Exhaust flange tight - pipe loose

Discussion in 'Engine, Fuel and Exhaust' started by cdn-bigfoot, Jun 15, 2008.

  1. cdn-bigfoot

    cdn-bigfoot Junior Member

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    I've had increasingly bad popping on deceleration.
    At first I thought it was a lean mixture.
    A plug chop proved that likely not the cause.
    During a recent 300 mile road trip the popping became much worse. And the engine lurched slightly when cruising. At hard acceleration the exhaust sounded different than normal. When I got home I immediately checked the exhaust flange bolts for tightness. All tight. But the front pipe moved 3/8 inch inside the tight flange. After removing the pipes completely I found that the chrome end of the pipe was not affixed to the pipe. This means the flange has nothing to grab. Thus the loose pipe, and the popping.

    My question, and I think I know the answer is.....
    Is this chrome ring supposed to be tacked to the pipe with a welder?
    The other one is on good and tight.
    [​IMG]
    [​IMG]
    19. retaining ring (2)
    20. exhaust gasket (2)
    26. Exhaust manifold flange (2)
     
  2. Fisher

    Fisher Account Removed

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    Yeah it should be attached firmly.It's in a spot where a couple of tack/spot welds by your local welder won't show and will be far cheaper than new pipes.Unless of course you want a new exhaust system.:D
     
  3. cdn-bigfoot

    cdn-bigfoot Junior Member

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    Had my local welder tack each pipe in 3 spots with the MIG.
    Only one pipe end had come loose. I had him do the other one to be sure.
    I cleaned up the small welds with a Dremmel. Installed the pipes with new gaskets. Went for a ride. Everything is right in my world.
    :bigsmiley10:
     
  4. Fisher

    Fisher Account Removed

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    Cool.Ain't it great when the fix is easy and cheap.
     
  5. glider

    glider Veteran Member

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    Even better when the fix it period! :D
     
  6. toanjo

    toanjo Member

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    Interesting. Are these the stock pipes on your 06 Street Bob? Wouldnt this be a defect in the pipes? For what its worth, I jut changed my pipes out on my 06 street bob and had a dickens of a time getting the o2 sensor out on the rear header. It looks like the factory didnt use any anti seize on the threads and I mangled it getting it out. I wonder if they had quality problems on street bob exhaust systems in 06?
     
  7. cdn-bigfoot

    cdn-bigfoot Junior Member

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    Sorry I guess I didn't mention the brand.

    Cobra Pipes Speedster Shorts.
    And yes it was a factory defect.
    Fixed by removing them myself and getting a friend to weld the ring back on.

    Even the Cobra pipes have an awkward access to rear O2 sensor. They could have easily been made better by changing the position of sensor by 1/2 inch.

    [​IMG]