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TECHNICAL MOTOBRICK WRENCHING In Remembrance of Inge K. => The Motobrick Workshop => Topic started by: TommyT on October 14, 2019, 09:24:16 AM
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I had an exhaust stud come out of the head, it just unscrewed when removing the nut. I got out the nut off, so now do I just screw the stud back in, or add some locktite or copper antiseize? Is their a torque value I should use tightening it into the head?
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1. Apply copper anti-seize
2. Screw it back in
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Use the anti seize for the nut, then next time the stud hopefully remains in. The torque should be the same as the nut, maybe give it a bit more.
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The torque should be the same as the nut, maybe give it a bit more.
Exhaust manifold studs should not be torqued during insertion. The purpose of applying torque to a nut is to stretch the shaft of the stud thereby creating sufficient tension to hold the stud, the part and the nut in position. Torque applied to the stud during insertion could compress it, deforming it or the hole.
Backing out a stud during attempts at removal of a nut is not rare and re-installation is no big deal if threads haven't been damaged.
- Clean the threads of both the hole and the stud.
- Clean out the hole.
- Screw the stud into the hole until it just touches bottom then stop.
- If the stud has a shoulder, screw the stud into the hole until its shoulder just engages with the hole's opening then stop.
Using clean technique should be sufficient for good result.
Apply a spare amount of anti-seize to the portion of stud that the nut will travel down to the flange. Torque table values are given for clean, dry threads. When lubricant like anti-seize is applied, recommended values are approximately 10% less to prevent over-tightening. I doubt that factoid is in the forefront of many wrenchers thinking and yet, the motos keep rolling down the line—well, many of them anyway, some of those that haven't been deformed during remodeling certainly. :-)