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Discussion Starter · #1 ·
Hi Everyone, Need some advice. My new sliders are on the way and I have read that I need to clean up the threads on the frame mounting holes. My FJ is an 07 and the holes do have some rust and grit. I tried some Kroil to break up the rust followed by running a .30 cal brass brush through them. The process helps a little, but I am afraid to thread the 8 x 1.25 bolt I purchased to help clean them out in too far. I plan to buy a good quality 8 x 1.25 thread chasing tap. Do I need to use any special lubricant with the tap to help it clean things out or do I just run it through dry?
Thanks in advance.
 

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It is something you could easily over think. I agree any oil is better than dry. That said just quickly looking at an easy place to get to Lowes has dark cutting oil for next to nothing in cost. Yes you can buy better like Tap Magic or Anchorlube but you are just cleaning threads not making threads. Your right a tap is smarter than a bolt.
 

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Hi Everyone, Need some advice. My new sliders are on the way and I have read that I need to clean up the threads on the frame mounting holes. My FJ is an 07 and the holes do have some rust and grit. I tried some Kroil to break up the rust followed by running a .30 cal brass brush through them. The process helps a little, but I am afraid to thread the 8 x 1.25 bolt I purchased to help clean them out in too far. I plan to buy a good quality 8 x 1.25 thread chasing tap. Do I need to use any special lubricant with the tap to help it clean things out or do I just run it through dry?
Thanks in advance.
A .30 cal bore brush is a little undersize for an 8mm thread, a 9mm/.35 cal brush will scrub better if you chuck in a drill, as having the brush rotate into the thread root where the debris is will be far more effective than just pushing it straight through. Just about any light lubricant will work fine ... motor oil, WD-40, ATF, etc. As previously stated, you do not want to be cutting new threads, you are just cleaning debris and corrosion out of the existing threads.

You aren't going to find a 'thread-chasing' tap, you just want a conventional metric straight-thread tap. Of the three commonly available tap styles (taper, plug, and bottoming), the preferred style is a taper tap that has the longest tapered lead-in at the end, this should make it easiest to pick up the existing thread start and minimize the danger of cross-threading. If you can't find a taper tap, a plug tap is almost as easy to start. You do not want a bottoming tap.

After finding the thread start, turn the tap about 2 turns, then back it out 1/2 turn, add more lube, then forward again. If there is a lot of debris or corrosion in the threads, remove the tap and clean off the debris after every few turns.

The holes that will be most difficult to work with are the two most forward holes. The frame rail blocks access, so there is no clearance for a tap handle. You'll have to start the tap using your fingers, and then turn it using a small open-end wrench. Be very careful not to side-load the tap and break it off.

I'd spend the extra $ to get a name-brand American made tap, and not a cheap imported tap from Amazon, etc. The cheap imported tape are frequently improperly heat treated (hard but extremely brittle) and will break easily, which will be a nightmare to remove.
 

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And another suggestion.....

I had a heckuva time using the handle that was supplied in my kit.... I got the following ratcheting handle. I've only used it once now, but it seemed to work nicely.
Sword Nickel Metal Fashion accessory Dagger
 

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x2, x1000, definitely run a tap through any threads which have been sitting, exposed to the elements for any period of time, before trying to put a bolt in.

Turn it in a little bit, until you start to feel some resistance and then back it out, and then in again, and repeat. Once you get the feel for it you can become more efficient, but the main thing to keep in mind is: the crud that gets cleaned off has to go somewhere, and the flutes in the sides of the tap can only hold so much, so you want to keep them clean so the tap keeps going in without jamming. A tap is made of a very hard, very brittle material and they can snap when mishandled by jamming tight, halfway in a hole by not cleaning out the swarf.


N
 

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when I installed my sliders, I just made my own thread chaser. Got a bolt (obviously the same size and pitch as the threads), got my Dremel and cut a few grooves down the side and then ground down the sides of the tip a bit to get everything started. Easy and worked like a charm!
 

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A .30 cal bore brush is a little undersize for an 8mm thread, a 9mm/.35 cal brush will scrub better if you chuck in a drill, as having the brush rotate into the thread root where the debris is will be far more effective than just pushing it straight through. Just about any light lubricant will work fine ... motor oil, WD-40, ATF, etc. As previously stated, you do not want to be cutting new threads, you are just cleaning debris and corrosion out of the existing threads.

You aren't going to find a 'thread-chasing' tap, you just want a conventional metric straight-thread tap. Of the three commonly available tap styles (taper, plug, and bottoming), the preferred style is a bottoming tap that has the longest tapered lead-in at the end, this should make it easiest to pick up the existing thread start and minimize the danger of cross-threading. If you can't find a taper tap, a plug tap is almost as easy to start. You do not want a bottoming tap.

After finding the thread start, turn the tap about 2 turns, then back it out 1/2 turn, add more lube, then forward again. If there is a lot of debris or corrosion in the threads, remove the tap and clean off the debris after every few turns.

The holes that will be most difficult to work with are the two most forward holes. There is no clearance for a tap handle, so you'll have to start the tap using your fingers, and then turn it using a small open-end wrench. Be very careful not to side-load the tap and break it off.

I'd spend the extra $ to get a name-brand American made tap, and not a cheap imported tap from Amazon, etc. The cheap imported tape are frequently improperly heat treated (hard but extremely brittle) and will break easily, which will be a nightmare to remove.
As a Tool Maker of 40+ years, you give perfect advise.
And I agree with the American made tap (my go to for this type of work is a Plug tap).
 
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Discussion Starter · #10 ·

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Discussion Starter · #11 ·
Hi Guys and Ladies, Just a quick update. I really like the RCI sliders. They appear to be real heavy duty. Just a few thoughts. As I said previously, get the thread chaser. I cleaned each hole carefully and thoroughly. Use plenty of oil. I used Castrol 10w30. I had the nuts clean enough to be able to hand tighten a bolt in each one. That made it much easier for me to actually bolt up the sliders. I am 69 and 160# in pretty good shape, but they are heavy and awkward. Use jack stands and some boards. Clean the excess oil/grit out of the holes with a q-tip. RCI recommends using an anti-seize compound on the bolts. Put the Wheel Car Automotive side marker light Tire Plant
compound on all eight bolts at the same time and put them in a little cup/Tupperware.

With their sliders it is only necessary to unbolt the forward break line bracket. When you go to reinstall it, rather than trying to use the original bolt, use one of the RCI supplied bolts. RCI gives you 24 bolts and washers, but you only need 16. The original bolt is really too short to go back in, but is an 8mm also. The new bolt makes it really easy to get the bracket back in.

I also greased the back side of the sliders with Mobil 1 grease to inhibit rust.
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