conical washers and usually brass nuts. I doubt anyone could ever overtighten those brass nuts to break the studs,lol.
    On one occasion I slotted the rearmost holes down thru the flanges, because I was afraid getting the studs out would be impossible without breaking them. Those special slanty washers came to the rescue, and bridged the slots.
    Some say those brass nuts come loose by themselves.
    I say; get a better gasket.
    The gaskets that came with my TTIs were fabulous. Nothing ever came loose. After about 5 or 6 reuses, they finally wore out. I cannot recall what brand I replaced them with, but they must be good,cuz they've been on my 367 since 2004,IIRC. I remember I got them from Jegs, not house-brand tho.
     
  9. 88_AHB

    88_AHB Well-Known Member

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    Curious what’s the advantage or disadvantages of using a stud vs bolt for the 4 corners?
     
  10. volare 77

    volare 77 Well-Known Member

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    The stud seals better against antifreeze leakage than a bolt because of the shoulder. If the stud makes it hard to install the headers then either cut them a little shorter or leave them out until you get the header in place. I like the studs because it helps with keeping the gasket in place when installing headers and a place to hang the headers while trying to install the rest of the bolts. The problem with stock heads is many times the studs are rusted in place and can be a bear to get out without damage.
     
    Last edited: Jun 4, 2019
  11. Oldiron440

    Oldiron440 Well-Known Member

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    On my big blocks I've been able to retain all the studs with the exception of two on each side do to length and interference with the headers. I much prefer the studs over bolts.
     
  12. 88_AHB

    88_AHB Well-Known Member

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    I put all bolts in and used the high temp sealant. No leaks so far... Perhaps I should switch out for studs instead now to make sure I’m good for later.
     
  13. volare 77

    volare 77 Well-Known Member

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    Only the four end holes on a small block have coolant. As long as the bolts don`t loosen you should be ok.
     
  14. 88_AHB

    88_AHB Well-Known Member

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    I know this now, just meant i'm second guessing on those 4 with bolts in instead of studs lol!