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General => Technical | How To => Topic started by: TBR125 on April 06, 2020, 03:45:17 PM

Title: Stripped Exhaust Stud Help
Post by: TBR125 on April 06, 2020, 03:45:17 PM

My exhaust stud pulled out from the head on my agility under spec torque.

Any cheap repair options? I know my head is cheap but would prefer not to change that.

Title: Re: Stripped Exhaust Stud Help
Post by: Stig / Major Tom on April 06, 2020, 03:58:27 PM

Same thing happened to a LIKE200i owner in Austria - "torque wrench"
He has a thread here, somewhere, think he had to finally send it to a shop for drilling and coil if memory serves.

You're an experienced scooter wrencher - I'm surprised you used a torque wrench on such a small fitting?
Torque wrenches are so very rarely recalibrated for accuracy - critical on small ones.
Stig

Title: Re: Stripped Exhaust Stud Help
Post by: TBR125 on April 06, 2020, 05:12:37 PM

I invested in a 1/4 inch precision spring dial wrench. I have found proper torque and a locking mechanism to be a crucial part of maintenance after a variator nut flew the coop.

I drilled and tapped the head for a larger bolt then used a die to re-cut the protruding bolt to M8-1.25. Time consuming but free.

Title: Re: Stripped Exhaust Stud Help
Post by: CROSSBOLT on April 06, 2020, 06:45:24 PM

All primed to brag an Helicoil wannabee thread insert but you already nailed it!

Title: Re: Stripped Exhaust Stud Help
Post by: TBR125 on April 06, 2020, 10:30:23 PM

I drilled and tapped the center of a bolt to thread the stud into. The first one was drilled off-center because i'm using a cordless drill with an inaccurate chuck. The second one should be good when I finish it.

Title: Re: Stripped Exhaust Stud Help
Post by: TBR125 on April 06, 2020, 10:31:27 PM

I need a vise.

Title: Re: Stripped Exhaust Stud Help
Post by: TBR125 on April 06, 2020, 10:32:23 PM

Picture.

Title: Re: Stripped Exhaust Stud Help
Post by: Iahawk on April 12, 2020, 03:08:00 PM

that is some damn impressive, precision drilling!

Title: Re: Stripped Exhaust Stud Help
Post by: TBR125 on April 12, 2020, 05:27:42 PM

Thanks, I'm to thrifty to buy a Helicoil. Besides, a Grade 8 insert precision cut from billet steel must be superior:)

Title: Re: Stripped Exhaust Stud Help
Post by: Tromper on April 13, 2020, 05:18:13 AM

Nicely done.
I've seen worse done with a press.

Title: Re: Stripped Exhaust Stud Help
Post by: TBR125 on April 14, 2020, 04:14:26 AM

Thanks Tromper, I need a press.