# Retapping stripped threads



## vt_fish02 (Oct 16, 2009)

I have managed to strip 2 of 4 bolts that attach my front wheel hub on my lower ball joint. The bolts are M8x1.25 and I was curious if I would have to use a heli-coil insert (or similar) to fix the threads. I'm not sure since all the online videos show mechanics tapping aluminum and my hub assembly is steel. Any suggestions would be appreciated. Thanks.:headknock


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## JFolm (Apr 22, 2012)

Depending on how bad it is you could maybe clean it up with a small file. I'm not familiar with thread pitch's so that may not be realistic on your bolt.


Another thing I have used is a nut that is split in half and clamps on to your bolt. You put it on past the damaged area and back it off to clean up the threads. I'm not sure what they are called but I have used them on steel a lot.


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## vt_fish02 (Oct 16, 2009)

JFolm said:


> Depending on how bad it is you could maybe clean it up with a small file. I'm not familiar with thread pitch's so that may not be realistic on your bolt.
> 
> Another thing I have used is a nut that is split in half and clamps on to your bolt. You put it on past the damaged area and back it off to clean up the threads. I'm not sure what they are called but I have used them on steel a lot.


Thanks for the suggestions.

I forgot to mention that I stripped out the female threads for the bolts.


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## devil1824 (Sep 4, 2010)

Either heli coil or these.


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## JFolm (Apr 22, 2012)

vt_fish02 said:


> Thanks for the suggestions.
> 
> I forgot to mention that I stripped out the female threads for the bolts.


I would try a tap then. It is probably only the begging thread that you need to nudge through. Just work in a half turn then back it all the way out. Repeat. Compressed air helps to blow debris out of the hole.


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## The Last Mango (Jan 31, 2010)

That's a metric bolt if the number you posted is correct, try a thread tap first that size, if it doesn't clean up, oversize one step, and get a larger bolt , make sure you tap straigjt


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## bigstix66 (Jan 27, 2012)

1. Clean the hole with brake cleaner and blow some air to remove any trash that could clog up the tap 
2. Double check to make sure you have the right thread size then purchase a tap or tap set. O'reilly has a cheap set that will work for DIY project around the house I think it's 30-40 bucks
3. Buy some cutting fluid also for lubrication.
4. Run tap in square to the hole working back and forward in 1/4 to 1/2 turn increments 
5. Back tap out and clean hole, if tap gets tight stop and look for build up of trash dirt in the hole and on the tap clean if necessary.
6. Repeat steps 4 and 5 until complete 

The key with a tap is to have a clean hole and to make sure it starts straight. I try to use cutting fluid/oil on everything it reduces friction on the cutters and will save your tap in the long run so that 30/40 dollar set will last a good while.


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## vt_fish02 (Oct 16, 2009)

*Thanks for the suggestions*

Thanks for all the suggestions. I am no means a mechanic but seem to know just a enough to get myself in and out of trouble. I will post up on how I was able to fix this issue. The threads are metric...its a Toyota Tacoma. The only bad part is I haven't had to touch this truck for any repairs for 17 years and finally decided to replace the OEM ball joints and tie rods since I had the front wheels off from my OEM clutch replacement after 230,000 miles. Lots of rust and seized bolts from growing up in Virginia winters. Thanks again.


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## acoastalbender (Jul 16, 2011)

Since you stripped 2 threads I would look at the bolts that go into these threads and take a very close look to see if the lead-in threads are deformed which can happen as easily as throwing the bolt on the concrete garage floor. Get a 3 cornered fine file and work the first couple of threads, you can't take too much off these so don't worry about it, the threads own geometry will take over and thread into the hole regardless. BTW, if your wife has lard (Crisco) in the pantry it works as well as any hi priced cutting oil for this particular application...

.


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## bigstix66 (Jan 27, 2012)

High price cutting oil???? I picked up a can of majic tap and cutting fluid for around $4.00 at oreilly.


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## Topgun95 (May 12, 2011)

If you've stripped the threads in the hole there's not going to be enough thread engagement to hold after you run a tap through it. If so I would use one size larger bolts. With it being a 8mm bolt, you can easily tap a 3/8"-16 thread in the existing hole. The diameter of the 8mm is .314", the tap drill size for a 3/8" bolt is .316". Take a 5/16"(.3125") drill and drill out the threads and just re-tap it with a 3/8 tap. Use some form of cutting oil. Lard, etc...


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## Topgun95 (May 12, 2011)

These work great, the installation tool is a pain to use, tends to bend the stakes over before they go into the threads.


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## acoastalbender (Jul 16, 2011)

bigstix66 said:


> High price cutting oil???? I picked up a can of majic tap and cutting fluid for around $4.00 at oreilly.


A matter of opinion Rockefeller...

.


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## vt_fish02 (Oct 16, 2009)

Thanks again for all the input. I think I had the cart before the horse on this issue. I removed the two stripped bolts and the first 1/4" look like solid steel rod...no threads. My original plan was to retap but the bolts were actually M10x1.25 threads. I had purchased a tap and drill bit for this size thinking I would have to drill out the holes and rethread. I decided to just run the tap through first to see if I could clean up the internal threads. Luckily for me this worked. I was able to use the OEM bolts, which where torqued to the OEM specifications. Now, I just need a new alignment. Thanks again for all the suggestions.


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## Shooter (Jun 10, 2004)

You may be able to just drill it out and put a self locking unit on a longer bolt. It worked on my Chevy.


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## Pocketfisherman (May 30, 2005)

JFolm said:


> Depending on how bad it is you could maybe clean it up with a small file. I'm not familiar with thread pitch's so that may not be realistic on your bolt.
> 
> Another thing I have used is a nut that is split in half and clamps on to your bolt. You put it on past the damaged area and back it off to clean up the threads. I'm not sure what they are called but I have used them on steel a lot.


That is called a Thread Chaser, or a Thread Cleaner. Try that first along with running a tap of the same size and pitch through the bolt hole. You might be able to salvage it.


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