Detroit 12.7 Exhaust manifold removal??

Discussion in 'Heavy Duty Diesel Truck Mechanics Forum' started by Green461, May 23, 2024.

  1. Green461

    Green461 Light Load Member

    137
    83
    Mar 22, 2019
    Southern WI
    0
    This has about 900k miles on since overhaul so Im guessing its been on since then.

    Do these manifold bolts tend to break? Usually I heat manifold bolts with torch and never break them.. but i have not done this type before... has long spacer and long bolt, making the ability to heat it with a torch and actually affect the threads way harder.
    Would it be easier to use a cut off wheel and cut all the heads off, remove manifold, then i can easily get to the base of the bold and heat it and remove them with a pipe wrench?
    I just want to avoid them breaking off flush or having to use a drill.
     
  2. Truckers Report Jobs

    Trucking Jobs in 30 seconds

    Every month 400 people find a job with the help of TruckersReport.

  3. blairandgretchen

    blairandgretchen Road Train Member

    12,284
    62,390
    Dec 9, 2011
    South west Missouri
    0
    I’d use a torque wrench set to 20% higher than the bolt spec, and see if they budge first.

    Apply some heat to bolts and try again if no budge.
     
  4. Big Road Skateboard

    Big Road Skateboard Road Train Member

    4,693
    22,444
    May 2, 2021
    0
    I've seen maybe 1 or 2 exh manifold bolts broken on a 60 in almost 30 years workin on em. Not really an issue.

    None of those were broken during removal, and i've removed hundreds.

    As long as you can get on them solid, a 1/2" impact and a 17mm socket

    BTW, they are prone to crack behind the turbo flange.
     
    Last edited: May 23, 2024
  5. jamespmack

    jamespmack Road Train Member

    19,282
    208,550
    Mar 25, 2014
    OH
    0

    I can't recall ever extracting one from a series 60 either. Cat yes, N14 was normal rust issues.


    Hammer on the head with a 3/4lbs hammer then hit with impact.
     
    Last edited: May 23, 2024
    Reason for edit: Hammer, not hair. Lord this phone trys to make me look worse than I am.
  6. Green461

    Green461 Light Load Member

    137
    83
    Mar 22, 2019
    Southern WI
    0
    Thanks all.. sounds relieving..
     
    Bean Jr. Thanks this.
  7. Smellfunny

    Smellfunny Road Train Member

    1,440
    960
    Jan 28, 2012
    South Carolina
    0
    I have only seen maybe 1 out of thousands broke on a Series 60. ISX is the worst for broken studs.
     
    little cat 500 Thanks this.
  8. Green461

    Green461 Light Load Member

    137
    83
    Mar 22, 2019
    Southern WI
    0
    Wow, I was expecting a fight, easiest thing ever to come off. Manifold looks perfect, it rings so no cracks.. however the slip joints leak like mad. Do they make a seal for them? Be nice to machine grooves in and put a couple gapless piston rings in it..
     
  9. Big Road Skateboard

    Big Road Skateboard Road Train Member

    4,693
    22,444
    May 2, 2021
    0
    They make a seal kit. It's ridiculous priced and ineffective, and may not even fit depending on manifold setup. A new factory or normal aftermarket one will also likely leak there, cause they just aren't made well.

    I went with Full Tilt after trying both other options.

    Money well spent
     
  10. Green461

    Green461 Light Load Member

    137
    83
    Mar 22, 2019
    Southern WI
    0
    $500 for a manifold, something with no moving parts is crazy... I cant even fathom the price of the full tilts. And besides not leaking there is no other benefit to it. They say there is, but its a pipe directing exhaust to the turbo which is the choke point, the turbo is, not the manifold., so not sure what they are smoking. Of course everyone that puts one on sees an improvement... because their old one was leaking lol..

    I found some 2.5" bore cast iron piston rings on ebay , 4 for $16. The ends overlap so its a total seal type ring. I will cut some grooves in each pipe, put 2 rings on each joint. use ring compressor to install pipes together. I dont know why they were not like this to begin with. It will be impossible to blow out or leak.
     
  11. Big Road Skateboard

    Big Road Skateboard Road Train Member

    4,693
    22,444
    May 2, 2021
    0
    I get it. Everybody is different. I don't want to tinker, I want it fixed, RFN, and I don't want to worry about it again.

    I've got to much to do to eff around with it
     
  • Truckers Report Jobs

    Trucking Jobs in 30 seconds

    Every month 400 people find a job with the help of TruckersReport.