Why are bolts backing out?

[JuGs]

Ok I keep getting random bolts comming loose. First it was the alternator, then it was the casing on the alternator, then exhause mani studs, the the down pipe, the bolts to bolt the turbo to mani and yet the worse of them all my water pump came loose. The water pump ws just last week but its been a issue for the past 3 months. Whats causing this? BS lined up incorrectly?

 

[AG 305]

vibration?? every time i replace something or install something i use lock tite all over like a mo fo

 

[dsmcurse]

hot-cold-hot-cold, exhaust ones will do that, come loose. good idea to double check ALL hot bolts for tightness with every oil change. that way you know every time you service your car you know the manni/turbo bolts arent loose. my alt. bolt once came loose to for "no reason" i think it was all the hottness from turbo situation. as far as water pump bolts, dang man. dont know what to say. i dont have lock-tite or lock washers or nothin. my bolts are always good there. never really heard of that happening befor

 

[Nasty Dream]

I think things that have been screwed down and removed numerous times get looser - tiny particles of metal are shaved off. So Locktite would definitely help.

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And locking nuts (with the little gooey outer edge), wear out and should be replaced. (Or you could try these in the first place).

You can use Locktite for external bolts, and there are different temperature choices. I wouldn't put it anywhere internal or places that will see vacuum, personally. Not sure. Read the label.

 

[phunny]

Is your profile up to date? Do you have stock mounts or prothane? When you install the bolts make sure to use a torque wrench and locktite appropiate for that application .

 

[obsidian]

Vibrations causes things to back out and every engine has vibrations. I honestly hate my balance shaft eliminator to death. BUT my balance shaft is not there to seize and blow my engine up so it's kinda a lose/win for me. Lose for the stupid vibes but win for the reliability.

Anyway, for bolts, try some lock washers.

They look like this.

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That will help with the loctite (I'm not a fan myself) but will help keep the bolts from backing out.

On nuts, like stated above, try some "nyloc" nuts. That "gooey" stuff is actually a strip of nylon which is a piece of platic. Helps lock the nut onto the bolt and keeps them in place. However, nylocs wear out after 2-3 uses (off and on) so you'll have to replace them. The plastic also melts in hi temps so they're useless on a hot exhaust system.

 

[JuGs]

I still have stock mounts. I guess im just having that bad of luck . This cars been a nitemare for me.

 

[Nasty Dream]

There should be nothing wrong with stock mounts if they are not damaged. I mean you just have bolt-ons.

I think all the information you need is in this thread.

You can take one of your bolts/nuts to a place like Lowes to find out the diameter and spacing of the threads. I'm sure one of the guys in the hardware section can explain that to you.

Then measure the length of the bolt.

You can look on the end of a bolt to find the 'strength'. There should be a number on metric bolts indicating the 'strength'.

http://en.wikipedia.org/wiki/Screw_thread
http://en.wikipedia.org/wiki/ISO_metric_screw_thread

Then find suitable replacements. If it's for something specific like an engine, I'm sure you don't have to measure, just search for head bolts/hardware, etc. But generally, you can just replace worn nuts and bolts with OEM. This is especially a good idea if they are rusty!

 

[romeen]

I've been using Nord-Lock washers on critical areas and they work awesome. I have solid front/rear motor mounts so the car vibrates a decent amount.

Maximum security for bolted joints -Home - Nord-Lock