Help with a head/header bolt thread hole
Thread Starter
Racer
Joined: Nov 2010
Posts: 397
Likes: 33
From: Campton Hills, Illinois
Help with a head/header bolt thread hole
I was just reinstalling the passenger side header bolts on my 02 Z06 tonight. All the bolts ran in with my fingers except one. You can see it is going in at a angle after about 1-2 rotations. I tryed cleaning out the internal threads but no help. I ran a nail inside the threads and can feel a "bump" on the top of the threads about 3 threads in, it's only on the upper part of the thread hole. I installed these header just 2 months ago and do not recall any problems then.
My question is can I correct this w/o removing the head? I could just continue to run it/force it in. The next time the headers come off it would be to have the heads reworked anyways and I could address the problem then.
It is the 3rd bolt hole from the front of the car. Headers are LG streets.
My question is can I correct this w/o removing the head? I could just continue to run it/force it in. The next time the headers come off it would be to have the heads reworked anyways and I could address the problem then.
It is the 3rd bolt hole from the front of the car. Headers are LG streets.
Thread Starter
Racer
Joined: Nov 2010
Posts: 397
Likes: 33
From: Campton Hills, Illinois
tap
I was thinking of that regardless of the fact some people advise against it becuase they feel it removes material. I need to fin out hte thread and pitch for the tap first .
Tech Contributor
Joined: Dec 1999
Posts: 32,910
Likes: 2,402
From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
If it were me,,,,, I would fix it now!!
Remove the header (position it to gain access to the damaged bolt hole) Use a small metal pick and see if you can clean up the misaligned thread. You can then start the a good bolt with ample antiseize in the hole straight and screw it in as far as it will go by hand. "LIGHTLY" Tap the head of the bolt with a small hammer while appling light clock wise rotation and see if you can move the bolt a little further. If it wont screw in after you tap it a couple times STOP! Sometimes this will fix the issue without a clean out tap and sometimes it wont.
If that fails,, use a PURPOSE BUILT Thread cleaning tap. It will clean the threads without removing excessive material.
BC
Remove the header (position it to gain access to the damaged bolt hole) Use a small metal pick and see if you can clean up the misaligned thread. You can then start the a good bolt with ample antiseize in the hole straight and screw it in as far as it will go by hand. "LIGHTLY" Tap the head of the bolt with a small hammer while appling light clock wise rotation and see if you can move the bolt a little further. If it wont screw in after you tap it a couple times STOP! Sometimes this will fix the issue without a clean out tap and sometimes it wont.
If that fails,, use a PURPOSE BUILT Thread cleaning tap. It will clean the threads without removing excessive material.
BC
Thread Starter
Racer
Joined: Nov 2010
Posts: 397
Likes: 33
From: Campton Hills, Illinois
tap
Well I could not find a metal scraping tool or a clean out tool at autozone or home depot so I tried a 8x1.25 tap. I first used it in a good internal thread just to see how it felt. I only screwed it in a few rotations. I then tried it on the bunged up thread and it started getting tight so i worked it some by going clockwise then counter clockwise. I started getting nervous because it felt like it could get stuck in there so after a couple attempts I stopped. It does seem like the tap is getting chewed up some at the end. The thread thats causing problems is about 3 or 4 threads in and on top.
I might try napa to see what they have. I know I've seem a tool that has a screwdriver like handle and the shaft swivels and the tip has a somewhat bend in it and if I remember correctly has a sharpe edge on it.
Is this something I should try using?
I might try napa to see what they have. I know I've seem a tool that has a screwdriver like handle and the shaft swivels and the tip has a somewhat bend in it and if I remember correctly has a sharpe edge on it.
Is this something I should try using?
Tech Contributor
Joined: Jan 2007
Posts: 19,449
Likes: 1,155
From: Dyer, IN
Based on your description, that tool is used to clean up burrs on a through hole, not to clean up threads on a blind hole. I have a hard time believing the tap is getting chewed up. Hopefully, you are using a lubricant when using the tap. It may take some time to clean up that burr in the hole.. Not forcing, and using the clockwise/counterclockwise approach should work. Can you see the obstruction with an inspection mirror?
Le Mans Master
Joined: Jan 2001
Posts: 5,008
Likes: 508
From: Hilton NY
You need a bottoming tap to clean up all the threads, a regular tap is tapered too much. Here's a link to buy one, http://www.mcmaster.com/#standard-taps/=iejjh8
Thread Starter
Racer
Joined: Nov 2010
Posts: 397
Likes: 33
From: Campton Hills, Illinois
lubricant
I probably was not using enough lubricant as I was only using a spray on dry lubricant. I'll try motor oil? and keep working it as suggested.
it was gettingprety dared tight before.
it was gettingprety dared tight before.
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Thread Starter
Racer
Joined: Nov 2010
Posts: 397
Likes: 33
From: Campton Hills, Illinois
fixed
Ok, Took the advise although I stuck with the tapered tap because thats what I had. I used motor oil as a lubricant and went in .25 revolutions and then backed out the same then went forward again. Took about 15-20 minutes. Although the bolt does not go in as easy as the others it does not take much effort with a socket and rachet to bring it up to were it needs to be.
I appreciate the help and the quick responses.
Reattaching the headers was basically the last thing I had to do after replacing the clutch by myself on jackstands. You can imagine my reaction when I ran into a road block with a little bolt after all the work I had done lol.
I did make up a pretty cool jack stand setup for use with steel jacking pucks that I'll share later for anyone interested.
I appreciate the help and the quick responses.
Reattaching the headers was basically the last thing I had to do after replacing the clutch by myself on jackstands. You can imagine my reaction when I ran into a road block with a little bolt after all the work I had done lol.
I did make up a pretty cool jack stand setup for use with steel jacking pucks that I'll share later for anyone interested.
Le Mans Master
Joined: Mar 2011
Posts: 6,835
Likes: 302
From: Columbia SC
A tapered tap would be best for your situation. It will more slowly remove the bad area. A bottom tap is for getting threads cleaned at the bottom of the hole. If you can install a stud into this hole and still remove the header, I would do that so that you are not threading in a bolt each time in the future. If you need to cut the stud so it is just long enough to put a nut on it could help with exhaust removal room.
Team Owner
Joined: May 2001
Posts: 87,357
Likes: 1,592
From: Western NY
You need a bottoming tap to clean up all the threads, a regular tap is tapered too much. Here's a link to buy one, http://www.mcmaster.com/#standard-taps/=iejjh8