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Help needed with #3 body mount bolts

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Old Apr 17, 2020 | 01:57 PM
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Default Help needed with #3 body mount bolts

I have all my body mount bolts out except for both #3s. I did have to grind out both #4s.

These are stuck so hard I already split a socket. Is there anyway to get PB Blaster on the threads of the bolt? I can't see much thru the little access door.. Even getting a grinder in there would be a PITA.
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Old Apr 17, 2020 | 05:46 PM
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Apparently there's a cage welded to the inside of the frame with a nut in it. If the nut spins in the cage, you're screwed. They say once you get the body off you can get in there and cut out the cage and Weld in the new cage with another nut inside.
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Old Apr 17, 2020 | 05:57 PM
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. At the 2 minute mark exactly there's a close up of the number 3 body mount rusty as hell with the body removed. It looks like you could get a spray thing of PB or WD40 and go up in and spray sideways above the frame it looks like the cage with the nut in it is not inside the frame but on top of the frame. The opening shot of the video is the number 3 mount bolt and then 5 seconds later it looks like with the head drilled off. 4 min 50 mark shows right #3. Then a good shot looking down from above at 8 min 50 shows you want to stick straw outboard right in front of the kickups slightly pointing to the rear. Like between 3 and 4 o clock. Or 8-9 on other side. WD40 easy reach. https://shop.advanceautoparts.com/p/...hoCBjIQAvD_BwE

Last edited by derekderek; Apr 17, 2020 at 06:34 PM.
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Old Apr 17, 2020 | 06:43 PM
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Thanks Derek.It helps to see what the little frame mount u-bracket looks like.
I tried from 2 directions from the tire side and it did not seem to do much. Now I see why. I don't think I hit the threads at all.
Now I'm going to go try from the inside of the car, seat side. It looks like I might be able to reach the threads from there.
I'll try it this evening and let you know how it goes.




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Old Apr 17, 2020 | 07:00 PM
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You might also try up over the frame from outboard, between side pipes and frame. I think the flexi straw wd will be the best option.
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Old Apr 17, 2020 | 08:09 PM
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From the seat side did not work. Body was in the way. I think I'll have to try this angle, but it would help if I had a little small piece of copper tubing or something that I could bend into at least 45 degree angle. I tried from here with the plastic straw and don't think I got into the center where the bolt is. The u-shape mount appears to only be open on the right and the left.
From where the sidepipes mount, I can just barely see the edge of the mount, but it is a solid side, can't spray the bolt.


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Old Apr 17, 2020 | 11:02 PM
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That idea didn't work either.
I finally found a can of PB blaster that I could bend the nozzle on. That worked.That was Dereks idea. Thanks Derek! Iwent straight up by the sidepipe area and 90 degree to the rusty bolt. I hope Lowes didn't mind me testing it before I bought it!

So Hoo-Ray I backed one out that way. The other one the bolt head was too damaged from the socket that broke, so even a new hardened impact socket slipped off.
So this little pencil sized micro-grinder became my favorite new tool. It fit into that little access door and ground the head off in 30 min.

I don't even think the rust is very bad back here at all. I am really pleased at that.



Well the #3 body mount might not be rusted, but that #3 bolt was still obnoxious. Any idea why? I see one absolutely clean spot on the bolt. How can that be? Does anyone think it was just seized onto the nut?

Last edited by leigh1322; Apr 17, 2020 at 11:08 PM.
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Old Apr 18, 2020 | 03:27 AM
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this was my 69 , see the two layers of steel in the actual mount hole , the bottom is the sill panel , I can only see one in your pic. Your fun is just beginning.
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Old Apr 18, 2020 | 11:39 AM
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Thanks Bazaa! I'll be cleaning that and comparing it to yours.
OK Sat noon update.
I am really pleased with the condition and lack of rust in the body mounts.

Mount no. 1 pass under hood


#2 pass inside cabin


Masking tape for shims removed from no. 2 mount


#3 pass by trailing arm


#4 pass behind tire the powdery stuff is the corroded aluminum disc. it brushes off easily.


All of which are drastically better than my windshield frame, which has five holes like this. All 4 corners and the VIN tag joint. I'll still have plenty of "fun" LOL.



Last edited by leigh1322; Apr 18, 2020 at 04:09 PM.
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Old Apr 18, 2020 | 05:31 PM
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Originally Posted by leigh1322
Thanks Bazaa! I'll be cleaning that and comparing it to yours.
OK Sat noon update.
I am really pleased with the condition and lack of rust in the body mounts.



#2 pass inside cabin



I'll still have plenty of "fun" LOL.

Hmm , don't count any chickens yet Leigh , mine looked like yours , see how there,s rust expanding at the top of your left side tab , mine looked good inside as well but was rotten outside .like this,


I hope yours isn't like this .

same side , out the front ,


totally rotten in there , put a screw driver through it easily

Last edited by bazza77; Apr 18, 2020 at 05:33 PM.
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Old Apr 18, 2020 | 07:14 PM
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Thanks guys for the preview... That's exactly where I'm headed. Oh boy!
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Old Apr 18, 2020 | 07:22 PM
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Yikes!!!!
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Old Apr 18, 2020 | 09:26 PM
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Originally Posted by leigh1322
Yikes!!!!
Thanks for the posts and educational info!

Keep the learnings coming as I am sure me and others will have to also deal with this sooner than we think.

Last edited by 20mercury; Apr 18, 2020 at 09:32 PM.
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Old Apr 19, 2020 | 08:41 AM
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Got torches? Once body is off heat the nut inside the cage and bolt should come out with vice grips. Might wanna grind flats on bolt shaft for better grip.
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Old Apr 19, 2020 | 09:25 AM
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Great idea.
I have 4 bolt "studs" I'll have to deal with now. Is a MAPP torch hot enough?
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Old Apr 19, 2020 | 09:29 PM
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No.oxy acetelyne. Gotta make nut glow orange.
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Old Apr 19, 2020 | 11:11 PM
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Once you can get at them ., your probably going to be better off replacing the whole mount with a nice new one . Usually the cages are rusty thin and damaged from forcing the original bolt out.
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Old Apr 19, 2020 | 11:33 PM
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Originally Posted by bazza77
Once you can get at them ., your probably going to be better off replacing the whole mount with a nice new one . Usually the cages are rusty thin and damaged from forcing the original bolt out.
Yeah I don't have a torch, so I might just cut them off anyway.
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Old Apr 20, 2020 | 06:19 AM
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You are buying a set of torches. Trust me. There is stuff you can weld with gas that can not be welded with electricity. Like windshield frames that have rusted. And many places fighting a stuck bolt you are gonna wish you had heat. When is body coming off?

Last edited by derekderek; Apr 20, 2020 at 06:28 AM.
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Old Apr 20, 2020 | 10:17 AM
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Originally Posted by derekderek
You are buying a set of torches. Trust me. There is stuff you can weld with gas that can not be welded with electricity. Like windshield frames that have rusted. And many places fighting a stuck bolt you are gonna wish you had heat. When is body coming off?
Yeah you could be right. I am acquiring many more tools than I imagined. All that's left is front & rear bumpers and seat belt/parking brake connections. Got to build a body dolly. Then lift-off!
Say a week? Depends on how much school work I have to do.
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