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Jacket
03-17-2008, 07:55 AM
What do you guys use to clean out a bolt hole with minor rust, especially small diameter (M6 or M8)? The bolts themselves are easy once they are removed, but what "techniques" do you guys have for getting down into the hole and cleaning up the threads before re-inserting the bolt?

leiniesred
03-17-2008, 08:11 AM
a tap I guess.

Realistically, I just neverseize the bolt and stick it back in the hole.

MDH33
03-17-2008, 08:13 AM
copious amounts of PB blaster and then a tap.

RicardoJM
03-17-2008, 08:21 AM
Thats a great question and I'm interested in hearing what others do. When I am fortunate enough to get a bolt out w/out breaking it off (which is rare) I'll drop the bolt and nut into a coffe can of degreaser and let them sit for a bit. I then hit them up with a small brush (tooth brush size) to clean the threads.

If the bolt hole is "built in", I'll still clean up the bolt, and if it all looks good on the threads, I'll put some grease on the bolt and gently work it in and out a few times to clear any residue in the bolt hole till it goes smooth.

In either approach, when putting everything back together I make sure to apply a light bit of grease (or anti-sieze) to the threads so that things will come apart later.

I've also heard that some guys who know the thread pitch and size will also use an inexpensive tap to chase the threads and clear up any debris.

nuclearlemon
03-17-2008, 08:39 AM
if it's rough, than i'll run a tap through it, but if it's just surface rust, then a dab of silicone or anti seize and run the bolt in.

DaveInDenver
03-17-2008, 08:49 AM
If the bolt came out relatively clean, I just goop a new or cleaned up bolt with anti-seize and thread 'er back in.

You need to take care running a regular cutting tap into the hole (or running a die on the bolt), you lose a little material each time. The right tool to use is a thread chasing tap or die. They don't cut new threads, but just clean up old threads.

In most cases, not a huge deal, but on critical bolts you need to not remove too much material. One example is chasing head bolt threads in the block. Never use a cutting tap or you risk eventually stripping the threads in the block.

Rezarf
03-17-2008, 09:09 AM
Jacket-

I have some metric taps if you want to chase some threads, like others have said, little cutting oil, chase the thread, then a dab of anti-sieze,

I have been meticulous about adding anti-sieze to every bolt I remove, and it has been working wonders since owning my rig 9 years now.

Uncle Ben
03-17-2008, 09:19 AM
Jacket-

I have some metric taps if you want to chase some threads, like others have said, little cutting oil, chase the thread, then a dab of anti-sieze,

I have been meticulous about adding anti-sieze to every bolt I remove, and it has been working wonders since owning my rig 9 years now.


Ditto on all the above. Might even have an extra set of taps and dies you can use for a while.