Loctite is a pain!

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Had to replace a motor mount on the Fusion today. Of the fasteners that hold the mount to the body of the car, 2 of them are bolts with blue Loctite applied from the factory. I've read stories that these bolts in particular are tough to remove, and boy were those stories right! Took a lot just to get them to budge, with a loud "crack!" when they finally did. They didn't get easy to turn until about halfway out; until then I still had to wrench real hard to get them to turn.

When going to install the new mount, I applied some new Loctite blue to the fasteners, and started them all by hand. These two bolts took a LOT of fighting to get seated, from about the point where they were halfway threaded. It was almost like they were cross-threaded, but I assure you they weren't; I started the first few turns by hand. They were so hard going down that I was sure I had seated them, but nope, still a ways to go. Finally the one seated, and I knew this only because I couldn't move the mount anymore. The second bolt I also assume seated fine, but took forever. I really have no idea now much the final torque value was, since I needed an 18" breaker to get them to go back in.

These were big bolts, and I assume Loctite makes the assembly and removal process more difficult, but is this normal? Maybe the fact that it was mixed with a little rust didn't help.
 
Originally Posted By: mechjames
I bet that the OEM hardware uses crush nuts in addition to the loctite. There is no way to spin those crush nuts on and off by hand.


Hardware is exactly the same. The mount is just stamped sheet metal and the bolts pass through it.
 
Originally Posted By: Merkava_4
You're supposed to remove the old Loctite before applying new Loctite.


Ah, that could be it
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oh well, they're in there now. Although there wasn't really any Loctite buildup on the bolts when they came out; just a blue stain almost.
 
Although there were 2 other bolts that I also just added more Loctite to during reassembly, and I didn't have this issue with them. One of these bolts was quite large. I'm thinking rust played a role with the other 2 being very resistant to coming out and going back in.
 
When I do stuff like that I chase the hole with a tap and at least wire wheel the bolt. Then add new Loctite.
 
Sometimes even a wire wheel won't take the stuff off; when that happens, I clamp a sewing needle into a pair of vise-grips and pick the stuff out.
 
Yeah I would have done what NYEngineer said, chased the hole and wire wheeled the bolt. I feel like it was probably the rust that did it more than not.

There have been times where I had to remove fasteners that didn't have any thread locker and it seems the torque needed to spin it (not break it free) is a function of how rusted the threads are.

Once I get the bolt out I usually chase the hole and wire wheel the bolt and then it's like night and day when I'm putting it back in, only needing to spin the bolt with my fingers now. Also a little bit of oil like penetrating oil makes a big difference too (but I think most torque specs are dry specs so watch out).

Those times I really had to torque on it the whole way to get it out, the fasteners made screaming noises as I turned them, so loud you could have heard it half way down the street. When it finally did come out the friction must have been severe because the fastener that started out cold was then searing hot, so hot I couldn't hold it without burning my hand.
 
If the original dab of the thread locker was still there, I wouldn't apply more thread locker to the fastener, unless I cleaned off the old stuff off. I hope you don't have to remove the mount again, it will be even more difficult the next time around.

Up here in Canada, rust is an excellent thread locker. I've had plenty of fasteners that broke free no problem, giving me a false sense of hope, only to shear off during the extraction. Fun times
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I've twisted the head off a bolt on many a car that lived within 3 miles of the coast here. Salt air is right up there with salted roads for eating up a car. The salt on the roads is worse but I'm 13 miles from the coast and a chromed tool will have rust spots in a week if left in the garage. It's quite impressive
 
Quote:
and a chromed tool will have rust spots in a week if left in the garage. It's quite impressive

Wow, can imagine how awful that would be.
 
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