RT help. I've new exhaust nuts stuck. Any ideas?

[2001LC]

I'm pulling an aftermarket CAT some INDY shop installed a few thousands miles ago. Threads look good and clean. IDK, but nut looks OEM, but the shop buys a lot for NAPA, not Toyota unless no choice.

I pulled nuts from other side which area factory install no issues. I've pulled these nuts off a few exhaust over the years, never had any issues. Even ones old factory install. I did lube these threads with penetrating oil. They did not look like I needed lube. But I did to just condition the dry threads.

I put my Snap-on impact wrench to work on it, with beefy 12" extension and 6 pt socket. I start with 60 PSI. I notice socket barely turning and impact labored. So I cranked up PSI to >90PSI. No better. Move to next nut same thing. Grab my 3/4" breaker bar and turned some more. But all 3, are so hard to turn I fear I'll remove stud or worst break the stud. I'm very surprised stud did not already come out, of the one I have nut near off.

Anyone seen this. It will be very hard to split the nuts or drill out a busted stud. So for now I stopped.

Other CAT with new OEM nuts for comparison.

 

[katit]

No help here but 2 of 3 broke on me which was OK, but not OK since I don't think you pulling manifold..

 

[suprarx7nut]

If that were me, I'd crank the impact up to max pressure and max impact setting and rip away at it. Since I bought my Harbor freight Earthquake XT or whatever it is, I've never had a bolt I couldn't get off, provided I could reach it. Some bolts have taken 20+ seconds of sustained impact at >100 psi and full flow before they started to budge.

If you don't already have high flow fittings on all your air connections, I would prioritize that. You'll get a significant amount more flow and force compared to traditional brass/steel fittings. Night and day difference and it's probably most noticeable on an impact gun.

I've got these and a mix of home depot high flow as well: ColorFit by Milton HIGHFLOWPRO 761VC-20 Pneumatic Plugs - (V-Style, Purple) - 1/4" NPT Female, (Box of 20) - - Amazon.com

As harsh as an impact can be, I find it to commonly be the least damaging method of getting a fastener undone.

 

[nissanh]

Extensions take up good power out of your impact and make it less powerful. Stay with 6 sided hardened box socket.

 

[CanadianRockyCruiser]

Mine were completely seized when I replaced my stock exhaust with DT and EMS cat-back. I had to use angle-grinders and die-grinders to get them off. Sorry if that doesn't help.

 

[2001LC]

If that were me, I'd crank the impact up to max pressure and max impact setting and rip away at it. Since I bought my Harbor freight Earthquake XT or whatever it is, I've never had a bolt I couldn't get off, provided I could reach it. Some bolts have taken 20+ seconds of sustained impact at >100 psi and full flow before they started to budge.

If you don't already have high flow fittings on all your air connections, I would prioritize that. You'll get a significant amount more flow and force compared to traditional brass/steel fittings. Night and day difference and it's probably most noticeable on an impact gun.

I've got these and a mix of home depot high flow as well: ColorFit by Milton HIGHFLOWPRO 761VC-20 Pneumatic Plugs - (V-Style, Purple) - 1/4" NPT Female, (Box of 20) - - Amazon.com

As harsh as an impact can be, I find it to commonly be the least damaging method of getting a fastener undone.

Interesting, H. Flow 1/4" fittings. I'm due for replaces air chucks, I may give those a try. Thanks!

I used a 150, working 120PSI compressor w/ a 3/4"x 50' heavy yellow air hose with 1/2"x 25' cobra on the working end. I started with low PSI as did not feel I need more, with these, what I presumed new nuts. The went to 90 PSI didn't do any better, I was like WTF!

I've turned the nuts, that I can do. Hard to see in the poor quality picture, but one is almost off. One is turned one full turn. One is still torqued in. Keep in mind these are new and have only be on a short while.

I can crank up the pressure to 120PSI. But feel of nuts is wrong, when I tried by hand to test..

Extensions take up good power out of your impact and make it less powerful. Stay with 6 sided hardened box socket.

I'll see if I can fit a shorter extension.

Extension I used is a beefy impact one. I used the thick (beefy) extension so I'd not get any flex. It's same I used on nuts of other side. I took other side of with it no problem.

Once a felt I had and issue with these nuts using the impact. I grabbed "big boy" as I call it, my 3/4" breaker bar, it will bust any bolt on a cruiser. "Big Boy" is my best friend. I used it, just to get a better feel on what is going on. I gave enough toque to turn it, but it was very hard to turn and getting harder to turn even though nearly off. I then stopped.

It just strange 3 new nut on good threads.

I talk with shop that put these on. They say they are OEM. The non OEM they have are oval lock type, splits are OEM.

If they cross threads all three on I'll be pissed.

Soaking now.
Heat is next.

Then I'll give another shot.

Only other idea I have is split the nuts. One of the tricks I just learn in mud... Thanks guys.

 

[FxFormat]

Bolts can't seize if they're liquid

 

[AimCOtaco]

I recently removed a bunch of much worse looking OEM toyota exhaust hardware with my big impact and nothing got in my way after I stepped up to my short 1/2" extension from a longer 3/8" extension... those extensions and joints do eat lots of impact energy.
Does seem like they may be the wrong thread if they are indeed that bad to turn as nice as they look.

Either way looks like more Heat and Beat is in order.

 

[white_lx]

I've got these and a mix of home depot high flow as well: ColorFit by Milton HIGHFLOWPRO 761VC-20 Pneumatic Plugs - (V-Style, Purple) - 1/4" NPT Female, (Box of 20) - - Amazon.com

One more vote for Milton V-style couplers. Made a huge difference for me (don't forget the one on the compressor). Typically run 130 psi at the regulator and use minimum 3/8" hose ID. When the gun is impacting pressure drops to ~110psi at the gauge.

They were probably put on with an impact till they stopped turning. Reverse takes at least the same amount of torque, if not more by now.

 

[katit]

Extensions don't "eat" energy It's more of a slop/twist or lack of rigidity. Even 2 degree twist because of loose joint will cause a huge loss in useful blow. I would try longest 1/2 extension if possible.

 

[2001LC]

Well I am SO PISSED!

I want blood

No help here but 2 of 3 broke on me which was OK, but not OK since I don't think you pulling manifold..

How did you replace those studs?


Cross threaded 3 out of 7:

The SOB at Midas Muffler cross threaded 3 of 7 nut & bolts on one CAT replacement. Is his only tool and impact wrench. Oh his transgression did not stop there oh no..

I'll back up a bit. I'm pulling this aftermarket CAT due an intermittent P0430. It keep coming back on this new CAT. I want to just get a good look inside with my scope, and likely replace was my thinking. Since it had only been on a few months and 4K miles. I though no big deal, it will zip right off. Wrong!

In looking over now that I have CAT out. It's very apparent this tech used a lot of brute force.

The rear flange of CAT sits at and angle, so that we only need lift up CATs from rear flange once all bolts out and nuts off. This easily frees the whole CAT and we slide the CAT back and the snake out forward.... So SO Easy.

It appears this yahoo SOB &%&^$# at Midas, pulled down on the rear CAT Flange and used brute force to man handle it out.

This is exhaust pipe from muffler that CAT attaches to at rear of CAT.
Notice how down stream pipe is bent down. This must have been from CAT hanging up on pipe and force it down to remove.

I also found the tips of the studs on exhaust manifold have marks that further indicates force used, that he had the CAT jamb in badly and used a lot of force to force it out. Very likely he did some damage to stud threads at that time. Then during assemble just force the nuts onto the studs. When he should have use a thread restore tool first.

Metal to metal swipe across the tips of studs.

He also use the old nuts and bolts. The FSM has a good reason for (list as non reusable) not reusing these nut and bolts.
They are one time use locking nut and they get very damaged form heat and rust.
He cross threaded 2 of the 3 stud on exhaust manifold.

 

[2001LC]

OH but this SOB wasn't satisfied NO. He keep at it!

He went the extra mile. This aftermarket CAT has 2 O2 holes. One must be plugged. He barley got the plug in, in fact it may have been leaking air. Plug has a flat seat/seal washer that they should be run down to. They should also have a crush washer gasket place on them. That can mess up a CAT and or mess with readings I suppose.

But was enough. NOOOOOO

This guy just keep going. What was he 2 years old. DANK, he cross threaded the plug too or use wrong thread pitch IDK.

This is second vehicle in as many weeks I've had to deal with cross threads. I do so much work fixing what these so called pro name brand shop like Midas & Brakes Plus mess up. But this is really simple stuff. It's just plain incompetency on the part of management, lack of competency.

 

[FxFormat]

Don't you love fixing others' hack jobs? lol, i go through this every day at work.

 

[2001LC]

It get old doesn't @FxFormat . I do so love a VC (Virgin Cruiser).
_____________________________________
But did he stop NO I cry NO

I'm looking at the O2 think what is this gray residue on the prob. I'm thinking my CAT must be clogged with gunk. So I scope it, it is clear I can't find and damage or clogs in CAT and it new. WTF why the P0430 DUH

More around other side. I was wiping with finger, seems like a thread sealant IDK.

 

[2001LC]

So is it bad CAT causing the P0430 or fouling from air leak and contaminate on O2 sensors prob. ?

 

[katit]

How did you replace those studs?

I had manifold out so it was much easier. I had nuts welded on broken studs, but NO, it didn't help. I broke them even further trying to unscrew.

Ended up cutting them flush with flange and drilling out. PITA.

 

[bigredmachine]

So is it bad CAT causing the P0430 or fouling from air leak and contaminate on O2 sensors prob. ?

well both aren't helping the situation any, exhaust leaks can and will cause issues with the a/f and o2 sensors reading correctly depending on where the leak is. who knows whatever that goop is, antisleeze, rtv, the installers tears of joy knowing that he did the worst job possible, so I would consider changing the sensor as well. you may be able to clean it up but depending on the mileage it may be better to just replace it

 

[2001LC]

I had manifold out so it was much easier. I had nuts welded on broken studs, but NO, it didn't help. I broke them even further trying to unscrew.

Ended up cutting them flush with flange and drilling out. PITA.

Oh yeah, I remember now seeing that picture of nuts wield on studs.

Sines the heat you created wield didn't break free. My impact and 3/4" breaker did break my stud free. I'm thinking I'll need to drilling out or new exhaust manifold. Bunch of nut bolts and gasket.

well both aren't helping the situation any, exhaust leaks can and will cause issues with the a/f and o2 sensors reading correctly depending on where the leak is. who knows whatever that goop is, antisleeze, rtv, the installers tears of joy knowing that he did the worst job possible, so I would consider changing the sensor as well. you may be able to clean it up but depending on the mileage it may be better to just replace it

Some say you should not even touch and O2 IDK. But differently not slim like this.

You're likely right!

List is growing. $$$$$$$$

 

[katit]

Oh yeah, I remember now seeing that picture of nuts wield on studs.

Sines the heat you created wield didn't break free. My impact and 3/4" breaker did break my stud free. I'm thinking I'll need to drilling out or new exhaust manifold. Bunch of nut bolts and gasket.

They did brake free and I learned to undo it by going forward/backward many times. I did this to one stud. But others I tried to just undo with force and they broke. So, you might be able to carefully work them out. If that makes sense? It makes sense to me now, but I broke 2. I can only say that it doesn't take much force to brake those using regular 3/8 ratchet.

 

[2001LC]

I'll give it a try. But heat was your biggest aid, that I'm sure of. I've only a NAPP gas bottle. I doubt I can get red hot.

Okay, Note to self add torch to the list. $$$$$

The Midas shop that did this is 100 miles away in Glenn Wood Springs, CO.
I need a drive to chill-out. 100 miles would be just about right.