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-   -   How do you break small crusty bolts free? (https://www.rx7club.com/1st-generation-specific-1979-1985-18/how-do-you-break-small-crusty-bolts-free-990961/)

Redliner223 03-12-12 05:46 PM

How do you break small crusty bolts free?
 
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I've been running into this problem all over the car. All of the large bolts aren't a problem but the small corroded and crusty bolts are getting stripped. What's the easiest way of breaking them free?
I've been using liquid wrench and it works wonders on the larger stuff but when it comes to these little guys they stop me dead in my tracks.

DivinDriver 03-12-12 05:54 PM

I hit them with a few drops of PB Blaster, let them sit for a while so it can wick inside, then freeze it down to about -35 using an upside down can of dusting spray to gently 'wet' them down. Works wonders!

Redliner223 03-12-12 06:18 PM

Hmmm actually shrinking the bolts. That's a really good idea.
How long do you spray it with the can of air?

rx71king 03-12-12 06:34 PM

10mm Flare Nut Wrench.............http://www.ebay.com/itm/K-Tool-44910..._Tools&vxp=mtr

Redliner223 03-12-12 09:06 PM

I know the size and tools aren't the problem trust me.
If you look at the picture one of the corners has been rounded off and a 10mm wrench did that.
The system if old (also original) so there is all of this gunk in there corroding and adding crap on the threads making the connections hard as a rock.
Today I was trying to replace the clutch hose and ran into this problem and I didn't want to round off all of the corners.

mazdaverx713b 03-12-12 09:15 PM

heat the area surrounding the bolt with a map gas torch. unless of course the bolts are on the interior or near a surface that will not enjoy the heat. i've used heat on the clutch hose's metal fitting. it will take it for a short time. you will need a flare wrench for the steel line's fitting.

rx71king 03-12-12 09:17 PM

the flare nut wrench will not let u round the corners....you will f@#k it up with a regular 10mm wrench........

DivinDriver 03-12-12 09:51 PM


Originally Posted by Redliner223 (Post 11014675)
Hmmm actually shrinking the bolts. That's a really good idea.
How long do you spray it with the can of air?

Maybe 15, 20 seconds, till it's boiling the penetrating oil out & frosting up good.

Heat works too, as does the two in careful combination - - just don't spray the freeze spray into the flame! Heat it, shut off the torch, then chill it. Thermal shock for the win.




Originally Posted by rx71king (Post 11014927)
the flare nut wrench will not let u round the corners....you will f@#k it up with a regular 10mm wrench........

This is true, too; flare wrench supports the fitting all the way around, instead of just two sides. Never use anything else on a flare fitting.

Redliner223 03-12-12 10:27 PM

No, the 10mm wrench did round off the corner but our flare nut french too didn't help.
Just using the wrenches, they just started bringing the hard line down along with the bracket attached to the fire wall.
I'm going to try the heat method tomorrow, but what ever is stopping me is pretty dang strong.

IanS 03-12-12 10:35 PM

If you notice on the opposite side of the bracket there is another 6 sided part that you can hold with another wrench so the bracket does not bend. When in doubt, motherfuckin' vice grips. Every time, makes it happen.

rx71king 03-12-12 11:07 PM

:)^

Sgt.Stinkfist 03-12-12 11:08 PM

when heating hydraulic fittings, dont go too balls deep with the torch, and occasionally quench the fitting on the rubber hose end. You dont wanna cook the rubber and teflon out of the hose, otherwise itlll blow out or clog up

B_w_S 03-12-12 11:11 PM

I always have PB blast on hand. I find cussing a lot at it usually helps too.

Jeff20B 03-13-12 02:07 AM

A vice grip sometimes is the only way, when a 10mm flare fails and you can't use heat.

Divin, the idea of using canned air sounds good.

Sgt.Stinkfist 03-13-12 03:34 AM

^ as an in between, from experience, before vice grip and after 10mm flare wrench, try a 3/8" flare wrench. a 3/8" will sometimes be just small enough to take up the gap caused by rounding or heavy oxidation/rust.

at my job i absolutely hate having to replace brake lines, especially for free, and ive found that a oxy/acetaline torch, penatrating oil and a 3/8" have saved my ass numerous times

t_g_farrell 03-13-12 08:23 AM

All good advice in here. My steps are:

1. Penetrating oil
2. Flare nut wrench
3. Heat
4. Repeat 2 & 3 until the rounding starts
5. Vice grips (always works) and a hammer

That cold spray is also sounding good DD. Also if its this hard to get off a brake line,
I usually replace the brake line while I'm there.

DivinDriver 03-13-12 09:39 AM


Originally Posted by Jeff20B (Post 11015192)
Divin, the idea of using canned air sounds good.

I've used it several times recently, and it worked like a champ.

Just yesterday, I used it to break the nuts free from the threaded studs that hold the transmission cross member to the frame; you know, the ones that always unscrew out of the frame because the nuts are usually rusted solid to the studs?

Locked the studs' smooth parts in the vice and gave em the PB Blaster. An hour of soaking later they still wouldn't turn - - would rotate in the vice jaws instead.

20 seconds' worth of the cold juice on the junction between the stud and the nut, and they came free easily with a little hammer encouragement on the wrench.

Jeff20B 03-13-12 12:45 PM

You know it's funny. I've read more times when PB blaster failed than when it actually worked on this forum. As such, I've never bought any. Does it work or is it hype?

I use WD-40 or Valvoline's 1-2-99. And of course heat from propane or MAPP gas.

83Limited 03-13-12 02:13 PM


Originally Posted by Redliner223 (Post 11015016)
No, the 10mm wrench did round off the corner but our flare nut french too didn't help.
Just using the wrenches, they just started bringing the hard line down along with the bracket attached to the fire wall.
I'm going to try the heat method tomorrow, but what ever is stopping me is pretty dang strong.

Another trick that works with corroded fasteners sometimes is try to tighten it...occasionally it will free up and you will be able to remove it. Usually works for me when combined with some type of penetrating oil....

Redliner223 03-13-12 02:29 PM


Originally Posted by Jeff20B (Post 11015579)
You know it's funny. I've read more times when PB blaster failed than when it actually worked on this forum. As such, I've never bought any. Does it work or is it hype?

I use WD-40 or Valvoline's 1-2-99. And of course heat from propane or MAPP gas.

PB Blaster, Liquid wrench, WD-40, they all work they just need some time to eat away at the rust and corrosion.

None of these has failed me until now.
WD-40 is my personal favorite but all I have on hand is the liquid wrench for now.

DivinDriver 03-13-12 02:32 PM


Originally Posted by Jeff20B (Post 11015579)
You know it's funny. I've read more times when PB blaster failed than when it actually worked on this forum. As such, I've never bought any. Does it work or is it hype?

It seems to work fairly well if you can give it time to actually penetrate the corroded junction. Case in point was removing my (1980 original) Pitman arm recently.

I had the steering box off the car and in a bench vise, and got the nut off without too much trouble... but the arm refused to come off even when beating on a 2-ft bar with a 3 lb hammer. Vise was starting to pull out of its mounting, and I was afraid of shock damage to the sector shaft teeth if I used more force.

I shot the junction between the arm and the shaft with PB (just enough to wet and wick it), and let it sit 24 hours.

Next day, with no more than a firm grunt on the bar, the puller slid that sucker off slick as you please.

It's not miraculous but it does seem to work well at breaking down corrosion & getting between pressure-fit parts.

BUMBLEBEE7 03-13-12 05:10 PM

Spray Kroil on it!

orion84gsl 03-13-12 08:38 PM

I don't. I give er til they break, curse like the trucker I am then spend hours fixing the problem I created. The good thing is most of the important, prone to corrosion bolts on my car are new at this point. Broke one of the two that holds the trans crossmember to the transmission, finally bought a tap and die kit to fix that mess. Bolt extractors suck, just use a cobalt bit and drill the sucker. In your case, plan to replace both the hard line and the rubber line. Just torch the sucker (shield the area around it unless you like the look of burned paint). Get it hot, let it cool then try it. A slight tightening sometimes helps to break it free, but half the time I just end up breaking them that way too.

82FanTC 03-13-12 10:08 PM

when using penetrating oil of any kind make sure to tap the bolt/nut with something to work the oil in.

Heat always seems to work the best. The old school farm trick is to use a candle and rub the wax all over the bolt and then apply heat to the nut. Heat will draw the wax toward it, thus into the threads and hopefully help to break loose :nod:

Jeff20B 03-14-12 01:24 PM

I was looking forward to using the canned air trick. But I was successfully able to get the stud out with the double nut method. Didn't even need heat. :(

For those wondering, it's the short 10mm x 1.5 stud at the bottom of R5 and 3B front plates. I use this stud in aluminum on aluminum waterpump setups. The stud is usually difficult to remove. Not this time.


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